JP6468387B2 - Information recording medium - Google Patents

Description

  The present invention relates to a technique for writing and storing information on a durable information recording medium, and in particular, a technique for recording information as a fine physical structure pattern by performing beam exposure and patterning processing on a substrate. About.

  Paper has long been used as a medium for recording various information, and even today, a lot of information is recorded on paper. On the other hand, with the development of industry, films for recording image information and record boards for recording sound information have come to be used. In recent years, with the spread of computers, a medium for recording digital data As a result, magnetic recording media, optical recording media, semiconductor recording media, and the like have been used.

  The above-described information recording medium has durability to the extent that it does not hinder use depending on the application. For example, an information recording medium such as a printed matter of paper, a film, or a record board can be said to have sufficient durability on a time scale of several years. However, when viewed on a time scale such as several decades, deterioration due to aging is unavoidable, and the recorded information may be lost. Moreover, it may be damaged not only by aging but also by the action of water and heat.

  Also, magnetic recording media for computers, optical recording media, semiconductor recording media, etc. have durability that does not hinder the use of general electronic equipment, but in the first place it is a time scale of several decades. Since it is not designed in consideration of durability, it is not suitable for permanent information storage.

  On the other hand, in Patent Document 1 below, as a method of recording information on a durable medium such as quartz glass while increasing the recording capacity, a three-dimensional difference in light transmittance is measured on a minute cell in a cylindrical medium. In particular, a method is disclosed in which data is recorded and information is read using a computer tomography technique while rotating the medium. Further, in Patent Document 2, in order to achieve the same object, the difference in transmittance is measured by irradiating electromagnetic waves while changing the irradiation angle to a cylindrical recording medium, and the computer tomography technique is also used. A method of reading information using it is disclosed.

  There are two types of plate-shaped information recording media: front / back, top / bottom, and left / right. When reading recorded information, the reading process is performed after correctly recognizing the front / back, top / bottom, left / right, etc. of the medium. There is a need to do. Therefore, a method has been proposed in which an identification mark indicating a direction for performing a correct reading process is attached on a medium. For example, in Patent Document 3 below, by providing an identification mark made of a concavo-convex structure in the lower right corner on the front side of a card-shaped information recording medium, even the visually impaired can recognize the orientation of the medium by touch, A technique for enabling a card-shaped information recording medium to be inserted into an information reading device in the correct direction is disclosed.

Japanese Patent No. 4991487 Japanese Patent No. 5286246 JP-A-9-269987

  As described above, information recording media that are generally used at present are designed in consideration of durability of several years to several tens of years, and therefore have a long time scale of hundreds to thousands of years. It is inappropriate to leave information for future generations. For example, a physically or chemically weak information recording medium such as paper, film, or record board cannot be expected to have durability for a long period of several hundred years to thousands of years. Of course, computer information recording media such as magnetic recording media, optical recording media, and semiconductor recording media are also unsuitable for such applications.

  In human history, stone monuments exist as information recording media that have passed time scales of hundreds to thousands of years. However, it is very difficult to record information on a stone board with a high degree of integration. A stone board is not suitable as a medium for recording large amounts of information such as digital data.

  On the other hand, if a method of recording information three-dimensionally using a cylindrical quartz glass as a medium as in the techniques disclosed in the above-mentioned Patent Documents 1 and 2, the durability is considerably long-term. Thus, an information recording method capable of achieving high integration while maintaining the performance can be realized. However, at the time of reading, it is necessary to extract information from cells that are three-dimensionally distributed in the medium. Therefore, it is necessary to perform a Fourier transform process using a computer tomography technique. In other words, even after a long time scale of hundreds to thousands of years, information cannot be read out unless the same computer tomography technology as that used for recording is inherited.

  Therefore, the inventor of the present application can record information with a high degree of integration while maintaining long-term durability in Japanese Patent Application No. 2014-059542 (hereinafter referred to as the prior application), and in a universal manner. An information storage method and apparatus capable of reading information were proposed, and a method and apparatus for reading original information from a medium in which information was stored by such a method was proposed. Hereinafter, the content of the proposal in this prior application is referred to as the prior application invention.

  In the prior application invention, the digital data to be stored is expressed as a graphic pattern and transferred onto the substrate by beam exposure using an electron beam or laser light. Then, by performing a patterning process on the substrate, data is recorded as a fine physical structure pattern. Therefore, information can be recorded with a high degree of integration while maintaining long-term durability. Moreover, since the graphic pattern itself transferred onto the substrate is a two-dimensional pattern, information can be read out by a universal method.

  However, even when beam exposure and patterning are performed using the same graphic pattern, the physical structure actually formed on the substrate differs depending on the method of beam exposure and patterning employed. For example, when the bit “0” and the bit “1” are separately recorded as the concavo-convex structure formed on the substrate, the convex portion becomes the bit “1” depending on the employed beam exposure and patterning method, The recess becomes a bit “1”.

  Specifically, at the time of beam exposure, the result of recording on the medium differs depending on whether an area indicating bit “0” is exposed or an area indicating bit “1” is exposed. Similarly, the result of recording on the medium varies depending on the patterning process conditions such as whether a positive resist or a negative resist is used as the resist layer formed on the substrate. Therefore, only the information of the data bits recorded on the information recording medium should be read by interpreting the convex portion as bit “1” or reading the concave portion as bit “1”. I cannot recognize it.

Therefore, the present invention can record information indicating a data bit interpretation method when recording information as a fine physical structure pattern by performing beam exposure and patterning processing on the substrate. An object is to provide an information recording medium .

(1) According to a first aspect of the present invention, there is provided an information storage device for writing and storing digital data in an information recording medium.
A data input unit for inputting digital data to be stored;
A main information pattern generation unit that generates a main information pattern indicating information of individual data bits constituting the digital data;
A sub information pattern generation unit that generates a sub information pattern indicating a method of interpreting the data bits indicated by the main information pattern;
A drawing data generation unit for generating drawing data for drawing the main information pattern and the sub information pattern;
A beam exposure apparatus that performs beam exposure using an electron beam or laser light on a substrate serving as an information recording medium based on the drawing data;
A patterning apparatus that generates an information recording medium on which a physical structure pattern corresponding to drawing data is formed by performing a patterning process on the exposed substrate;
Provided,
The main information pattern is composed of a first attribute main area and a second attribute main area, and a predetermined point corresponding to each data bit exists in the first attribute main area, or a second attribute main area. Depending on whether it exists in the area, the binary information of each data bit is expressed as a pattern,
The sub-information pattern includes a first identification mark having one or a plurality of closed regions for presenting first information composed of letters, numbers, symbols, figures, or a part thereof, or a combination thereof. And a second identification mark having one or a plurality of closed regions for presenting second information composed of letters, numbers, symbols, figures, or a part thereof, or a combination thereof. And
In the closed region constituting the first identification mark, a strip-shaped first attribute sub-region and a strip-shaped second attribute sub-region extending in a direction parallel to the predetermined placement axis Z are orthogonal to the placement axis Z. The band-shaped first attribute sub-area and the band-shaped second attribute sub-area extending in the direction parallel to the arrangement axis Z are disposed in the closed area that is alternately arranged in the direction and constitutes the second identification mark. For the closed region that is alternately arranged in the direction orthogonal to the arrangement axis Z and that forms the first identification mark, the width of the first attribute subregion is greater than the width of the second attribute subregion. The closed region that is set to be wide and constitutes the second identification mark is set so that the width of the second attribute sub-region is wider than the width of the first attribute sub-region,
The drawing data generation unit performs exposure for performing exposure on the first attribute main area and the first attribute sub area and for performing exposure on the second attribute main area and the second attribute sub area. Data or drawing data for performing exposure on the second attribute main area and the second attribute sub area and not exposing the first attribute main area and the first attribute sub area. The widths of the first attribute sub-region and the second attribute sub-region are set to dimensions that can form a diffraction grating for visible light.

(2) According to a second aspect of the present invention, in the information storage device according to the first aspect described above,
The sub information pattern generation unit generates a sub information pattern in which the first identification mark and the second identification mark formed on the information recording medium have a size that can be visually observed.

(3) According to a third aspect of the present invention, in the information storage device according to the first or second aspect described above,
The sub-information pattern generation unit sets the width of the first attribute sub-region so that the width of the first attribute sub-region is five times or more of the width of the second attribute sub-region with respect to the closed region constituting the first identification mark. The closed region constituting the mark is set so that the width of the second attribute subregion is at least five times the width of the first attribute subregion.

(4) According to a fourth aspect of the present invention, in the information storage device according to the first to third aspects described above,
The sub information pattern generation unit sets the width of the first attribute sub-region in the closed region constituting the first identification mark equal to the width of the second attribute sub-region in the closed region constituting the second identification mark. The width of the second attribute sub-region in the closed region constituting the first identification mark is set equal to the width of the first attribute sub-region in the closed region constituting the second identification mark. It is.

(5) According to a fifth aspect of the present invention, in the information storage device according to the first to fourth aspects described above,
The sub information pattern generation unit generates a sub information pattern in which the first identification mark and the second identification mark are arranged adjacent to each other.

(6) According to a sixth aspect of the present invention, in the information storage device according to the first to fourth aspects described above,
The sub information pattern generation unit generates a sub information pattern in which the closed region constituting the first identification mark and the closed region constituting the second identification mark are in contact with each other.

(7) According to a seventh aspect of the present invention, in the information storage device according to the first to fourth aspects described above,
The sub information pattern generation unit generates a sub information pattern in which the second identification mark is embedded in the first identification mark or a sub information pattern in which the first identification mark is embedded in the second identification mark. It is what you do.

(8) According to an eighth aspect of the present invention, in the information storage device according to the first to fourth aspects described above,
In addition to the first identification mark and the second identification mark, the sub information pattern generation unit further generates a sub information pattern having an auxiliary common identification mark,
This auxiliary common identification mark is an identification mark having one or a plurality of closed regions for presenting auxiliary common information consisting of letters, numbers, symbols, figures, or parts thereof, or combinations thereof,
In the closed region constituting the auxiliary common identification mark, the strip-shaped first attribute sub-region and the strip-shaped second attribute sub-region extending in the direction parallel to the arrangement axis Z are alternately arranged in the direction orthogonal to the arrangement axis Z. And the difference between the width of the first attribute sub-area and the width of the second attribute sub-area in the auxiliary common identification mark is the first attribute sub-area in the first identification mark and the second identification mark. The difference between the width of the area and the width of the second attribute sub-area is set to be smaller.

(9) According to a ninth aspect of the present invention, in the information storage device according to the eighth aspect described above,
The width of the first attribute sub-region and the width of the second attribute sub-region in the auxiliary common identification mark are set to be equal.

(10) According to a tenth aspect of the present invention, in the information storage device according to the eighth or ninth aspect described above,
The combination of the first identification mark and the auxiliary common identification mark constitutes a mark indicating the first interpretation method of the data bits indicated by the main information pattern, and the second identification mark and the auxiliary common identification mark A mark indicating the second interpretation method of the data bits indicated by the main information pattern is constituted by the combination.

(11) An eleventh aspect of the present invention is the information storage device according to the tenth aspect described above,
Three rectangles, a left rectangle, a center rectangle, and a right rectangle, are arranged adjacent to each other in the horizontal direction so that they are on the left side, the center, and the right side, respectively. And place
By forming the first identification mark with the central rectangle, the second identification mark with the left and right rectangles, and the auxiliary common identification mark with the lower rectangle, the first mark indicating the character “convex” is formed. A chapter and a second mark indicating the character “concave” are configured.

(12) In a twelfth aspect of the present invention, in the information storage device according to the first to eleventh aspects described above,
The beam exposure apparatus has a function of performing beam exposure on the surface of the resist layer for a substrate having a layer to be molded and a resist layer covering the layer to be molded,
A patterning device includes a development processing unit for performing processing in which a substrate is impregnated with a developer having a property of dissolving an exposed portion or a non-exposed portion of the resist layer, and a part thereof is a remaining portion, and a remaining portion of the resist layer. And an etching processing unit that performs etching on the layer to be molded as a mask.

(13) According to a thirteenth aspect of the present invention, in the information storage device according to the twelfth aspect described above,
The main information pattern generation unit converts any one of the individual bits “1” and individual bits “0” into individual bit figures including closed areas, and converts the area inside the bit figure to the first. Generate a main information pattern with the attribute main area and the external area as the second attribute main area,
Drawing for causing the drawing data generation unit to perform exposure on the first attribute main area and the first attribute sub area and not to perform exposure on the second attribute main area and the second attribute sub area The data is generated.

(14) According to a fourteenth aspect of the present invention, in the information storage device according to the first to thirteenth aspects described above,
The patterning apparatus forms a physical structure having a concavo-convex structure including a concave portion indicating one of the first attribute region and the second attribute region and a convex portion indicating the other.

(15) According to a fifteenth aspect of the present invention, in the information storage device according to the fourteenth aspect described above,
The patterning apparatus forms a physical structure having an additional layer made of a light-reflective material on the surface of the convex portion.

(16) According to a sixteenth aspect of the present invention, in the information storage device according to the fourteenth aspect described above,
The patterning device forms a concavo-convex structure on the upper surface by patterning the substrate made of a light-transmitting material, and forms a physical structure having an additional layer made of a light-shielding material on the lower surface of the substrate. It is a thing.

(17) According to a seventeenth aspect of the present invention, in the information storage device according to the fourteenth aspect described above,
The patterning device forms a concavo-convex structure by patterning a substrate made of a light-transmitting material, and forms a physical structure having an additional layer made of a light-shielding material on the surface of the convex portion. It is a thing.

(18) According to an eighteenth aspect of the present invention, in the information storage device according to the first to thirteenth aspects described above,
The patterning apparatus forms a physical structure having a network structure including a through hole indicating one of the first attribute region and the second attribute region and a non-hole portion indicating the other. .

(19) According to a nineteenth aspect of the present invention, in the information storage device according to the eighteenth aspect described above,
The patterning apparatus forms a physical structure having an additional layer made of a light reflecting material on one surface of the non-hole portion.

(20) According to a twentieth aspect of the present invention, in the information storage device according to the eighteenth aspect described above,
The patterning apparatus forms a network structure by patterning a substrate made of a light-transmitting material, and forms a physical structure having an additional layer made of a light-shielding material on one surface of the non-hole portion. It is a thing.

(21) According to a twenty-first aspect of the present invention, in the information storage device according to the first to eleventh aspects described above,
A data input unit, a main information pattern generation unit, a sub information pattern generation unit, and a drawing data generation unit are configured by incorporating a program into a computer.

  (22) According to a twenty-second aspect of the present invention, there is provided a computer as a data input unit, a main information pattern generation unit, a sub information pattern generation unit, and a drawing data generation unit in the information storage device according to the first to eleventh aspects. A program to make it function is prepared.

(23) According to a twenty-third aspect of the present invention, in an information storage method for writing and storing digital data in an information recording medium,
A data input stage in which a computer inputs digital data to be stored;
A main information pattern generation stage in which a computer generates a main information pattern indicating information of individual data bits constituting digital data;
A sub-information pattern generation stage, wherein the computer generates a sub-information pattern indicating how to interpret the data bits indicated by the main information pattern;
A drawing data generation stage in which a computer generates drawing data for drawing the main information pattern and the sub information pattern;
A beam exposure step of performing beam exposure using an electron beam or laser light on a substrate serving as an information recording medium based on the drawing data;
A patterning step for generating an information recording medium on which a physical structure pattern corresponding to drawing data is formed by performing a patterning process on the exposed substrate;
And do
The main information pattern is composed of a first attribute main area and a second attribute main area, and a predetermined point corresponding to each data bit exists in the first attribute main area, or a second attribute main area. Depending on whether it exists in the area or not, the binary information of each data bit should be expressed as a pattern,
The sub-information pattern includes a first identification mark having one or a plurality of closed regions for presenting first information composed of letters, numbers, symbols, figures, or a part thereof, or a combination thereof. And a second identification mark having one or a plurality of closed regions for presenting second information composed of letters, numbers, symbols, figures, or parts thereof, or combinations thereof. And
In the closed region constituting the first identification mark, a strip-shaped first attribute sub-region and a strip-shaped second attribute sub-region extending in a direction parallel to the predetermined placement axis Z are orthogonal to the placement axis Z. The band-shaped first attribute sub-area and the band-shaped second attribute sub-area extending in the direction parallel to the arrangement axis Z are disposed in the closed area that is alternately arranged in the direction and constitutes the second identification mark. For the closed region that is alternately arranged in the direction orthogonal to the arrangement axis Z and that forms the first identification mark, the width of the first attribute subregion is greater than the width of the second attribute subregion. For the closed region that is set to be wide and constitutes the second identification mark, the width of the second attribute subregion is set to be wider than the width of the first attribute subregion,
In the drawing data generation stage, drawing is performed so that the first attribute main area and the first attribute sub area are exposed, and the second attribute main area and the second attribute sub area are not exposed. Data or drawing data for performing exposure on the second attribute main area and the second attribute sub area and not exposing the first attribute main area and the first attribute sub area. The size is set so that the first attribute sub-area and the second attribute sub-area can be configured to form a diffraction grating for visible light.

  According to the present invention, information of individual data bits constituting digital data to be stored is recorded as a main information pattern on the medium, and further shows a method for interpreting the data bits indicated by the main information pattern. Information is recorded as a sub information pattern on the same medium. Here, each information pattern is composed of a first attribute area and a second attribute area. For example, information is recorded on the substrate so that one attribute area is a convex portion and the other attribute area is a concave portion. Done. The sub-information pattern includes a pair of identification marks, and a diffraction grating in which band-shaped first attribute areas and band-shaped second attribute areas are alternately arranged is formed in each identification mark. .

  In addition, the magnitude relationship between the width of the band-shaped first attribute area and the width of the band-shaped second attribute area formed in each identification mark is reversed with respect to the pair of identification marks. For this reason, regardless of the beam exposure and patterning methods employed during information recording, the correct interpretation of the data bits recorded as the main information pattern can be recognized by comparing the brightness of the pair of identification marks. it can.

  Thus, according to the present invention, when information is recorded as a fine physical structure pattern by performing beam exposure and patterning processing on the substrate, information indicating how to interpret the data bits is also recorded. It becomes possible to do.

It is a block diagram which shows the basic composition of the information storage apparatus which can utilize this invention. It is a schematic diagram which shows an example of the specific information storage process by the information storage apparatus shown in FIG. FIG. 3 is an enlarged view of a unit recording graphic pattern R (U1) shown in FIG. 2. FIG. 2 is a side sectional view showing a specific process (a process using a positive resist as the resist layer 20) of an exposure process by the beam exposure apparatus 200 and a patterning process by the patterning apparatus 300 shown in FIG. The illustration of the back structure is omitted). It is a sectional side view which shows the variation of the information recording medium with which information was written by the information storage apparatus shown in FIG. 1 (only a cut surface is shown and illustration of a back structure is abbreviate | omitted). It is a block diagram which shows the basic composition of the information reading device for reading information from the information recording medium produced by the information storage device shown in FIG. It is a top view which shows the variation of the alignment mark used with the information storage apparatus shown in FIG. It is a top view which shows the variation of the arrangement | positioning form of the alignment mark used with the information storage apparatus shown in FIG. It is a top view which shows another variation of the alignment mark used with the information storage apparatus shown in FIG. It is a top view which shows another variation of the arrangement | positioning form of the alignment mark used with the information storage apparatus shown in FIG. It is a flowchart which shows the basic process sequence of the information storage process performed with the information storage apparatus shown in FIG. It is a flowchart which shows the basic process sequence of the information reading process performed with the information reading apparatus shown in FIG. It is side sectional drawing which shows the general replication method of the information recording medium in which the uneven structure was formed in the surface. It is a sectional side view which shows the state by which the duplicate was created by the replication method shown in FIG. FIG. 5 is a plan view showing the relationship between an original M1 and its duplicate M2 when a method of recording a large “F” as an identification mark is used (hatching is for indicating an area). FIG. 5 is a side sectional view showing another specific process (a process using a negative resist as the resist layer 20) different from the exposure step and the patterning step shown in FIG. 4 (only the cut surface is shown and the back structure is shown). Is omitted). FIG. 17 is a plan view showing a relationship between an original plate M3 created by the process shown in FIG. 16 and its duplicate M4 (hatching is for showing regions). It is a block diagram which shows the basic composition of the information storage apparatus which concerns on fundamental embodiment of this invention. FIG. 19 is a plan view showing an information recording medium M5 created by executing the process shown in FIG. 4 by the information storage device shown in FIG. 18 (hatching is for indicating an area). It is a top view which shows the information recording medium M6 produced by performing the process shown in FIG. 16 with the information storage apparatus shown in FIG. 18 (hatching is for showing an area | region). FIG. 19 is a plan view showing an example of a drawing pattern P (E) created by the information storage device shown in FIG. 18. It is a figure which shows the uneven structure of the medium M5 ("black concave medium" shown in FIG. 19) produced by performing the process shown in FIG. 4 based on the drawing pattern P (E) shown in FIG. It is a figure which shows the uneven structure of the medium M6 ("black convex medium" shown in FIG. 20) produced by performing the process shown in FIG. 16 based on the drawing pattern P (E) shown in FIG. It is an expanded sectional side view of each uneven structure shown in the lower stage of FIG. It is an expanded side sectional view of each uneven structure shown in the lower part of FIG. It is a top view which shows the basic example of a structure and arrangement | positioning aspect of the identification mark used for this invention. It is a top view which shows the modification of the structure and arrangement | positioning aspect of the identification mark used for this invention. It is a top view which shows another modification of a structure and arrangement | positioning aspect of the identification mark used for this invention. FIG. 29 is a plan view of a drawing pattern P (E) having an identification mark according to a modification shown in FIG. It is a top view which shows the modification which uses an auxiliary common identification mark in addition to the 1st identification mark and the 2nd identification mark. It is a top view which shows the observation mode of each identification mark in the modification shown in FIG. 30 (hatching is for showing an area | region). FIG. 19 is a side sectional view showing a first variation of the information recording medium on which information is written by the information storage device shown in FIG. 18 (only the cut surface is shown and the back structure is omitted). FIG. 19 is a side sectional view showing a second variation of the information recording medium on which information is written by the information storage device shown in FIG. 18 (only the cut surface is shown and the illustration of the back structure is omitted). FIG. 19 is a side sectional view showing a third variation of the information recording medium on which information is written by the information storage device shown in FIG. 18 (only the cut surface is shown, and the illustration of the back structure is omitted). FIG. 19 is a side sectional view showing a fourth variation of the information recording medium on which information is written by the information storage device shown in FIG. 18 (only the cut surface is shown and the illustration of the back structure is omitted). FIG. 19 is a side sectional view showing a fifth variation of the information recording medium on which information is written by the information storage device shown in FIG. 18 (only the cut surface is shown, and the illustration of the back structure is omitted). It is a sectional side view which shows the 6th variation of the information recording medium with which information was written by the information storage apparatus shown in FIG. 18 (only a cut surface is shown and illustration of a back structure is abbreviate | omitted). It is a sectional side view which shows the 7th variation of the information recording medium with which information was written by the information storage apparatus shown in FIG. 18 (only a cut surface is shown and illustration of a back structure is abbreviate | omitted). It is a sectional side view which shows the 8th variation of the information recording medium with which information was written by the information storage apparatus shown in FIG. 18 (only a cut surface is shown and illustration of a back structure is abbreviate | omitted). It is a flowchart which shows the basic process sequence of the information storage process performed with the information storage apparatus shown in FIG.

  Hereinafter, the present invention will be described based on the illustrated embodiments. As described above, the present invention is premised on a technique for recording information as a fine physical structure pattern by performing beam exposure and patterning processing on a substrate. The invention is described in Japanese Patent Application No. 2014-059542 as the claimed invention. Since the contents of the invention of the prior application have not been disclosed at the time of filing the present application, the invention of the prior application will be described here in §1 to §5 for convenience of explanation. The contents of the following §1 to §5 and the contents of FIGS. 1 to 12 are the same as the contents of §1 to §5 of “Mode for Carrying Out the Invention” and FIGS. Substantially the same.

<<< §1. Basic embodiment of information storage device according to invention of prior application >>>
FIG. 1 is a block diagram showing the configuration of a basic embodiment of an information storage device according to the invention of the prior application. The information storage device according to this embodiment is a device that performs the function of writing and storing digital data on an information recording medium, and includes a storage processing computer 100, a beam exposure device 200, and a patterning device 300, as shown. .

  Here, the storage processing computer 100 executes a process of creating the drawing data E based on the digital data D to be stored. The beam exposure apparatus 200 is an apparatus that performs beam exposure using an electron beam or laser light on a substrate S serving as an information recording medium based on the drawing data E. A drawing pattern is formed. The patterning apparatus 300 forms a physical structure pattern according to the drawing data E by performing a patterning process on the exposed substrate S, and creates an information recording medium M. Eventually, information corresponding to the digital data D is recorded on the information recording medium M as a physical structure pattern.

  As shown in the figure, the storage processing computer 100 includes a data input unit 110, a unit data generation unit 120, a unit bit matrix generation unit 130, a unit bit graphic pattern generation unit 140, a unit recording graphic pattern generation unit 150, and a drawing data generation unit. 160. Hereinafter, functions of these units will be described in order. However, each of these units is actually a component realized by incorporating a dedicated program into the computer, and the storage processing computer 100 can be configured by installing a dedicated program on a general-purpose computer. it can.

  First, the data input unit 110 is a component having a function of inputting digital data D to be stored, and also has a function of temporarily storing the input digital data D. The digital data D to be stored may be in any form such as document data, image data, and audio data.

  The unit data generation unit 120 is a component that generates a plurality of unit data by dividing the digital data D input by the data input unit 110 into predetermined bit length units. Here, for convenience of explanation, as shown in the upper part of FIG. 2, the following explanation will be given with an example in which four sets of unit data are generated by dividing the digital data D in units of the bit length u. And the i-th unit data is indicated by a symbol Ui (i = 1 to 4 in this example). The terms having the phrase “unit” used in the following description indicate that they are created for “one unit data”.

  The bit lengths of the individual unit data Ui are not necessarily equal, and a plurality of unit data having different bit lengths may be generated. However, for practical use, it is preferable that a bit recording area Ab described later is an area having the same shape and the same area. For this purpose, a common bit length u is determined in advance, and all unit data Ui have the same bit length u. It is preferable that the data has

  The common bit length u can be set to an arbitrary value. However, in practice, u = m × n is set so that a unit bit matrix of m rows and n columns can be formed. The generation unit 120 may divide the digital data into unit data composed of (m × n) bits. Here, for convenience of explanation, an example in which u = 25 bits is set so that a unit bit matrix of 5 rows and 5 columns can be configured by setting m = n = 5 (practically, u The value is preferably set to a larger value). The first unit data U1 shown in FIG. 2 is unit data generated based on such settings, and is composed of 25-bit data.

  For example, the unit data generation unit 120 may divide the input digital data D by dividing it into u bits from the beginning, and set them as unit data U1, U2, U3,. In this case, if the entire length of the digital data D is not an integral multiple of the bit length u, the length of the last unit data does not reach the bit length u. Therefore, when it is desired to align the lengths of all unit data to the common bit length u, a dummy bit is added to the end of the digital data D so that the overall length is an integral multiple of the bit length u. Adjust it.

  Note that the method of dividing the digital data D is not necessarily limited to a method of dividing the digital data D by a predetermined bit length u from the beginning. For example, when dividing into four, the first, fifth, ninth,. Are extracted as the first unit data U1, the extracted second, sixth, tenth,... Bits as the second unit data U2, and the third, seventh,. A division method such that the third unit data U3 is obtained by extracting the th bit, and the fourth unit data U4 is obtained by extracting the fourth, eighth, twelfth,... Bits. It is also possible to take.

  The individual unit data Ui generated by the unit data generation unit 120 is given to the unit bit matrix generation unit 130. The unit bit matrix generation unit 130 performs a process of generating a unit bit matrix B (Ui) by arranging data bits constituting each unit data Ui in a two-dimensional matrix of m rows and n columns.

  In FIG. 2, the 25-bit data constituting the first unit data U1 is divided into 5 bits from the beginning, and “11101”, “10110”, “010001”, “11001”, “10110” 5 An example is shown in which a unit bit matrix B (U1) consisting of a matrix of 5 rows and 5 columns in which groups are formed and individual groups are arranged in one row is shown. Of course, the unit bit matrices B (U2), B (U3), and B (U4) are generated for the unit data U2, U3, and U4 by the same method.

  The individual unit bit matrix B (Ui) generated by the unit bit matrix generation unit 130 in this way is given to the unit bit figure pattern generation unit 140. The unit bit figure pattern generation unit 140 converts each unit bit matrix B (Ui) into a geometric pattern arranged in a predetermined bit recording area on a two-dimensional plane, thereby generating a unit bit figure pattern. A process of generating P (Ui) is performed.

  The middle part of FIG. 2 shows an example of a unit bit figure pattern P (U1) created based on a unit bit matrix B (U1) consisting of a 5 × 5 matrix. In this example, a square bit recording area Ab (area shown by a broken line in the figure) is defined on a two-dimensional plane, and a small square dot (hereinafter referred to as a bit figure) painted black is placed therein. As a result, the unit bit figure pattern P (U1) is formed.

  Here, each bit figure corresponds to the bit “1” constituting the unit bit matrix B (U1). In other words, a 5 × 5 matrix is defined in the bit recording area Ab corresponding to the unit bit matrix B (U1), and corresponds to the bit “1” in the unit bit matrix B (U1). A bit figure is arranged only at the position, and nothing is arranged at the position corresponding to the bit “0”. Therefore, this unit bit figure pattern P (U1) expresses 25-bit information constituting the unit bit matrix B (U1) by the presence or absence of the bit figure at each position constituting the 5 × 5 matrix. It will be.

  Of course, each bit figure may be arranged in correspondence with the bit “0” constituting the unit bit matrix B (U1). In this case, the bit figure is arranged only at the position corresponding to the bit “0” in the unit bit matrix B (U1), and nothing is arranged at the position corresponding to the bit “1”. In short, the unit bit figure pattern generation unit 140 converts any one of the individual bits “1” and individual bits “0” constituting the unit bit matrix B (U1) into individual bit figures formed of a closed region. The process of converting to Note that the format of data indicating individual bit figures may be any format. For example, if one bit figure is composed of rectangles, the coordinate values of the four vertices of each bit figure (or the coordinate values of two diagonal vertices) may be used as data indicating the unit bit figure pattern P (U1). Can be used, or data indicating the coordinate value of the center point (or lower left corner point, etc.) of each bit graphic and data indicating the length of the horizontal and vertical sides of the bit graphic having a common rectangular shape Can also be used. Alternatively, if a circular bit graphic is employed, data indicating the coordinate value of the center point of each bit graphic and data indicating a common radius value can be used.

  Of course, the unit bit matrices B (U2), B (U3), and B (U4) generated for the unit data U2, U3, and U4 are also converted into a geometric pattern by the same method, and the unit bit figure pattern P (U2), P (U3), and P (U4) are generated. If the unit bit figure patterns P (U1) to P (U4) generated in this way are formed on the medium by some method, the information of the digital data D can be recorded on the medium. However, in the invention of the prior application, in consideration of the convenience of the reading process performed later, alignment marks are added to the unit bit figure patterns P (U1) to P (U4), respectively.

  The unit recording graphic pattern generation unit 150 is a component that adds the alignment mark. In the present application, the unit bit graphic pattern P (Ui) with the alignment mark added is used as the unit recording graphic. This is called pattern R (Ui). Eventually, the unit recording graphic pattern generation unit 150 adds an alignment mark to the unit bit graphic pattern P (Ui) generated by the unit bit graphic pattern generation unit 140 to generate a unit recording graphic pattern R (Ui). Processing will be performed.

  The middle part of FIG. 2 shows an example in which a unit recording graphic pattern R (U1) is generated by adding cross-shaped alignment marks Q to the outer four corners of the unit bit graphic pattern P (U1). Here, an area including the bit recording area Ab (dashed square) in which the unit bit figure pattern P (U1) is formed and the alignment marks Q arranged at the four outer corners is defined as a unit recording area Au ( It will be called a one-dot chain line square). The unit recording graphic pattern R (U1) is a graphic pattern formed in the unit recording area Au.

  The alignment mark Q is used for recognizing individual bit recording areas Ab in the reading process described in §3. Therefore, the alignment mark Q is arranged at a specific position with respect to the bit recording area Ab (in the illustrated example, positions at the four outer corners of the bit recording area Ab). In the example shown in the figure, an example using a cross-shaped alignment mark Q is shown, but a figure that can be distinguished from a bit figure representing each bit (in the example shown, a small black square). Any shape can be used as long as it is.

  In the illustrated example, the alignment mark Q is arranged outside the bit recording area Ab. However, the alignment mark Q can be arranged inside the bit recording area Ab. However, in the case of being arranged inside the bit recording area Ab, there is a possibility of interference with bit figures representing individual bits. Therefore, in practice, an alignment mark is placed outside the bit recording area Ab as shown in the example in the figure. Q is preferably arranged. Variations in the shape and arrangement of the alignment mark Q will be described again in §4.

  Thus, when the unit recording graphic pattern generation unit 150 generates four sets of unit recording graphic patterns R (U1) to R (U4), the drawing data generation unit 160 generates drawing data E for drawing them. Generate the process. Specifically, as shown in the lower part of FIG. 2, the drawing data generation unit 160 arranges four sets of unit recording areas R (U1) to R (U4) in a two-dimensional matrix ( In the case of this example, a drawing pattern P (E) including all four sets of unit recording graphic patterns R (U1) to R (U4) is generated, and the drawing pattern P (E ) To generate drawing data E for drawing.

  The processing functions of the individual components of the storage processing computer 100 shown in FIG. 1 have been described above. The drawing data E generated in this way is given to the beam exposure apparatus 200. The beam exposure apparatus 200 is an apparatus that performs beam exposure on the exposure target substrate S based on the drawing data E. The beam exposure apparatus 200 is an electron beam drawing apparatus or laser drawing for semiconductor photolithography that is used in various electronic device manufacturing processes. It can be configured using an apparatus. When an electron beam drawing apparatus is used as the beam exposure apparatus 200, a drawing pattern P (E) is drawn on the surface of the exposure target substrate S by an electron beam, and when a laser drawing apparatus is used as the beam exposure apparatus 200, A drawing pattern P (E) is drawn on the surface of the exposure target substrate S by a laser beam.

  In FIG. 2, for convenience of description, the outline of the bit recording area Ab is indicated by a broken line, and the outline of the unit recording area Au is indicated by a one-dot chain line. ) Is not a component. The graphic pattern actually drawn on the exposure target substrate S is a bit graphic representing each bit (in the example shown, a small black square) and a cross-shaped alignment mark Q.

  Thus, since the drawing data E is data used to give the drawing pattern P (E) on the exposure target substrate S by giving it to the beam exposure apparatus 200, the data format is the beam exposure to be used. It is necessary to make it dependent on the device 200. Currently, when an arbitrary graphic pattern is drawn using an electron beam drawing apparatus or a laser drawing apparatus used in general LSI design, vector-type drawing data indicating the contour line of the graphic pattern is used. . Therefore, in practice, the drawing data generation unit 160 may generate the drawing data E indicating the contour lines of individual bit figures and alignment marks.

  FIG. 3 is an enlarged view of the unit recording graphic pattern R (U1) shown in FIG. In FIG. 2, an example of a small square filled with black is shown as a bit figure indicating the bit “1”. However, in the example shown in FIG. 3, each bit figure F is expressed as vector data indicating a square outline. Is done. Similarly, the alignment marks Q1 to Q4 arranged at the four corners are expressed as vector data indicating a cross-shaped outline. The beam exposure apparatus 200 performs a process of performing beam exposure on the inner portion of the contour line based on the drawing data E indicating the contour lines of the individual bit figures F and the alignment marks Q1 to Q4. Therefore, as shown in FIG. 2, a square or cross-shaped graphic pattern painted black is formed on the exposure target substrate S.

  In FIG. 3, horizontal grid lines X1 to X7 arranged at equal intervals and vertical grid lines Y1 to Y7 arranged at equal intervals are drawn. Each of these grid lines plays a role of determining the arrangement positions of the individual bit figures F and the alignment marks Q1 to Q4. That is, if each intersection of the horizontal grid lines X1 to X7 and the vertical grid lines Y1 to Y7 is referred to as a grid point L, each bit figure F and the alignment marks Q1 to Q4 have any center. It arrange | positions so that it may come to the position of the lattice point L of.

  For example, the alignment mark Q1 is disposed on the lattice point where the lattice lines X1 and Y1 intersect, the alignment mark Q2 is disposed on the lattice point where the lattice lines X1 and Y7 intersect, and the alignment mark Q3 is disposed on the lattice line. The alignment mark Q4 is disposed on the lattice point where the lattice lines X7 and Y7 intersect, and the alignment mark Q4 is disposed on the lattice point where X7 and Y1 intersect.

  25 lattice points at which the five horizontal lattice lines X2 to X6 and the five vertical lattice lines Y2 to Y6 intersect each other are the unit bit matrix B (5 × 5) shown in the middle of FIG. U1), the bit figure F is arranged at the grid point position corresponding to the bit “1” in the unit bit matrix B (U1) (as described above, the grid point position corresponding to the bit “0”). In addition, the bit figure F may be arranged).

  Explaining in general terms, the unit bit figure pattern generation unit 140 is a grid point in which individual bits constituting a unit bit matrix B (Ui) having m rows and n columns are arranged in a matrix of m rows and n columns. The unit bit figure pattern P (Ui) may be generated by arranging the bit figure F having a predetermined shape on the lattice point L corresponding to the bit “1” or the bit “0” in association with L.

  Of course, the figure included in the actual drawing data E, that is, the figure included in the drawing pattern P (E) is only the individual bit figure F and the individual alignment marks Q1 to Q4. The lattice lines X1 to X7, Y1 to Y7, the contour line (broken line) of the bit recording area Ab, and the contour line (one-dot chain line) of the unit recording area Au are not actually drawn.

  The drawing data E includes information indicating the actual size of the drawing pattern P (E) to be drawn on the exposure target substrate S. This actual size indicates the drawing accuracy of the beam exposure apparatus 200 to be used. This should be set in consideration.

  Currently, a pattern having a size of about 40 nm can be stably formed on the substrate S by patterning using a high-precision electron beam drawing apparatus used in general LSI design. Therefore, when such an electron beam drawing apparatus is used as the beam exposure apparatus 200, the lattice line interval (pitch of the lattice point L) shown in the figure can be set to about 100 nm, and a bit figure F having a side of about 50 nm. Is sufficiently possible to form. When drawing such a fine graphic pattern, the bit graphic F actually does not become an accurate square, and the alignment marks Q1 to Q4 do not become an accurate cross, but there is no practical problem. .

  In the first place, the bit figure F only needs to play the role of determining the binary state of whether or not a figure is present at the position of the lattice point L, so the shape may be a rectangle, a circle, or an arbitrary shape. Further, since the alignment marks Q1 to Q4 need only serve to indicate the position of the bit recording area Ab, the shape may be any shape as long as it can be distinguished from the bit graphic F. Therefore, if an electron beam drawing apparatus having a performance capable of stably forming a figure having a size of about 40 nm is used, the bit figure F can be arranged at a pitch of about 100 nm vertically and horizontally as described above. Thus, information recording with a high degree of integration becomes possible.

  On the other hand, when a laser drawing apparatus is used as the beam exposure apparatus 200, the spot diameter of the laser beam depends on the wavelength of the laser beam to be used, and its minimum value is about the same as the wavelength. For example, when an ArF excimer laser is used, since the spot diameter is about 200 nm, the degree of integration of information recording is slightly reduced as compared with the case where an electron beam drawing apparatus is used. Information recording with the same degree of integration as the medium is possible.

  In the case of the example shown in FIG. 3, the unit bit figure pattern P (U1) is a pattern arranged in a rectangular (square) bit recording area Ab, and alignment marks Q1 to Q4 are added thereto. The unit recording figure pattern R (U1) formed by doing so is also a pattern arranged in a rectangular (square) unit recording area Au. In carrying out the invention of the prior application, the bit recording area Ab and the unit recording area Au do not necessarily have to be rectangular areas, but as shown in the lower part of FIG. 2, a plurality of unit recording graphic patterns R (U1 ) To R (U4) are arranged side by side to generate the drawing pattern P (E), it is efficient to make both the bit recording area Ab and the unit recording area Au rectangular.

  Therefore, practically, the unit bit graphic pattern generation unit 140 generates a unit bit graphic pattern P (Ui) arranged in the rectangular bit recording area Ab, and the unit recording graphic pattern generation unit 150 By adding alignment marks Q1 to Q4 outside the rectangular bit recording area Ab, unit recording arranged in the rectangular unit recording area Au including the bit recording area Ab and the alignment marks Q1 to Q4 It is preferable to generate the figure pattern R (Ui) for use. Then, the drawing data generation unit 160 arranges these rectangular unit recording areas Au in a two-dimensional matrix, thereby drawing including a plurality of unit recording graphic patterns R (U1) to R (U4). The pattern P (E) can be generated, and the drawing data E for drawing the drawing pattern P (E) can be generated.

  The size of the unit recording area Au may be set arbitrarily. For example, in the example shown in FIG. 3, if a unit recording area Au consisting of a square with a side of 50 μm is defined and bit figures F are arranged at a pitch of about 100 nm in length and width, one unit recording area Au is included. About 30 KB of information can be recorded. Therefore, for example, if a square substrate having a side of about 150 mm is used as an information recording medium, and unit recording areas Au each consisting of a square having a side of 50 μm are arranged on the two-dimensional matrix, the information recording medium Data of as much as 270 GB can be recorded on one sheet.

<<< §2. Formation of physical structure pattern on medium >>
Here, the exposure process by the beam exposure apparatus 200 shown in FIG. 1 and the patterning process by the patterning apparatus 300 will be described in more detail. As described in §1, the beam exposure apparatus 200 is an apparatus that performs beam exposure using an electron beam or a laser beam on the substrate S serving as an information recording medium based on the drawing data E. The patterning apparatus 300 The apparatus generates an information recording medium on which a physical structure pattern (drawing pattern P (E)) corresponding to the drawing data E is formed by performing a patterning process on the exposed substrate S.

  In practice, these apparatuses can be used as they are for semiconductor lithography used in the LSI manufacturing process. In other words, the beam exposure process by the beam exposure apparatus 200 and the patterning process by the patterning apparatus 300 can be performed by using a conventional general LSI manufacturing process as it is. However, the drawing data used when manufacturing an LSI is data indicating a graphic pattern for constituting each region of a semiconductor element such as a channel region, a gate region, a source region, a drain region, and a wiring region. On the other hand, the drawing data E used in the invention of the prior application is data indicating a bit figure F indicating the data bit “1” or “0” and a figure pattern for constituting the alignment mark Q used at the time of reading. Become.

  FIG. 4 is a side sectional view showing a specific example of the exposure process by the beam exposure apparatus 200 and the patterning process by the patterning apparatus 300 shown in FIG. 1 (only the cut surface is shown, and the back structure is not shown). First, an exposure target substrate S as shown in FIG. In the case of this example, the exposure target substrate S is composed of the molding layer 10 and the resist layer 20. Although an example using a single-layer resist layer 20 is shown here, a resist layer composed of two or more layers may be used when necessary in a patterning step described later. In addition to an organic film such as a resist, an inorganic film such as a metal film (a so-called hard mask that functions as an etching stopper) may be used together.

  Here, the layer to be molded 10 is a layer to be molded in the patterning step, and is finally a portion that becomes an information recording medium M on which digital data is recorded. As described above, the purpose of the invention of the prior application is to enable information recording to maintain long-term durability. Therefore, the molded layer 10 includes a substrate made of a material suitable for achieving such an object. Can be used. Specifically, as the transparent material, it is optimal to use a glass substrate, particularly a quartz glass substrate, as the molding layer 10. Of course, an opaque material such as a silicon substrate can be used as the molding layer 10. Inorganic materials such as a quartz glass substrate and a silicon substrate are materials that are not easily damaged by physical damage and are not susceptible to chemical contamination, and are optimal materials for use in the information recording medium of the prior invention.

  On the other hand, as the resist layer 20, a material suitable for patterning the layer to be molded 10 may be used. That is, a material whose composition changes by exposure to an electron beam or a laser beam and that functions as a protective film in the etching process for the layer to be molded 10 may be used. Of course, a positive resist having the property of dissolving the exposed portion during development may be used, or a negative resist having a property of dissolving the non-exposed portion during development may be used.

  The shape and size of the exposure target substrate S may be arbitrary. At present, a quartz glass substrate that is generally used as a photomask is often a standard rectangular substrate of 152 × 152 × 6.35 mm. Further, as the silicon substrate, a disk-shaped wafer having a thickness of about 1 mm in accordance with a standard such as a diameter of 6 inches, 8 inches, or 12 inches is often used. As the exposure target substrate S, a substrate in which these standard substrates are formed layers 10 and a resist layer 20 is formed on the upper surface thereof may be used.

  Hereinafter, for convenience of explanation, an example in which a quartz glass substrate is used as the molding layer 10 and a positive resist is used as the resist layer 20 will be described. Therefore, the exposure target substrate S shown in FIG. 4A is a substrate in which the positive resist layer 20 is formed on the quartz glass substrate 10. Of course, the invention of the prior application is not limited to such an embodiment.

  After all, the beam exposure apparatus 200 shown in FIG. 1 performs beam exposure on the surface of the resist layer 20 on the exposure target substrate S having the layer to be molded 10 and the resist layer 20 covering the layer to be molded 10. FIG. 4B shows an exposure process by the beam exposure apparatus 200. As described in §1, the exposure by the beam exposure apparatus 200 is performed only on the inside of the bit figure F and the inside of the alignment mark Q. Therefore, the resist layer 20 is divided into an exposed portion 21 and a non-exposed portion 22 through an exposure process. Here, the chemical composition of the non-exposed portion 22 remains the same, but the chemical composition of the exposed portion 21 changes.

  The patterning device 300 is a device that performs patterning on the substrate S after such an exposure process is completed, and includes a development processing unit 310 and an etching processing unit 320 as shown in FIG.

  The development processing unit 310 is a substrate after exposure in a developer having a property of dissolving the exposed portion 21 (when using a positive resist) or the non-exposed portion 22 (when using a negative resist) of the resist layer. A development process is performed in which S is impregnated and a part of the S is impregnated. FIG. 4 (c) shows a state in which such development processing is performed on the substrate S shown in FIG. 4 (b). In the embodiment shown here, since a positive resist is used, the exposed portion 21 is dissolved in the developer by the developing process, and the non-exposed portion 22 remains as the remaining portion 23.

  On the other hand, the etching processing unit 320 performs an etching process on the substrate S after development. In the case of the embodiment shown in FIG. 4C, the etching process is performed on the layer to be molded 10 using the remaining portion 23 as a mask. Specifically, the substrate S shown in FIG. 4 (c) may be impregnated with an etchant whose corrosiveness to the molding layer 10 is stronger than the corrosiveness to the remaining portion 23 of the resist layer (of course, dry etching). For example, a method that does not impregnate the etching solution may be used).

  FIG. 4D shows a state where the etching processing by the etching processing unit 320 has been performed. Of the upper surface of the layer 10 to be molded, the portion covered with the remaining portion 23 serving as a mask is not corroded, but the exposed portion is corroded to form a recess. Thus, the molding layer 10 is processed into the molding layer 11 having an uneven structure on the upper surface. Thereafter, the etching processing unit 320 has a processing function of peeling and removing the remaining portion 23 of the resist layer and cleaning and drying the layer 11 to be molded.

  Through such a process, the processed layer 11 after processing as shown in FIG. 4 (e) is finally obtained. The molded layer 11 thus obtained is nothing but the information recording medium M1 on which the digital data is written by the information storage device according to the invention of the prior application. As shown in the figure, a physical concavo-convex structure is formed on the upper surface of the information recording medium M1, and the bit “1” and the bit “0” are expressed by the concave portion C and the convex portion V. Therefore, by detecting whether the medium surface constitutes a concave portion C or a convex portion V at a position indicated by a thick dashed line in the figure (a position corresponding to the lattice point L shown in FIG. 3), Bit “1” and bit “0” can be read.

  Of course, contrary to the illustrated example, it is also possible to adopt a recording method in which the concave portion C is set to the bit “0” and the convex portion V is set to the bit “1”. Which is set to bit “0” and which is set to bit “1” is a matter determined according to the processes described so far. For example, in the case of the example described in §1, the unit bit graphic pattern generation unit 140 arranges the bit graphic F at the position of the grid point L corresponding to the bit “1” of the unit bit matrix. If the bit figure F is arranged at the position of the lattice point L corresponding to the bit “0”, the bit information of the concave portion and the convex portion is reversed. Further, when a negative resist is used as the resist layer 20 instead of a positive resist, the relationship between the concave portion and the convex portion is reversed.

  The information recording medium M1 thus prepared has long-term durability, information recording is performed with a high degree of integration, and information can be read out by a universal method.

  That is, when a material such as a quartz glass substrate or a silicon substrate is used as the layer to be molded 10, deterioration due to secular change and the action of water and heat, compared to conventional information recording media such as paper, film, and record board, etc. It is less likely to be damaged by, and can be durable on a semi-permanent time scale of hundreds of years, just like ancient stones. Needless to say, the durability can be obtained over a much longer period of time as compared with a magnetic recording medium, an optical recording medium, a semiconductor recording medium or the like generally used as a data recording medium for computers. Therefore, the invention of the prior application is optimal for use in storing information such as an official document for which information should be recorded semipermanently.

  Further, as described in Section 1, the beam exposure apparatus 200 can perform fine exposure with an electron beam or a laser beam, so that information recording can be performed with a very high degree of integration. For example, if a high-definition electron beam drawing apparatus is used, the bit figure F can be written at a pitch of about 100 nm, and a capacity of about 100 GB to 1 TB can be added to the above-described standard size photomask or silicon substrate. It becomes possible to save the information.

  Furthermore, the information recording medium according to the invention of the prior application has a feature that information can be read out by a universal method because binary information of bits is directly recorded as a physical structure such as unevenness. That is, Patent Documents 1 and 2 listed above disclose a technique for recording information three-dimensionally using a cylindrical quartz glass as a medium, but recorded three-dimensionally in the medium. In order to read out information, a dedicated reading device using computer tomography or the like is required, and special arithmetic processing such as Fourier transform processing is required. Therefore, for example, even if a cylindrical recording medium remains intact after several hundred years, information cannot be read out unless the technique of a dedicated reading device is inherited.

  On the other hand, since the binary information of bits is directly recorded as a physical structure on the information recording medium created by the information storage device according to the invention of the prior application, the recording surface is enlarged by some method. Can be read out, at least the bit information itself can be read out. In other words, the information recording medium according to the invention of the prior application itself is a three-dimensional structure, but since the bit information is recorded two-dimensionally, the information recording medium according to the invention of the prior application is Even if excavated after hundreds of years or thousands of years, bit information can be read out by a universal method.

  As described above, by the information storage device according to the invention of the prior application, the concavo-convex structure including the concave portion indicating one of the bits “1” and the bit “0” and the convex portion indicating the other on the surface of the quartz glass substrate or the silicon substrate An example of forming a physical structure pattern having was described. However, in carrying out the invention of the prior application, the physical structure indicating the bit information is not necessarily limited to the uneven structure. Therefore, several variations of the method of forming a physical structure on the medium will be described with reference to the side cross-sectional view of FIG. 5 (only the cut surface is shown, and the illustration of the back structure is omitted).

  FIG. 5A shows a physical structure pattern having a network structure composed of a through hole H indicating one of the bits “1” and a bit “0” and a non-hole portion N indicating the other by the patterning device 300. It is a sectional side view which shows the example formed. In the network structure 12 shown in the figure, a position indicated by a thick one-dot chain line is a position corresponding to the lattice point L shown in FIG. 3, and the position is a through hole H or a non-hole portion N (a through hole is formed). The bit “1” and the bit “0” are represented as shown in FIG.

  Thus, in the case of the information recording medium shown in FIG. 5 (a), since the bits are expressed not by the concavo-convex structure but by the presence or absence of the through holes, the medium itself constitutes a network structure. The basic principle of recording bit information at the position of the point L is exactly the same as the basic embodiment shown in FIG. Of course, the bit “0” may be expressed by the through hole H, and the bit “1” may be expressed by the non-hole portion N. When the network structure 12 shown in FIG. 5A is used as the information recording medium M, the etching process is continued until the bottom surface of the layer to be molded 10 is reached in the etching process (FIG. 4D) by the etching processing unit 320. The through hole H may be formed.

  On the other hand, FIGS. 5B to 5D are side cross-sectional views showing modifications in which additional layers are formed on the surface of the concave portion C or the convex portion V of the information recording medium M1 shown in FIG. is there. In the case of the modification shown in FIG. 5 (b), the additional layer 31 is formed on the surfaces of both the recess C and the protrusion V. In the case of the modification shown in FIG. Only the additional layer 32 is formed. In the modification shown in FIG. 5D, the additional layer 33 is formed only on the surface of the recess C.

  As the additional layers 31, 32, 33, light reflecting materials (for example, metals such as aluminum, nickel, titanium, silver, chromium, silicon, molybdenum, platinum, alloys of these metals, oxides, nitrides, etc.) Alternatively, a light-absorbing material (for example, a material made of a compound such as a metal oxide or nitride. For example, chromium oxide or chromium nitride can be used as an example of chromium). If an additional layer made of a light-reflective material is formed, the concave portion C and the convex portion V can be distinguished based on the difference in behavior of reflected light during reading, and the additional layer made of a light-absorbing material. , The concave portion C and the convex portion V can be distinguished from each other based on the difference in the light absorption mode at the time of reading. Therefore, if such an additional layer is formed, an effect of facilitating reading of information can be obtained.

  Further, instead of forming another layer having a clear boundary surface such as an additional layer, the same effect can be obtained by doping impurities on the surface of the concave portion C or the convex portion V. For example, when an information recording medium having a concavo-convex structure is made of quartz, and the surface is doped with boron, phosphorus, rubidium, selenium, copper, etc., and the impurity concentration of the surface portion is varied, an additional layer is provided. Similarly, the surface portion can have light reflectivity or light absorbability, and an effect of facilitating reading of information can be obtained. Specifically, in the case of the impurity in the above example, when the concentration is about 100 ppm or more, an ultraviolet absorption effect is obtained, and when the concentration is about 1000 ppm or more, an effect of increasing the reflectance is obtained.

  In particular, as in the example shown in FIG. 5C, if the additional layer 32 made of a light-reflective or light-absorbing material is formed only on the convex portion V, the reflection obtained from the concave portion C at the time of reading. Since the difference between the light or scattered light and the reflected light or scattered light obtained from the convex portion V becomes significant, the bit “1” and the bit “0” can be easily identified. Similarly, even when the additional layer 33 made of a light-reflective or light-absorbing material is formed only in the concave portion C as in the example shown in FIG. 5D, the reflection obtained from the concave portion C at the time of reading. Since the difference between the light or scattered light and the reflected light or scattered light obtained from the convex portion V becomes significant, bit identification is facilitated.

  In order to form the additional layer 31 on the surface of both the concave portion C and the convex portion V as in the example shown in FIG. 5B, after the information recording medium M1 shown in FIG. Further, a process for depositing the additional layer 31 on the entire upper surface of the recording medium may be performed. Further, as in the example shown in FIG. 5C, in order to obtain a structure in which the additional layer 32 is formed only on the surface of the convex portion V, instead of the exposure target substrate S shown in FIG. A substrate having a structure in which an additional layer is sandwiched between the molding layer 10 and the resist layer 20 may be used. Then, as in the example shown in FIG. 5 (d), in order to obtain a structure in which the additional layer 33 is formed only on the surface of the recess C, the resist layer is formed when the etching process shown in FIG. 4 (d) is completed. The remaining portion 23 is left as it is, and an additional layer is deposited on the entire upper surface, and then the remaining portion 23 is peeled off.

  On the other hand, in the modification shown in FIG. 5 (e), the layer 51 itself formed on the upper surface of the support layer 40 is made of a light-reflective or light-absorbing material. For example, if the support layer 40 is made of a quartz glass substrate, an additional layer made of aluminum is formed on the upper surface thereof, and a resist layer is further formed on the upper surface thereof, and a process according to the process illustrated in FIG. A structure as shown in FIG. 5 (e) can be obtained. In this case, the etching process may use a corrosive liquid that is corrosive to aluminum. In this structure, the surface of the concave portion C is made of quartz glass, and the surface of the convex portion V is made of aluminum, so that an effect of facilitating bit identification at the time of reading can be obtained.

  In practice, when the modification shown in FIG. 5 (a) is adopted, it is preferable that the network structure 12 is made of an opaque material. By doing so, the portion of the through-hole H becomes a portion that transmits light, and the portion of the non-hole portion N becomes a portion that does not transmit light. Becomes easier.

  On the other hand, when the modification shown in FIGS. 5C to 5E is employed, the molding layer 11 or the support layer 40 is made of a transparent material, and the additional layers 32, 33, 51 are made of an opaque material. It is preferable to do this. Then, the portion where the additional layer is not formed becomes a portion that transmits light, and the portion where the additional layer is formed becomes a portion that does not transmit light. The difference can be recognized and the bit can be easily identified.

<<< §3. Basic embodiment of information reading apparatus according to prior invention >>>
In §1 and §2, the configuration and operation of the information storage device for storing information in the information recording medium has been described. Here, the configuration and operation of the information reading apparatus used for reading the information thus recorded will be described.

  FIG. 6 is a block diagram showing the configuration of the basic embodiment of the information reading apparatus according to the invention of the prior application. The information reading device according to this embodiment is a device that performs the function of reading digital data stored in the information recording medium M using the information storage device shown in FIG. 1, and as shown in FIG. The computer 500 is configured.

  Here, the image capturing apparatus 400 is a component that captures an image of an image capturing area that forms part of the recording surface of the information recording medium M and captures the obtained captured image as image data. An image sensor 410, an enlargement optical system 420, and a scanning mechanism 430 are included.

  The image sensor 410 can be constituted by a CCD camera, for example, and has a function of capturing an image in a predetermined photographing target area as digital image data. The magnifying optical system 420 is composed of an optical element such as a lens. The magnifying optical system 420 enlarges a predetermined imaging target area that constitutes a part of the recording surface of the information recording medium M and forms the enlarged image on the imaging surface of the imaging element 410 Fulfill. The scanning mechanism 430 performs a scanning process (change of position and angle) on the image sensor 410 and the magnifying optical system 420 so that the imaging target area sequentially moves on the recording surface of the information recording medium M. Fulfill.

  FIG. 5 shows a variation of the information recording medium M. However, the information recording medium M including the network structure 12 shown in FIG. The information can also be read out for both, and the upper and lower surfaces constitute the recording surface. On the other hand, as shown in FIGS. 4E and 5B to 5E, in the case of the information recording medium M having the concavo-convex structure formed on the upper surface, the upper surface is the recording surface. Therefore, when the molding layer 11 or the support layer 40 is made of a transparent material, information can be read out from any of the upper and lower sides, but these are made of an opaque material. If it is, it is necessary to shoot from above.

  The read processing computer 500 includes a captured image storage unit 510, a bit recording area recognition unit 520, a unit bit matrix recognition unit 530, a scanning control unit 540, and a data restoration unit 550, as illustrated. Hereinafter, functions of these units will be described in order. However, each of these units is actually a component realized by incorporating a dedicated program into the computer, and the read processing computer 500 can be configured by installing a dedicated program on a general-purpose computer. it can.

  First, the captured image storage unit 510 is a component that stores a captured image captured by the image capturing apparatus 400. That is, it has a function of storing an image in a predetermined shooting target area shot by the imaging element 410 as digital image data. As described above, the image capturing apparatus 400 is provided with the scanning mechanism 430, and the image capturing target area sequentially moves on the recording surface of the information recording medium M. A captured image is acquired. The captured image storage unit 510 functions to store the image data sequentially given from the image sensor 410 in this way.

  On the other hand, the bit recording area recognition unit 520 performs processing for recognizing individual bit recording areas Ab from the captured image stored in the captured image storage unit 510. In the prior invention, as described with reference to FIG. 2, the digital data D to be stored is divided into a plurality of unit data U1, U2, U3,..., Which are unit bit graphic patterns P (U1), P (U2), P (U3),... Are recorded in the individual bit recording areas Ab. Therefore, at the time of read processing, first, each bit recording area Ab is recognized, and then each bit constituting the unit data Ui is based on the individual unit bit figure pattern P (Ui) recorded therein. Will be read out.

  As described in §2, an alignment mark Q and a bit figure F are recorded on the recording surface of the information recording medium M as a physical structure pattern such as a concavo-convex structure or the presence or absence of a through hole. For this reason, the alignment mark Q, the bit figure F, or the outline thereof is expressed as a light and dark distribution on the photographed image, and the position on the photographed image can be obtained by using the existing pattern recognition technology. It is possible to recognize the alignment mark Q and the bit figure F.

  First, each bit recording area Ab is recognized by detecting the alignment mark Q. Since a graphic different from the bit graphic F is used for the alignment mark Q, the bit recording area recognition unit 520 searches the captured image stored in the captured image storage unit 510 to perform alignment. The mark Q can be detected. For example, in the example shown in the lower part of FIG. 2, the bit figure F is a square, whereas the alignment mark Q is a cross shape. It is possible to recognize the alignment mark Q and determine its position.

  Since the alignment mark Q is arranged at a specific position with respect to the bit recording area Ab, if the alignment mark Q can be recognized on the captured image, the position of the bit recording area Ab can be specified. . For example, if a unit recording graphic pattern R (U1) as shown in FIG. 3 is included in the photographed image, if four sets of alignment marks Q1 to Q4 can be recognized, these four sets of positions will be recognized. A square-shaped bit recording area Ab having alignment marks Q1 to Q4 in the vicinity of the four corners can be recognized.

  If the image photographing device 400 has a function of photographing a photographing target area having a size that can include at least one unit recording area Au, four sets as shown in FIG. The alignment marks Q1 to Q4 can be recognized, and the bit recording area Ab can be recognized.

  Of course, if the shooting target area is set at a position that is crotch to the unit recording area Au adjacent to each other, the four sets of alignment marks Q1 to Q4 indicating the position of the same bit recording area Ab cannot be recognized correctly. . In this case, the bit recording area recognizing unit 520 can grasp the positional deviation of the imaging target area based on the reciprocal relationship of the recognized alignment marks, and therefore reports the positional deviation to the scanning control unit 540. Perform the process.

  When the scanning control unit 540 receives such a positional deviation report, the scanning control unit 540 controls the image capturing apparatus 400 to adjust the positional deviation. Specifically, the scanning mechanism 430 is instructed to move the imaging target area in a predetermined correction direction by a predetermined correction amount. By performing such adjustment, as shown in FIG. 3, it is possible to obtain a correct captured image in which the alignment marks Q1 to Q4 are arranged at appropriate positions at the four corners, which is correct with respect to the bit recording area Ab. Reading processing can be performed. As described above, the first role of the scanning control unit 540 is an adjustment process for correcting the positional deviation when the photographing target area has a positional deviation with respect to the unit recording area Au.

  The second role of the scanning control unit 540 is scanning processing for setting the next unit recording area Au as a new imaging target area after the imaging with one unit recording area Au as the imaging target area is completed. For example, in the case of the example shown in the lower part of FIG. 2, when photographing of the unit recording area Au (U1) in which the unit recording graphic pattern R (U1) is recorded is completed, the unit recording graphic pattern R ( The unit recording area Au (U2) in which U2) is recorded needs to be photographed, and then the unit recording area Au (U3) in which the unit recording graphic pattern R (U3) is recorded, and the unit It is necessary to move the photographing target area sequentially with the unit recording area Au (U4) where the recording graphic pattern R (U4) is recorded.

  After all, the scanning control unit 540 can be said to be a component that performs control for changing the shooting target area by the image shooting apparatus 400 so that shot images for all the bit recording areas to be read are obtained. This control can be performed by feedback control based on the detection result of the alignment mark Q by the bit recording area recognition unit 520, and fine adjustment as described above is possible even when a positional deviation occurs.

  When the bit recording area recognition unit 520 recognizes the i-th bit recording area Ab (i) from the photographed image, the information of the i-th bit recording area Ab (i) is sent to the unit bit matrix recognition unit 530. Given. The unit bit matrix recognition unit 530 performs processing for recognizing the unit bit matrix based on the pattern in the bit recording area Ab (i). For example, in the case of the example shown in FIG. 3, based on the unit bit figure pattern P (U1) recorded in the bit recording area Ab, a unit bit matrix B having 5 rows and 5 columns as shown in the middle of FIG. (U1) can be recognized.

  In the case of the example shown in FIG. 3, as described in §1, horizontal grid lines X1 to X7 arranged at equal intervals and vertical grid lines Y1 to Y7 arranged at equal intervals are defined. A grid point L is defined as each intersection, and the individual bit figures F and the alignment marks Q1 to Q4 are arranged so that the centers thereof are located at any of the grid points L. Therefore, the recognition process of the unit bit matrix B (U1) by the unit bit matrix recognition unit 530 can be performed by the following procedure.

  First, the horizontal grid lines X1 and X7 and the vertical grid lines Y1 and Y7 are recognized based on the center point positions of the four sets of alignment marks Q1 to Q4 recognized by the bit recording area recognition unit 520. Subsequently, the horizontal grid lines X2 to X6 are defined so as to equally divide the horizontal grid lines X1 and X7, and the vertical grid lines are equally divided between the vertical grid lines Y1 and Y7. Y2 to Y6 are defined. Then, 25 grid point positions where the horizontal grid lines X2 to X6 and the vertical grid lines Y2 to Y6 cross each other are determined, and it is determined whether or not the bit figure F exists at each grid point position. What is necessary is just to process. As described above, since the bit figure F can be recognized based on the light / dark distribution on the photographed image, the bit “1” is associated with the grid point position where the bit figure F exists, and the non-existing grid point position. Is associated with bit “0”, a 5 × 5 unit bit matrix B (U1) shown in the middle of FIG. 2 can be obtained.

  The unit bit matrix recognition unit 530 thus performs the i-th unit bit matrix B based on the i-th unit bit figure pattern P (Ui) recorded in the i-th bit recording area Ab (i). Processing for recognizing (Ui) is performed, and the result is given to the data restoration unit 550. The unit bit matrix recognizing unit 530 repeatedly executes the unit bit matrix recognizing process for all the bit recording areas recognized by the bit recording area recognizing unit 520 in the same manner.

  The data restoration unit 550 generates the unit data Ui from the individual unit bit matrix B (Ui) recognized by the unit bit matrix recognition unit 530 in this way, and synthesizes the individual unit data Ui to thereby store the digital data to be stored. A process for restoring the data D is executed. For example, in the case of the example shown in FIG. 2, four sets of unit data U1 to U4 are generated from four sets of unit bit matrices B (U1) to B (U4), and these are concatenated to generate the original digital data D Will be restored.

  The basic embodiment of the information reading device according to the invention of the prior application has been described above with reference to the block diagram of FIG. 6, but the information from the information recording medium M created by the information storage device according to the invention of the prior application has been described. Reading is not necessarily performed using such an information reading device. For example, information can be read out using an optical measuring instrument, a scanning electron microscope, an atomic force microscope, or the like.

  Since the information recording medium M created by the information storage device according to the invention of the prior application has the universality that binary information of bits is directly recorded as a physical structure as described above, the recording surface is If the image showing the presence or absence of the bit figure F can be obtained by enlarging by some method, the bit information can be read out. Therefore, even when the information recording medium M is excavated after several hundreds of years or thousands of years, it is possible to read bit information if there is any physical structure recognition means in that era. Of course, if it is stored buried in the ground, there is a possibility that foreign matter adheres to the recording surface and is contaminated, but these foreign matter can be easily removed by washing. There is no problem in reading information.

  Regardless of which reading method is used, the information recording surface can be read in a non-contact state (even if an atomic force microscope is used, the non-contact mode is used for reading in a non-contact state. However, the recording surface is not physically damaged during the reading process, and even if the reading process is repeatedly executed, there is no possibility that the information recording surface is worn.

  When the information reading device shown in FIG. 6 is combined with the information storage device shown in FIG. 1, information is read from a part of the recorded area of the information recording medium M, and the unrecorded area adjacent to the recorded area is read. It is also possible to store new information. Therefore, it becomes possible to realize a write-once type information storage apparatus that sequentially records new information on one information recording medium. Of course, if a device that combines an information storage device and an information reading device is used, after performing a storage process for writing information on a medium using the information storage device, verification of the information stored using the information reading device is performed. It can be done, and can be modified as needed.

<<< §4. Variation of alignment mark >>>
In §3, the basic embodiment of the information reading device has been described. Therefore, here, in consideration of the convenience at the time of reading information, variations of the alignment mark to be recorded when information is stored will be described. The bit mark F plays a role of indicating original information to be stored, whereas the alignment mark Q is meta information used for positioning at the time of information reading.

  In the embodiments described so far, the unit recording graphic pattern generation unit 150 has cross-shaped alignment marks Q1 on the outside of the four corners of the rectangular bit recording area Ab, for example, as illustrated in FIG. Processing for generating a unit recording graphic pattern is performed by adding .about.Q4. These alignment marks Q1 to Q4 are used for alignment for the bit recording area recognition unit 520 in the information reading apparatus shown in FIG. 6 to recognize the bit recording area Ab.

  However, the shape, arrangement position, and number of the alignment marks Q are not limited to the above-described embodiment. That is, the shape of the alignment mark Q may be any shape as long as it can be distinguished from the bit graphic F. Further, the positions to be arranged are not necessarily arranged outside the four corners of the bit recording area Ab. For example, they may be arranged at the center positions of the four sides of the bit recording area Ab. Further, the number of alignment marks Q is not necessarily four sets.

  FIG. 7 is a plan view showing a variation of the alignment mark Q used in the prior invention. In both cases, the broken-line square indicates the bit recording area Ab (for convenience, a hatched line is provided instead of drawing a bit figure), and the dashed-dotted square indicates the unit recording area Au. The circular mark arranged at the position is the alignment mark Q.

  FIG. 7A shows an example in which alignment marks Q11 and Q12 are arranged in the vicinity of the upper left corner and the upper right corner of the rectangular bit recording area Ab. If the direction connecting the center points of the two sets of alignment marks Q11 and Q12 is defined as the horizontal coordinate axis X, it is possible to indicate one coordinate axis direction related to the arrangement of the bit recording area Ab. At the time of reading, the horizontal coordinate axis X can be recognized based on the two sets of alignment marks Q11 and Q12, and the vertical coordinate axis Y can be defined as an axis orthogonal to the horizontal coordinate axis X. If the bit recording area Ab has a correct rectangle, no trouble occurs in the reading process of each bit. From this point of view, if two sets of alignment marks are added to one bit recording area Ab, there is no practical problem in reading processing.

  Of course, the vertical coordinate axis Y may be defined by arranging alignment marks near the upper left corner and the lower left corner of the bit recording area Ab. In short, the unit recording graphic pattern generation unit 150 adds a total of two sets of alignment marks arranged in the vicinity of the outer corners of two corners that are not diagonal of the four corners of the rectangular bit recording area Ab. A unit recording figure pattern may be generated.

  On the other hand, FIG. 7B shows a unit by adding a total of three sets of alignment marks Q21, Q22, Q23 arranged near the outside of the three corners of the rectangular bit recording area Ab. This is an example of generating a graphic pattern for recording. If three sets of alignment marks Q21, Q22, and Q23 are used in this way, both the horizontal coordinate axis X and the vertical coordinate axis Y can be defined as shown in the figure, and the accuracy of reading processing of each bit can be further improved. It is possible to increase.

  When three sets of alignment marks are used as described above, the arrangement mode of the three sets of alignment marks is made different for unit recording graphic patterns adjacent to each other as in the example shown in FIG. Is preferred. FIG. 8 shows a state in which a plurality of unit recording areas Au are arranged in a two-dimensional matrix. Here, the unit recording areas Au (11), Au (13), Au (22), Au (31), and Au (33) are omitted in the arrangement mode shown in FIG. In FIG. 7B, the unit recording areas Au (12), Au (21), Au (23), and Au (32) are shown in FIG. Three sets of alignment marks are arranged in an arrangement manner that is reversed left and right with respect to the arrangement manner (that is, an arrangement manner in which only the lower left corner is missing).

  In short, for the arrangement of unit recording areas Au, row numbers i (i = 1, 2, 3,...) And column numbers j (j = 1, 2, 3,. When the unit recording area is expressed as Au (ij) as shown in the figure, the first group in which (i + j) is an even number lacks an alignment mark only at the lower right corner as shown in FIG. For the second group in which (i + j) is an odd number, an arrangement mode in which the alignment mark is missing only at the lower left corner as shown in FIG. 7 (b) is reversed. ing.

  In this way, if two modes are defined as the arrangement modes of the three sets of alignment marks, and the unit recording graphic patterns adjacent to each other in the vertical and horizontal directions adopt different arrangement modes, the scanning control unit When the 540 scans the shooting target area, it is possible to prevent an error that skips shooting for the adjacent unit recording area.

  For example, in the example illustrated in FIG. 8, the scanning control unit 540 first captures the unit recording area Au (11) as an imaging target area, and then moves the imaging target area to the right in the drawing and is adjacent to the right. Assume that control is performed so that the unit recording area Au (12) to be photographed is an imaging target area. Normally, if the control is performed to move the distance corresponding to the pitch of the unit recording area Au, the next shooting target area can be moved to the position of the unit recording area Au (12). However, if an error occurs in the moving distance for some reason and the photographing target area has moved to the position of the unit recording area Au (13), the reading process for the unit recording area Au (12) is skipped. Become.

  If an arrangement mode as shown in FIG. 8 is employed, it is possible to detect an error even if such a situation occurs. That is, if the unit recording area Au (11) is imaged after the unit recording area Au (11) is imaged and the unit recording area Au (13) is imaged, the alignment marks are arranged in the same manner. Therefore, it can be recognized that the unit recording area Au (12) has been skipped. Therefore, it is possible to perform a process for returning the shooting target area to the left in the drawing so that the unit recording area Au (12) is shot. The same correction is possible when a vertical skip occurs.

  As a method for recognizing that such a skip has occurred, it is possible to adopt a method of changing the shape of the alignment mark in addition to a method of preparing two arrangement modes. For example, FIGS. 9A and 9B show an example of a variation in which the shape of the alignment mark is changed. In the case of the example shown in FIG. 9 (a), the cross-shaped mark Q31, the triangular mark Q32, and the square mark Q33 are arranged at the positions shown in the figure, whereas in the example shown in FIG. 9 (b). In this case, a circular mark Q41, a rhombus mark Q42, and a mark Q43 with a cross mark are arranged at the illustrated positions. If such two kinds of alignment marks are used alternately in the vertical and horizontal directions, it is possible to recognize that a skip has occurred as in the example shown in FIG.

  FIG. 10 is a plan view showing still another variation of the arrangement form of the alignment marks in the prior invention. In this variation, the alignment mark for the unit recording area Au (11) in the example shown in FIG. 8 is changed to the alignment mark shown in FIG. 9 (a). That is, only the unit recording area Au (11) arranged in the first row and the first column among the plurality of unit recording areas Au arranged in a two-dimensional matrix has a different alignment mark shape. . This is because the unit recording area Au (11) arranged in the first row and the first column is set as a reference unit recording area to be read out first, and this reference unit recording area can be easily set during the reading process. This is a consideration to enable identification.

  When the variation shown in FIG. 10 is adopted, the unit recording graphic pattern generation unit 150 sets a specific unit recording area as a reference unit recording area, and the reference unit recording area is different from other unit recording areas. A unit recording figure pattern using different reference alignment marks may be generated. In the example shown in the figure, the reference alignment mark shown in FIG. 9A is used for the reference unit recording area Au (11), and the normal alignment mark shown in FIG. 8 is used for the other unit recording areas. Therefore, at the time of the reading process, the reference unit recording area Au (11) to be read first can be specified by first searching for the reference alignment mark shown in FIG. 9A. .

  That is, if the image photographing device 400 in the information reading device shown in FIG. 6 has a function of photographing a region to be photographed having a size that can include at least one unit recording region Au, it is shown in FIG. Since the reference alignment mark can be searched, the scanning control unit 540 first captures an area including the reference unit recording area Au (11) based on the reference alignment mark shown in FIG. In order to obtain an image, the image capturing apparatus 400 may be controlled to adjust the capturing target area. Thus, when the correct bit information is read from the bit recording area Ab (11) in the reference unit recording area Au (11), the scanning control unit 540 sets the imaging target area according to the arrangement pitch of the unit recording areas Au. Control to move sequentially may be performed.

  Of course, in this case as well, as described with reference to FIG. 8, even if an error occurs in which the unit recording area Au (13) is skipped for some reason, the error can be recognized and corrected. Further, fine adjustment can be performed even when a fine positional deviation occurs.

  Further, as a method of indicating the reference unit recording area Au (11), instead of adopting a method of using a reference alignment mark different from the other unit recording areas, a bit recording area Ab (in the reference unit recording area Au (11) is used. 11) It is also possible to adopt a method of arranging a specific identification mark without arranging the bit figure F. The bit recording area Ab is originally an area used for recording the data to be stored by arranging the bit figure F. However, if a specific identification mark is arranged only for the reference unit recording area, By confirming the unique identification mark, the reference unit recording area can be easily recognized.

  For example, if a large star is drawn in the area Au (11) shown in FIG. 8, it can be easily recognized that the area Au (11) is a reference unit recording area. In this case, the original information is not recorded in the area Au (11). First, after the position adjustment with the reference unit recording area Au (11) as the first imaging target area is performed, the imaging target area is set. It is sufficient to perform scanning that sequentially moves. If the size of the reference unit recording area Au is a size that can be visually observed, in the above example, it is possible to visually check the star mark, and the position where the reference unit recording area Au (11) is the first imaging target area. The alignment can also be performed manually by an operator's visual inspection.

<<< §5. Information storage method and information reading method according to the invention of the prior application >>>
Here, a basic processing procedure when the prior invention is grasped as a method invention of an information storage method and an information reading method will be described.

  FIG. 11 is a flowchart showing the basic processing procedure of the information storage method according to the invention of the prior application. This procedure is an execution procedure of an information storage method in which digital data is written and stored on an information recording medium. Steps S11 to S16 are steps executed by the storage processing computer 100 shown in FIG. 1 is a procedure executed by the beam exposure apparatus 200 shown in FIG. 1, and step S18 is a procedure executed by the patterning apparatus 300 shown in FIG.

  First, in step S11, a data input stage is executed in which the storage processing computer 100 inputs digital data D to be stored. In subsequent step S12, the storage processing computer 100 divides the digital data D by a predetermined bit length unit, thereby executing a unit data generation stage for generating a plurality of unit data Ui. In step S13, a unit bit matrix generation stage in which the storage processing computer 100 generates a unit bit matrix B (Ui) by arranging data bits constituting each unit data Ui in a two-dimensional matrix form. In step S14, the storage processing computer 100 converts the unit bit matrix B (Ui) into a geometric pattern arranged in a predetermined bit recording area Ab, thereby converting the unit bit figure pattern P ( A unit bit figure pattern generation step for generating Ui) is executed.

  Subsequently, in step S15, the storage processing computer 100 adds the alignment mark Q to the unit bit graphic pattern P (Ui) to generate the unit recording graphic pattern R (Ui). A generation phase is performed. In step S16, a drawing data generation stage is executed in which the storage processing computer 100 generates drawing data E for drawing the unit recording graphic pattern R (Ui).

  Finally, in step S17, based on the drawing data E, a beam exposure stage is performed in which beam exposure using an electron beam or laser light is performed on the substrate S serving as an information recording medium. In step S18, exposure is performed. By performing a patterning process on the received substrate, a patterning step for generating an information recording medium M on which a physical structure pattern corresponding to the drawing data E is formed is executed.

  On the other hand, FIG. 12 is a flowchart showing the basic processing procedure of the information reading method according to the prior invention. This procedure is an execution procedure of an information reading method for reading digital data stored in the information recording medium M according to the procedure shown in FIG. 11, and step S21 is a procedure executed by the image photographing apparatus 400 shown in FIG. Steps S22 to S27 are procedures executed by the read processing computer 500 shown in FIG.

  First, in step S21, an image capturing stage is performed in which the image capturing apparatus 400 is used to magnify and capture a region to be captured that forms part of the recording surface of the information recording medium M, and the captured image obtained is captured as image data. Executed. In step S22, the readout processing computer 500 executes a captured image storage stage in which the captured image is stored. In step S23, the readout processing computer 500 performs registration from the captured image stored in the captured image storage stage. By detecting the mark, a bit recording area recognition stage for recognizing each bit recording area Ab is executed.

  In this bit recording area recognition stage, if the bit recording area Ab is successfully recognized, the process proceeds to step S25 through step S24, but if the bit recording area Ab is not recognized, that is, the position at the time of photographing. If there is a deviation and the complete bit recording area Ab is not included in the captured image, the process returns to step S21, and the image capturing stage is executed again. At this time, a process of changing the shooting target area by the image shooting apparatus is performed so that a correct shot image can be obtained.

  In step S25, the unit bit matrix recognition stage in which the reading processing computer 500 recognizes the unit bit matrix B (Ui) based on the pattern in the bit recording area Ab is executed. Such processing is repeatedly executed through step S26 until the recognition of all necessary areas is completed. In other words, the image capturing stage of step S21 is performed while controlling the change of the shooting target area by the image shooting apparatus so that the read processing computer 500 can obtain the shot images of all the bit recording areas Ab to be read. A series of processes from is repeated.

  Finally, in step S27, the read processing computer 500 generates unit data Ui from the individual unit bit matrix B (Ui) recognized in the unit bit matrix recognition stage in step S25, and synthesizes the individual unit data Ui. As a result, a data restoration step for restoring the digital data D to be stored is executed.

<<< §6. Problems with how to interpret data bits >>
Next, a problem relating to a method for interpreting data bits that occurs when information is recorded as a fine physical structure pattern on a medium as in the above-described prior invention will be described. FIG. 2 shows an example in which unit data U1 constituting the first 25 bits of digital data D to be recorded is recorded as a unit bit figure pattern P (U1) arranged in the bit recording area Ab. In the case of the illustrated example, 25-bit information constituting the unit bit matrix B (U1) is represented by the presence or absence of a bit figure at each position constituting the 5-by-5 matrix. In particular, in the case of the example shown here, the bit “1” is indicated when the small black figure F painted black is arranged, and the bit “0” is indicated when it is not arranged.

  As shown in FIG. 1, when drawing data E for drawing such a graphic pattern is generated by the storage processing computer 100, an exposure process by the beam exposure apparatus 200 and a patterning process by the patterning apparatus 300 are executed. An information recording medium M on which digital data D is recorded is created. FIG. 4 shows an example of an exposure process and a patterning process for forming a pattern corresponding to the second row of the 5-by-5 matrix constituting the unit bit figure pattern P (U1) shown in FIG. It is shown.

  An information recording medium M1 shown in FIG. 4 (e) is a medium obtained through such processing. For each arrangement position of bit information, the concave portion C is a bit “1” and the convex portion V is a bit “0”. In the illustrated example, 5-bit data “10110” can be read. The data corresponds to the information in the second row of the unit bit matrix B (U1) shown in FIG. 2, and the recorded data has been read correctly. On the other hand, when reading the information recording medium M1, if the concave portion C is interpreted as a bit “0” and the convex portion V is interpreted as a bit “1”, 5-bit data “01001” is read in the illustrated example. As a result, correct reading cannot be performed.

  Thus, when reading data, if the interpretation method of each data bit (in this example, which of the concave portion and the convex portion is interpreted as bit “1” or bit “0”) is different, the bit value Therefore, correct bit information intended at the time of recording cannot be read. Of course, since the unit bit figure pattern P (U1) illustrated in FIG. 2 is actually recorded on the information recording medium M as a very fine uneven structure, even if the actual information recording medium M is visually observed, The pattern cannot be grasped with the naked eye (in order to observe the actual pattern, a microscope with a considerably high magnification is required).

  Considering such circumstances, it is preferable to record some information indicating the interpretation method of the data bits together with the information recording medium M itself at the time of data recording. For example, in the case of the above example, if information consisting of a character string such as “the concave portion is bit“ 1 ”” is written in an information recording medium M in a form that can be visually observed when data is recorded, At the time of reading, it becomes possible to interpret the individual data bits in the correct way based on this information. Of course, if the interpretation method always paying attention to the bit “1” is shown, the word “concave” may be simply written in such a manner that it can be visually observed.

  Specifically, an operator who performs an information reading process using the information reading apparatus shown in FIG. 6 first observes the information recording medium M to be read, and says “the recess is bit“ 1 ””. After obtaining the information, the unit bit matrix recognition unit 530 may be set to interpret the recess as the bit “1”. In this case, the unit bit matrix recognizing unit 530 recognizes the unevenness of each lattice point position from the photographed image, and if the concave portion, the bit “1” is recorded, and if the convex portion, the bit “0” is recorded. The data bits can be recognized. Of course, when the information that “the convex part is bit“ 1 ”” is recorded on the information recording medium M, the reverse setting is made to the unit bit matrix recognition unit 530. If it is “1”, and if it is a recess, the recognition that the bit “0” is recorded may be performed.

  However, as a method of recording the data bit interpretation method on the medium itself, as in the above example, a method of simply recording information such as “the concave portion is bit“ 1 ”” on the medium as it is is practical. , Not very preferable. The reason will be described below.

  The first reason is that when a medium is copied by a physical method, it cannot be handled correctly. At present, information recording media such as CDs and DVDs that record music and videos are distributed on the market as commercial mass-produced products. These mass-produced media are usually manufactured through a physical replication process based on the original plate. In a duplicate produced by such a duplication process, the concavo-convex structure of the original plate is reversed.

  FIG. 13 is a side cross-sectional view showing a general duplication method of an information recording medium having a concavo-convex structure formed on the surface. An information recording medium M1 and a duplication creation medium M0 are prepared as original plates. A process is shown in which the uneven structure formed on the surface of the medium M1 is transferred to the surface of the medium M0 by pressing the medium M0. FIG. 14 is a side sectional view showing a state in which a duplicate is created by the duplication method shown in FIG. That is, the replica creation medium M0 shown in FIG. 13 is changed to the medium M2 (replicated material) shown in FIG. Since the concavo-convex structure formed on the upper surface of the original information recording medium M1 is transferred to the lower surface of the duplicated information recording medium M2, the concavo-convex relationship is reversed.

  Therefore, the correct interpretation method of the data bits for the information recording medium M2 shown in FIG. 14 is a reverse of the interpretation method of the data bits for the original information recording medium M1. Specifically, as shown in the figure, in the case of the medium M1, the concave portion should be interpreted as the bit “1” and the convex portion as “0”, whereas in the case of the medium M2, the convex portion is represented as the bit “1”. It is necessary to interpret the recess as “0”. In this way, taking into account that the interpretation method of the data bits is reversed due to the duplication process, at the time of recording, information indicating a unique interpretation method such as “the convex part is bit“ 1 ”” should be recorded together. Is not preferred.

  As described above, a method of recording an identification mark having an asymmetrical shape has been known for a long time as a method for alerting the operator when so-called “pattern inversion (inversion)” occurs. For example, when a printed material is generated by an optical process using a transparent document sheet, if the document sheet is set upside down, an inverted image is also formed on the printed material. In order to prevent such a mistake, an identification mark having an asymmetric shape may be recorded on the original sheet. For example, if a large letter “F” is recorded as an identification mark, when the original sheet is set upside down, the letter “F” becomes a reverse letter (mirror image letter). You can easily recognize that you have done this.

  Therefore, even in the above-described prior application, if a method of recording an identification mark having an asymmetric shape is adopted, even if the concavo-convex structure of the original plate is reversed by the duplication process, the concavo-convex shape is given to the person who performs the reading operation. It can be evoked that reversal has occurred.

  FIG. 15 is a plan view showing the relationship between the original M1 and its duplicate M2 when a method of recording a large “F” as an identification mark is used (hatching is for indicating an area). is there). FIG. 15A is a plan view of the information recording medium M1 serving as the original plate (a diagram showing the concavo-convex structure surface). The main recording area Aα shown by hatching and the sub-recording area Aβ arranged in the upper left corner are shown. Is shown.

  Here, the main recording area Aα is an area for recording information of individual data bits constituting digital data to be recorded. Specifically, a large number of unit recording areas Au shown in FIG. 2 are arranged. This is the recorded area. In the case of the original information recording medium M1, the convex portion V indicates the bit “0” and the concave portion C indicates the bit “1”. On the other hand, the sub-recording area Aβ is an area for recording the identification mark m1 having an asymmetric shape. In the example shown in the drawing, a large “F” character that can be observed with the naked eye is recorded as the identification mark m1.

  On the other hand, FIG. 15B is a plan view of the information recording medium M2 replicated by performing the pressing process shown in FIG. 13 using the information recording medium M1 shown in FIG. Figure). In other words, FIG. 15 (a) is a top view of the medium M1 shown in FIG. 14, whereas FIG. 15 (b) is a bottom view of the medium M2 shown in FIG. Therefore, the sub recording area Aβ arranged in the upper left corner in the plan view of FIG. 15A is arranged in the upper right corner in the plan view of FIG. 15B, and “F” in FIG. In FIG. 15B, the identification mark m1 indicating the letter "" is changed to the identification mark m2 indicating the reverse letter of "F".

  In the medium M2 (replica) shown in FIG. 15 (b), since the concavo-convex structure is reversed with respect to the medium M1 (original) shown in FIG. 15 (a), the convex portion V indicates the bit “1” and the concave portion C indicates bit “0”. Therefore, when reading the digital data recorded in the main recording area Aα, when reading from the original information recording medium M1, the convex portion V is set to bit “0” and the concave portion C is set to bit “1”. In the case of reading from the interpreted information recording medium M2, it is necessary to interpret the convex portion V as a bit “1” and the concave portion C as a bit “0”. Of course, when grandchild duplication is performed using the medium M2 shown in FIG. 15B, the obtained grandchild duplicated version needs to be interpreted in the same way as the original version M1.

  As described above, even when the number of generations of duplication is repeated, it is possible to recognize which interpretation should be adopted for each data bit of the plate by the identification mark m1 or m2 recorded in the sub-recording area Aβ. It is. That is, if the identification mark m1 indicating the positive character “F” is recorded, the concave portion C is interpreted as a bit “1”, and if the identification mark m2 indicating the reverse character of “F” is recorded, the concave portion It is sufficient to interpret C as bit “0”. Of course, as the identification mark, a character string such as “the recess is bit“ 1 ”” may be used. In this case, if the character string “The concave part is bit“ 1 ”” is described in a positive character, the concave part should be interpreted as the bit “1” literally, and the character string should be a reverse letter. On the contrary, the concavity may be interpreted as a bit “0”.

  In this way, even when the medium is duplicated by a physical pressing process and the uneven structure of the original plate is assumed to be reversed, a method of recording an identification mark having an asymmetric shape in the sub-recording area Aβ. If it is adopted, it is possible to transmit the correct interpretation method of the data bits to the operator who performs the reading operation.

  However, as in the prior invention, when recording information as a fine physical structure pattern by performing beam exposure and patterning processing on the substrate, in the method of recording an identification mark having an asymmetric shape, There may be cases where the correct interpretation of the data bits cannot always be conveyed. This is due to the following second reason.

  The second reason why it is not preferable to simply record the data bit on the medium as an interpretation method such as “the concave portion is bit“ 1 ”” is that beam exposure and patterning processing are performed using the same graphic pattern. Even in such a case, the physical structure actually formed on the substrate differs depending on the beam exposure and patterning method employed.

  For example, in the case of the beam exposure and patterning process illustrated in FIG. 4, the inside of a small black square (bit graphic F indicating bit “1”) constituting the unit bit graphic pattern P (U1) shown in FIG. 2 is exposed. In addition, a positive resist is used as the resist layer 20. As a result, in the information recording medium M1 shown in FIG. 4 (e), the bit “1” is expressed as the concave portion C and the bit “0” is expressed as the convex portion V. However, when the outside of a small black square is exposed or a negative resist is used as the resist layer 20, the data bit interpretation of the concave portion C and the convex portion V on the generated information recording medium is changed. come.

  FIG. 16 is a side sectional view showing another specific process different from the exposure step and the patterning step shown in FIG. 4 (only the cut surface is shown and the illustration of the structure behind is omitted). That is, in the process shown in FIG. 16, the inside of the bit figure F indicating the bit “1” is exposed, but a negative resist is used as the resist layer 20. Therefore, the exposure process shown in FIG. 16B does not change the point that the exposure part 21 and the non-exposure part 22 are generated. However, when the development process is performed, the non-exposure part 22 is dissolved in the developer, and FIG. As shown in c), the exposed portion 21 remains as the remaining portion 24.

  Subsequently, when etching is performed, as shown in FIG. 16 (d), the portion of the upper surface of the molding target layer 10 covered with the remaining portion 24 serving as a mask is not corroded but exposed. The part which has been corroded receives a recess. In this way, the molding target layer 10 is processed into the molding target layer 13 having the concavo-convex structure formed on the upper surface. The molded layer 13 thus obtained becomes an information recording medium M3 as shown in FIG. 16 (e) by removing the remaining portion 24.

  Here, when the information recording medium M1 shown in FIG. 4 (e) and the information recording medium M3 shown in FIG. 16 (e) are compared, both are media on which the same data bit “10110” is recorded. In the former, the concave portion indicates the bit “1” and the convex portion indicates the bit “0”, whereas in the latter, the convex portion indicates the bit “1” and the concave portion indicates the bit “0”. The interpretation of is completely reversed.

  As described above, an example in which the data bit interpretation method for the concavo-convex structure formed on the medium is reversed due to the difference between using a positive resist or a negative resist as the resist layer 20 in the patterning process. As described above, when performing the beam exposure process, the data bit interpretation method for the concavo-convex structure formed on the medium is reversed depending on whether the inside of the bit figure F is exposed or the outside is exposed. It will be.

  This is because, in the information storage apparatus shown in FIG. 1, even when the information recording medium M is created using exactly the same drawing data E, the beam exposure processing conditions in the beam exposure apparatus 200 and the patterning apparatus 300 This means that there is a difference in the interpretation method of the data bits expressed by the concavo-convex structure formed on the finally obtained information recording medium M depending on the patterning process conditions.

  Accordingly, as illustrated in FIG. 15A, drawing data E for recording the identification mark m1 having an asymmetric shape such as the letter “F” is prepared in the sub-recording area Aβ. Even if the information recording medium M is created based on the drawing data E, it is not possible to recognize the correct data bit interpretation method using the identification mark at the time of reading. That is, as long as the same drawing data E is used, the sub-recording area is created both in the process shown in FIG. 4 (using positive resist) and in the process shown in FIG. 16 (using negative resist). The identification mark m1 in Aβ is the positive character “F”.

  That is, when created by the process shown in FIG. 4, a medium M1 as shown in FIG. 15 (a) is obtained, and when created by the process shown in FIG. 16, a medium M3 as shown in the plan view of FIG. can get. The identification mark m1 in the former sub-recording area Aβ is a positive character “F”, and the identification mark m3 in the latter sub-recording area Aβ is also a positive character “F”, and the identification mark remains unchanged. However, in the former case, the convex portion V indicates the bit “0” and the concave portion C indicates the bit “1”, whereas in the latter case, the convex portion V indicates the bit “1” and the concave portion C indicates the bit “0”. Show.

  On the other hand, FIG. 17 (b) is a plan view of a medium M4 replicated by a pressing process using the medium M3 shown in FIG. 17 (a) as an original plate. Here, although the identification mark m4 in the sub-recording area Aβ is a reverse letter of “F”, the convex portion V indicates the bit “0” and the concave portion C indicates the bit “1”. Eventually, the medium M1 shown in FIG. 15 (a) and the medium M4 shown in the medium 17 (b) have the opposite relationship between the normal character and the reverse character as the presented identification marks, but the data bit interpretation method Is common in that the convex portion V should be interpreted as a bit “0” and the concave portion C as a bit “1”. Similarly, the medium M2 shown in FIG. 15 (b) and the medium M3 shown in the medium 17 (a) have the opposite relationship between the back letter and the normal letter as the identification marks presented, but the interpretation of the data bits The method is common in that the convex portion V should be interpreted as a bit “1” and the concave portion C as a bit “0”.

  As described above, when information is recorded as a fine physical structure pattern by performing beam exposure and patterning processing on the substrate, the method of recording an identification mark having an asymmetrical shape corrects the data bit. The interpretation method cannot be communicated. In order to cope with such a problem, the present invention proposes a new technique for recording information indicating a data bit interpretation method. Hereinafter, the new method will be described in detail in Section 7 and later. For convenience of explanation, an embodiment in which the new technique is applied to the prior application invention will be described here, but the present invention is not limited to the application to the information storage method according to the prior application invention, and is applied to the substrate. On the other hand, this technique is widely applicable to information storage methods for recording information as a fine physical structure pattern by performing beam exposure and patterning processing.

<<< §7. Basic embodiment of information storage apparatus according to the present invention >>
FIG. 18 is a block diagram showing a basic configuration of an information storage device according to a basic embodiment of the present invention. The information storage device shown in FIG. 18 is a device including a storage processing computer 100 ′, a beam exposure device 200, and a patterning device 300, as in the device shown in FIG. 1, and stores digital data D to be stored as information. It has a function of writing and storing in the recording medium M. Here, the beam exposure apparatus 200 and the patterning apparatus 300 are the same constituent elements as the apparatuses having the same reference numerals shown in FIG.

  On the other hand, the storage processing computer 100 ′ of the information storage apparatus shown in FIG. 18 includes a data input unit 110, a main information pattern generation unit 170, a sub information pattern generation unit 180, and a drawing data generation unit 160 ′. Here, the data input unit 110 is the same component as the data input unit 110 shown in FIG. 1 and plays a role of inputting the digital data D to be stored.

  The main information pattern generation unit 170 shown in FIG. 18 generates a main information pattern Pα indicating information of individual data bits constituting the input digital data D, and the sub information pattern generation unit 180 uses the main information pattern Pα. A sub information pattern Pβ indicating how to interpret the indicated data bit is generated. Then, the drawing data generation unit 160 ′ generates drawing data E for drawing the main information pattern Pα and the sub information pattern Pβ.

  As shown in the figure, the main information pattern generation unit 170 includes a unit data generation unit 120, a unit bit matrix generation unit 130, a unit bit graphic pattern generation unit 140, and a unit recording graphic pattern generation unit 150. Each component is the same as each component indicated by the same reference numeral in FIG. Therefore, the main information pattern Pα generated by the main information pattern generation unit 170 is, for example, an aggregate of unit recording graphic patterns R (U1) as illustrated in FIG.

  On the other hand, the sub information pattern Pβ generated by the sub information pattern generation unit 180 is a pattern indicating a method of interpreting the data bits indicated by the main information pattern Pα, and is identified in FIGS. 15 (a) and 17 (a). It performs the same function as the marks m1 and m3. However, as will be described later, the sub information pattern Pβ used in the present invention is not a single identification mark but a pair of identification marks.

  The drawing data generation unit 160 ′ defines a main recording area Aα and a sub recording area Aβ on the drawing target surface, and arranges the main information pattern Pα generated by the main information pattern generation unit 170 in the main recording area Aα. A composite pattern is generated by arranging the sub information pattern Pβ generated by the sub information pattern generation unit 180 in the recording area Aβ, and drawing data E for drawing the composite pattern is generated.

  Based on the drawing data E generated in this way, the beam exposure apparatus 200 performs beam exposure using an electron beam or a laser beam on the substrate S as an information recording medium, and has a development processing unit 310 and an etching processing unit 320. The point that the patterning device 300 generates the information recording medium M on which the physical structure pattern corresponding to the drawing data E is formed by performing the patterning process on the exposed substrate S is the information shown in FIG. The same as the storage device.

  That is, the beam exposure apparatus 200 performs beam exposure on the surface of the resist layer on a substrate having a layer to be molded and a resist layer covering the layer, and the development processing unit 310 performs exposure or non-exposure of the resist layer. The substrate is impregnated with a developer having a property of dissolving the part and a part thereof is left as a remaining part, and the etching processing part 320 performs etching on the layer to be molded using the remaining part of the resist layer as a mask. At this time, the beam exposure apparatus 200 may expose the inside of the bit figure F or the outside. Further, as the resist layer, a positive resist or a negative resist may be used.

  After all, the difference between the information storage device according to the invention of the prior application shown in FIG. 1 and the information storage device according to the present invention shown in FIG. 18 is that the former storage processing computer 100 draws the main information pattern Pα. Whereas the data E is generated, the latter storage processing computer 100 ′ generates drawing data E for drawing a composite pattern in which the sub information pattern Pβ is added to the main information pattern Pα. .

  Of course, the sub-information pattern generation unit 180 newly added in the latter is actually a component constructed by incorporating a program into the computer, and is a component of the storage processing computer 100 ′ shown in FIG. A data input unit 110, a main information pattern generation unit 170, a sub information pattern generation unit 180, and a drawing data generation unit 160 ′ can be configured by incorporating a dedicated application program in a general-purpose computer.

  Next, the sub information pattern Pβ generated by the sub information pattern generation unit 180 will be described. Here, first, the information recording medium M5 created by executing the process shown in FIG. 4 (process using a positive resist as the resist layer 20) by the patterning device 300 in the information storage device shown in FIG. 19 shows an information recording medium M6 produced by executing the process shown in FIG. 16 (process using a negative resist as the resist layer 20) (shown by hatching). Is for indicating the area).

  In both the medium M5 shown in FIG. 19 and the medium M6 shown in FIG. 20, a main recording area Aα shown by hatching in the figure and a sub recording area Aβ arranged at the upper left corner of the figure are provided on the upper surface. ing. Here, the main recording area Aα is an area in which a main information pattern Pα indicating information of individual data bits constituting the digital data D to be stored is recorded. For example, unit recording as illustrated in FIG. This is an area in which a collection of graphic patterns R (Ui) (i = 1, 2, 3,...) Is recorded. On the other hand, the sub-recording area Aβ is an area in which a sub-information pattern Pβ indicating how to interpret each data bit recorded as the main information pattern Pα is recorded. An area Aβ1 and a second sub-recording area Aβ2 are included.

  As described above, the medium M5 shown in FIG. 19 is created by executing the process shown in FIG. 4, and the main information pattern Pα recorded in the main recording area Aα has the bit “0” by the convex portion V. The concave-convex structure expresses “1” and the bit “1” by the concave portion C. On the other hand, the medium M6 shown in FIG. 20 is created by executing the process shown in FIG. 16, and the main information pattern Pα recorded in the main recording area Aα is a bit " The concave-convex structure expresses “1” and the bit “0” by the concave portion C.

  As described above, the medium M5 shown in FIG. 19 and the medium M6 shown in FIG. 20 are both media created based on the same main information pattern Pα. Since a type resist is used and on the other hand, a negative type resist is used, this results in a difference in the interpretation method of the data bits. The sub information pattern Pβ recorded in the sub recording area Aβ always plays a role of indicating a correct interpretation method even when such a difference in interpretation method occurs.

  In the illustrated example, the sub information pattern Pβ recorded in the sub recording area Aβ is recorded in the first identification mark m10 recorded in the first sub recording area Aβ1 and the second sub recording area Aβ2. And a second identification mark m20. Specifically, the first identification mark m10 is constituted by a closed region showing a character “convex”, and the second identification mark m20 is constituted by a closed region showing a character “concave”. From the point of view of whether the identification mark looks brighter, it functions as a mark indicating the correct interpretation method of the data bits.

  Here, for the sake of convenience, hatching by meshes and hatching by dots are performed in the closed regions constituting the two identification marks m10 and m20 in the figure, and the hatching region by meshes is observed brighter than the hatching region by dots. Shall be. Accordingly, in the case of the medium M5 shown in FIG. 19, the second identification mark m20 indicating the “concave” character appears brighter than the first identification mark m10 indicating the “convex” character. In the case of the medium M6 shown in FIG. 5, the first identification mark m10 indicating the “convex” character appears brighter than the second identification mark m20 indicating the “concave” character (the reason for this is Later).

  In addition, in the example shown here, when the character “concave” appears bright, the concave portion C is set to bit “1”, and when the character “convex” appears bright, the convex portion V is set to the bit. An interpretation method of “1” is shown. Accordingly, since the reading operator who has the medium M5 shown in FIG. 19 looks brighter on the character “concave”, when reading out the individual data bits recorded in the main recording area Aα, It can be recognized that an interpretation method of bit “1” should be adopted, and the reading operator who has the medium M6 shown in FIG. 20 records the “convex” character in the main recording area Aα because it looks brighter. It can be recognized that an interpretation method in which the convex portion V is the bit “1” should be adopted when reading the individual data bits.

  Further, when a duplicate is created by the pressing process described above, the uneven structure of the duplicate created using the medium M5 shown in FIG. 19 as the original plate is equivalent to the medium M6 shown in FIG. 20, and the medium M6 shown in FIG. 19 is equivalent to the medium M5 shown in FIG. 19, the information recording medium created by the information storage device according to the present invention also has “convex” and “concave” for the duplicate. It is possible to recognize the correct method for interpreting data bits based on the judgment of which of the characters appears brighter.

<<< §8. Physical structure of a pair of identification marks >>
Next, the physical structure of the first identification mark m10 and the second identification mark m20 will be described. The pair of identification marks m10 and m20 recorded in the sub-recording area Aβ needs to play a role of presenting a correct data bit interpretation method to the reading operator by the method described above. Therefore, it has a structure closely related to the data bits recorded in the main recording area Aα. First, let us consider the characteristics of data bits recorded in the main recording area Aα.

  As described above, the main information pattern Pα generated by the main information pattern generation unit 170 is recorded in the main recording area Aα. The main information pattern Pα is, for example, an aggregate (i = 1, 2, 3,...) Of unit recording graphic patterns R (Ui) as illustrated in FIG. Here, considering the entity of the unit recording graphic pattern R (Ui), it can be seen that the pattern has a mixture of areas having two kinds of attributes.

  Specifically, in the example shown in FIG. 2, the unit recording graphic pattern R (U1) is a pattern in which a “black region” and a “white region” are mixed in the unit recording region Au. Of course, actually, the unit recording graphic pattern R (U1) is expressed by vector data indicating the contours of the bit graphic F and the alignment marks Q1 to Q4, as in the example shown in FIG. The inside becomes a “black area” and the outside becomes a “white area”.

  The main information pattern generation unit 170 shown in FIG. 18 generates a pattern in which areas having two types of attributes of “black area” and “white area” are mixed as the main information pattern Pα to be recorded in the main recording area Aα. Will do. The beam exposure apparatus 200 performs a beam exposure process on one of the areas having the two types of attributes, and the patterning apparatus 300 performs a patterning process on the substrate after exposure. It will be.

  FIG. 4 shows an example in which a beam exposure process is performed on the “black region” and a patterning process using a positive resist as the resist layer 20 is performed. As a result, as shown in FIG. 4E, an information recording medium M1 in which the convex portion V represents the bit “0” and the concave portion C represents the bit “1” is obtained. On the other hand, if the beam exposure process is performed on the “white region” and the patterning process using a positive resist is performed as the resist layer 20, the convex portion V has the bit “1” and the concave portion C has the bit “0”. Is obtained (equivalent to the information recording medium M3 shown in FIG. 16 (e)).

  Similarly, FIG. 16 shows an example in which a beam exposure process is performed on the “black region” and a patterning process using a negative resist as the resist layer 20 is performed. As a result, as shown in FIG. 16E, an information recording medium M3 in which the convex portion V represents the bit “1” and the concave portion C represents the bit “0” is obtained. On the other hand, if beam exposure processing is performed on the “white region” and patterning processing is performed using a negative resist as the resist layer 20, the convex portion V has the bit “0” and the concave portion C has the bit “1”. Is obtained (equivalent to the information recording medium M1 shown in FIG. 4 (e)).

  As a general rule, if one of the above-described “black region” and “white region” is called a “first attribute main region” and the other is called a “second attribute main region”, the main information pattern Pα is A predetermined point (in the example shown in FIG. 3, each lattice point L) that is configured by the first attribute main area and the second attribute main area and corresponds to each data bit is included in the first attribute main area. Depending on whether it exists or in the second attribute main area, this pattern represents binary information of individual data bits.

  In the case of the embodiment described here, the main information pattern generation unit 170 selects one of the individual bits “1” and the individual bits “0” constituting the digital data D to be stored (example in FIG. 2). The bit "1") is converted into individual bit graphics F composed of closed areas, and the main information pattern in which the internal area of the bit graphic F is the first attribute main area and the external area is the second attribute main area Pα will be generated. The main information pattern Pα is recorded in the main recording area Aα shown in FIGS. 19 and 20 as described above.

  On the other hand, the sub information pattern Pβ generated by the sub information pattern generation unit 180 has a pair of identification marks m10 and m20 recorded in the sub recording area Aβ, as shown in FIGS. Here, the identification mark m10 is a mark composed of “convex” characters arranged in the first sub-recording area Aβ1, and an interpretation method of “the convex portion is bit“ 1 ”” (naturally, the concave portion is a bit. This is a mark for presenting “0”. The identification mark m20 is a mark composed of “concave” characters arranged in the second sub-recording area Aβ2, and an interpretation method of “concave portion is bit“ 1 ”” (naturally convex portion is bit ” This is a mark for presenting “0”.

  As described above, the reading operator grasps the interpretation method indicated by the brighter mark of the pair of identification marks m10 and m20 as a correct data bit interpretation method.

  Next, the substance of the pair of identification marks m10 and m20 will be described with reference to FIG. FIG. 21 is a plan view showing an example of the drawing pattern P (E) created by the information storage device shown in FIG. Here, the drawing pattern P (E) is obtained by synthesizing the main information pattern Pα generated by the main information pattern generation unit 170 and the sub information pattern Pβ generated by the sub information pattern generation unit 180. Is a composite pattern. The drawing data generation unit 160 ′ generates the drawing pattern P (E) by combining the main information pattern Pα and the sub information pattern Pβ, and then uses the drawing data used to draw the drawing pattern P (E). A process of generating E is performed.

  As described above, the main information pattern Pα to be recorded in the main recording area Aα is a pattern in which areas having two types of attributes “black area” and “white area” are mixed. Similarly, the sub-information pattern Pβ to be recorded is a pattern in which areas having two types of attributes “black area” and “white area” are mixed.

  The lower part of FIG. 21 shows an enlarged view (image in a circle) of each partial region of the drawing pattern P (E) shown in the upper part of FIG. That is, the image in the lower circle p1 is an enlarged view of the partial area p1 in the first identification mark m10 arranged in the first sub-recording area Aβ1 shown in the upper stage, and the image in the lower circle p2 is It is an enlarged view of the partial area p2 in the second identification mark m20 arranged in the second sub-recording area Aβ2 shown in the upper stage, and the image in the lower circle p3 is a partial area in the main recording area Aα shown in the upper stage It is an enlarged view of p3. For convenience of illustration, the dimensional ratio of each part in FIG. 21 is set ignoring the actual dimensional ratio. For example, the partial areas p1 to p3 indicated by small circles in the upper stage are actually the naked eyes. Then, the area becomes so small that it cannot be observed.

  The enlarged image of the partial area p3 shown in the lower part of FIG. 21 shows a pattern constituting one unit recording area Au, and a “black area” (first attribute) showing the inside of each bit figure and the alignment mark. The main area G1) and a “white area” (second attribute main area G2) indicating an external background portion (the broken line and the alternate long and short dash line in the figure are auxiliary lines for indicating the arrangement, and the actual pattern Is not the line that makes up.) As described above, the main information pattern Pα to be recorded in the main recording area Aα is a mixed pattern of areas having two types of attributes “black area” and “white area”. .

  On the other hand, as can be seen from the enlarged images of the partial areas p1 and p2 shown in the lower part of FIG. 21, the sub information pattern Pβ to be recorded in the sub recording area Aβ is also “black area” (first attribute sub area g1). This is a mixed pattern of areas having two types of attributes called “white areas” (second attribute subarea g2). However, since the main information pattern Pα is a pattern showing individual bit figures and alignment marks, the sub information pattern Pβ is a pattern showing a pair of identification marks m10 and m20. Is different.

  That is, the pattern in the closed region constituting the identification marks m10 and m20 forms a striped pattern of “black region” and “white region” as shown in the enlarged images of the partial regions p1 and p2. . This is because a diffraction grating for visible light is formed inside the identification marks m10 and m20 when recorded as a concavo-convex structure on the medium M. As a result, a pattern in which elongated strip-like “black regions” and elongated strip-like “white regions” are alternately arranged is formed in the closed regions constituting the identification marks m10 and m20.

  Each grating line forming this diffraction grating is set to be in a direction parallel to the common arrangement axis Z. The illustrated example is an example in which the arrangement axis Z is set as an axis extending in the vertical direction in the drawing, and therefore, stripe patterns extending in the vertical direction are formed in the partial regions p1 and p2. Of course, the orientation of the arrangement axis Z may be set in an arbitrary direction.

  The important point here is that when the stripe pattern in the partial region p1 and the stripe pattern in the partial region p2 are compared, the width W1 of the band constituting the “black region” (first attribute subregion g1) and “ The size relationship with the width W2 of the band constituting the “white region” (second attribute subregion g2) is reversed between the two. Specifically, in the illustrated example, W1> W2 for the partial region p1 in the identification mark m10, whereas W1 <W2 for the partial region p2 in the identification mark m20. . This difference in width produces a difference in brightness during observation, the details of which will be described later.

  In the figure, only the patterns in the partial areas p1 and p2 surrounded by circles are drawn. Of course, the partial areas p1 and p1 are formed over the entire inner closed area of the “convex” character constituting the identification mark m10. A similar pattern is formed, and the same pattern as that of the partial region p2 is formed over the entire inner closed region of the “concave” character constituting the identification mark m20. In other words, the inside of the “convex” character and the inside of the “concave” character are filled with a striped pattern extending in the vertical direction of the figure.

  In the case of the embodiment shown here, the background portion (region outside the “convex” character) in the first sub-recording area Aβ1 and the background portion (region outside the “concave” character) in the second sub-recording region Aβ2. ) Is configured as a “white region” (second attribute subregion g2), but the background portion may be configured as a “black region” (first attribute subregion g1).

  Alternatively, a striped pattern (a pattern that functions as a diffraction grating on the medium) including “black areas” and “white areas” may be formed in these background portions. However, since it is necessary to make it possible to recognize the outline of the “convex” character and the outline of the “concave” character when the reading operator observes it, the background portion also has a striped pattern (diffraction grating). When forming the pattern, it is necessary to change the direction or pitch of the stripe pattern (diffraction grating) inside the identification mark so that the outline of the identification mark can be recognized during observation. Therefore, in practice, it is preferable to set the background portion as a “white area” or a “black area”.

  Eventually, a pattern in which a “black area” and a “white area” are mixed is arranged in both the main recording area Aα and the sub recording area Aβ, and the drawing pattern P (E) is This is an aggregate of a large number of closed regions belonging to either of these two types. Generally speaking, the main information pattern Pα arranged in the main recording area Aα is a mixture of the first attribute main area G1 (for example, “black area”) and the second attribute main area G2 (for example, “white area”). The sub information pattern Pβ arranged in the sub recording area Aβ is a mixed pattern of the first attribute subarea g1 (for example, “black area”) and the second attribute subarea g2 (for example, “white area”). It will be.

  Here, if the “first attribute” area is an area where beam exposure is performed and the “second attribute” area is an area where beam exposure is not performed, in the above example, the “black area” is exposed. In other words, the “white area” is not exposed. In other words, in this case, the drawing data generation unit 160 ′ performs exposure on the first attribute main region G1 and the first attribute subregion g1, and the second attribute main region G2 and the second attribute subregion g2. In this case, drawing data E for generating no exposure is generated. Of course, conversely, the “second attribute” region may be a region where beam exposure is performed, and the “first attribute” region may be a region where beam exposure is not performed.

  As described above, the “first attribute” depends on which attribute region is subjected to beam exposure at the time of the beam exposure process or depending on whether a positive type or a negative type resist is used at the time of the patterning process. Is the convex portion V or the concave portion C on the medium M (in other words, whether the “second attribute” region is the concave portion C or the convex portion V on the medium M). Will change.

  However, the important point here is that if the first attribute main region G1 becomes the convex portion V on the final medium M, the first attribute subregion g1 also becomes the convex portion V, and the first attribute main region G1. Is a recess C, the first attribute subregion g1 is also a recess C. Of course, if the second attribute main region G2 becomes the convex portion V, the second attribute subregion g2 also becomes the convex portion V, and if the second attribute main region G2 becomes the concave portion C, the second attribute subregion g2 also becomes the concave portion. C. This is a universal that does not change regardless of which attribute region is subjected to beam exposure at the time of beam exposure processing, and whether positive or negative resist is used at the time of patterning processing. It is a matter.

  Therefore, in the medium M created based on the drawing pattern P (E) shown in FIG. 21 and the duplicate created by the pressing process using the medium M as an original, it is shown in each of the partial areas p1 to p3. Whether all “black areas” become convex V and all “white areas” become concave C (such a medium is called “black convex medium” for convenience), or all “black areas” are concave C, and all “white areas” become convex portions V (such a medium is called “black concave medium” for convenience). Specifically, the medium M1 shown in FIG. 4 (e) is called “black concave medium”, the medium M2 shown in FIG. 14 is called “black convex medium”, and the medium M3 shown in FIG. 16 (e) is called “black convex medium”. It will be.

  In the case of this embodiment, the drawing pattern P (E) expresses the bit “1” as a bit figure F composed of “black areas”. The interpretation method that “the convex portion is bit“ 1 ”” may be employed, and when the “black concave medium” is read, the interpretation method that “the concave portion is bit“ 1 ”” may be employed. Therefore, the reading operator only needs to recognize whether the target medium is a “black convex medium” or a “black concave medium”. As described above, the recognition can be performed based on the criterion “which of the pair of identification marks looks brighter”.

  For example, in the case of the example shown in FIG. 21, the first identification mark m10 made of a “convex” character and the second identification mark m20 made of a “concave” character are compared and observed. If the medium appears bright, the medium should be judged as a “black convex medium” and an interpretation method of “the convex part is bit“ 1 ”” should be adopted. If the “concave” character appears brighter The medium may be determined as a “black concave medium” and an interpretation method that “the concave part is bit“ 1 ”” may be employed. Hereinafter, the reason why it is possible to determine whether the medium is the “black convex medium” or the “black concave medium” by comparing the brightness will be described.

  FIG. 22 is a diagram showing the concavo-convex structure of the medium M5 (“black concave medium” shown in FIG. 19) created by executing the process shown in FIG. 4 based on the drawing pattern P (E) shown in FIG. It is. The upper part is a plan view of the drawing pattern P (E) shown in FIG. 21, and the lower part is an enlarged side sectional view of each part of the medium M5 corresponding to each partial area p1 to p3.

  The side sectional view of the partial regions p1 and p2 shown in the lower part of FIG. 22 has a “black region” (first attribute subregion g1) in the enlarged image of the partial regions p1 and p2 shown in the lower part of FIG. 22 shows a concave-convex structure of the medium M5 having the “region” (second attribute sub-region g2) as a convex portion, and a side sectional view of the partial region p3 shown in the lower part of FIG. Regarding the position of the second row in the bit array of 5 rows and 5 columns in the enlarged image, the “black region” (first attribute main region G1) is defined as a recess, and the “white region” (second attribute main region G2) is defined. The concavo-convex structure of the medium M5 as a convex portion is shown. At the time of reading, the data bits recorded in the partial area p3 need to be interpreted as “concave portion is bit“ 1 ”” and “convex portion is bit“ 0 ””.

  On the other hand, FIG. 23 shows the concavo-convex structure of the medium M6 (“black convex medium” shown in FIG. 20) created by executing the process shown in FIG. 16 based on the drawing pattern P (E) shown in FIG. FIG. The upper part is a plan view of the drawing pattern P (E) shown in FIG. 21, and the lower part is an enlarged side sectional view of each part of the medium M6 corresponding to each partial area p1 to p3.

  In the side sectional view of the partial areas p1 and p2 shown in the lower part of FIG. 23, the “black area” (first attribute sub-region g1) in the enlarged image of the partial areas p1 and p2 shown in the lower part of FIG. 23 shows a concave-convex structure of the medium M6 in which the “white region” (second attribute subregion g2) is a concave portion, and the side sectional view of the partial region p3 shown in the lower part of FIG. Regarding the position of the second row in the 5 × 5 bit array in the enlarged image, the “black region” (first attribute main region G1) is a convex portion, and the “white region” (second attribute main region G2) 3 shows a concavo-convex structure of the medium M6 having a concave portion. The data bits recorded in the partial area p3 need to be interpreted as “convex portion bit“ 1 ”” and “concave portion bit“ 0 ”” at the time of reading.

  Next, consider which of the black and concave media M5 shown in FIGS. 19 and 22 is brighter when the pair of identification marks m10 and m20 is comparatively observed. 24A to 24C are enlarged side sectional views of the concavo-convex structure of the partial regions p1 to p3 of the black concave medium M5 shown in the lower part of FIG. Here, let us follow the behavior after reflection of the illumination light when the illumination light is irradiated on the upper surface of the black concave medium M5 obliquely from the upper left direction.

  First, as shown in FIG. 24A, consider the partial region p1 (that is, the internal region of the first identification mark m10). In the figure, the illumination light L1 irradiated to the “black region” (first attribute subregion g1) which is a concave portion and the “white region” (second attribute subregion g2) which is a convex portion are irradiated. An example of the behavior after reflection of the illuminated illumination light L2 is drawn with a one-dot chain line. That is, the illumination light L1 incident on the concave portion collides with the side surface of the convex portion after reflection, whereas the illumination light L2 incident on the convex portion is directed upward as it is after reflection.

  Of course, even if the illumination light is incident on the concave portion, there is also a light that goes upward as it is after reflection, but generally, the probability that the illumination light incident on the concave portion is observed from above is low. As shown in FIGS. 4 (d) and 16 (d), a concave portion is formed by etching in a patterning process for forming a concavo-convex structure on the upper surface of the medium. This is because the side surface forms a corroded surface having a rough surface.

  That is, in FIG. 24 (a), the bottom surface of the concave portion where the illumination light L1 is incident and the side surface of the convex portion to which the reflected light is directed are corroded surfaces having a rough surface. Light is extinguished by scattering and the probability of being observed above is low. On the other hand, the upper surface of the convex portion on which the illumination light L2 is incident is not corroded because it is protected by the resist layer. Therefore, there is a high probability that the illumination light L2 is observed above after being reflected by the upper surface of the convex portion.

  Here, in the partial region p1 shown in FIG. 24A, as shown in FIG. 21, the width W1 of the “black region” (first attribute subregion g1) is “white region” (second attribute subregion g2). ) Is larger than the width W2. Therefore, the ratio of the incident light L1 to the concave portion (black region) that has a high probability of not being observed after reflection is higher than the proportion of the incident light L2 to the convex portion (white region) that is highly likely to be observed after the reflection. When it is observed from above, it is observed dark overall.

  On the other hand, in the partial region p2 shown in FIG. 24B, as shown in FIG. 21, the width W1 of the “black region” (first attribute subregion g1) is “white region” (second attribute subregion g2). Is smaller than the width W2. Accordingly, the ratio of the incident light L3 to the convex part (white area) that is more likely to be observed upward after reflection is higher than the ratio of the incident light L4 to the concave part (black area) that is more likely not to be observed upward after reflection. When observed from above, it is observed bright overall.

  Eventually, when the black concave medium M5 shown in FIG. 19 is observed from above, the second identification mark m20 (partial region p2) indicating the letter “concave” is displayed for the reason described with reference to FIGS. 24 (a) and 24 (b). ) Is observed brighter than the first identification mark m10 (partial region p1) indicating a “convex” character. Therefore, the reading operator can recognize that the target medium is a “black concave medium”, and the data bit recorded in the main recording area Aα is shown in FIG. It is possible to perform a correct reading process employing an interpretation method of bit “1”.

  Next, regarding the black convex medium M6 shown in FIGS. 20 and 23, when a pair of identification marks m10 and m20 are comparatively observed, which one appears brighter will be considered. 25 (a) to 25 (c) are enlarged side sectional views of the concavo-convex structure of the partial regions p1 to p3 of the black convex medium M6 shown in the lower part of FIG. Again, let us follow the behavior of the illumination light after reflection when the illumination light is irradiated on the upper surface of the black convex medium M6 obliquely from the upper left direction.

  First, as shown in FIG. 25A, irradiation is performed on the “black region” (first attribute subregion g1) which is a convex portion of the partial region p1 (that is, the inner region of the first identification mark m10). When the reflected illumination light L5 and the illumination light L6 irradiated to the “white region” (second attribute subregion g2) that is a concave portion are considered after reflection, the illumination light L5 is as described above. Since the upper surface of the incident convex portion is not corroded, the illumination light L5 is highly likely to be observed above after being reflected by the upper surface of the convex portion. On the other hand, since the concave portion into which the illumination light L6 is incident is a corroded surface, the illumination light L6 is diffused on the corroded surface and the probability of being observed above is low.

  Here, in the partial region p1 shown in FIG. 25A, as shown in FIG. 21, the width W1 of the “black region” (first attribute subregion g1) is “white region” (second attribute subregion g2). ) Is larger than the width W2. Therefore, the ratio of the incident light L5 to the convex part (black area) having a higher probability of being observed upward after reflection is higher than the ratio of the incident light L6 to the concave part (white area) having a higher probability of not being observed upward after reflection. When observed from above, it is observed bright overall.

  On the other hand, in the partial region p2 shown in FIG. 25B, as shown in FIG. 21, the width W1 of the “black region” (first attribute subregion g1) is “white region” (second attribute subregion g2). Is smaller than the width W2. Therefore, the ratio of the incident light L7 to the concave portion (white region) that is more likely not to be observed upward after reflection is higher than the proportion of the incident light L8 to the convex portion (black region) that has a higher probability of being observed upward after reflection. When observed from above, it is observed dark overall.

  Eventually, when the black convex medium M6 shown in FIG. 20 is observed from above, the first identification mark m10 (partial region p1) indicating the letter “convex” is displayed for the reason described with reference to FIGS. 25 (a) and 25 (b). ) Is observed brighter than the second identification mark m20 (partial region p2) indicating a “concave” character. Therefore, the reading operator can recognize that the target medium is a “black convex medium”, and the data bits recorded in the main recording area Aα are “protrusive” as shown in FIG. Therefore, correct reading processing using an interpretation method of bit “1” can be performed.

  The advantage of the present invention is that if the drawing data E for drawing the drawing pattern P (E) as illustrated in the upper part of FIG. No matter what beam exposure process or patterning process is performed, a correct data bit is always obtained by comparing the brightness of the pair of identification marks m10 and m20 formed on the final medium. The interpretation method (whether the convex portion is interpreted as a bit “1” or the concave portion is interpreted as a bit “1”) can be recognized.

  In other words, the first attribute region (regions g1 and G1) indicated as “black region” in the lower part of FIG. 21 and the second attribute region (regions g2 and G2) indicated as “white region” are Therefore, either one is a convex portion and the other is a concave portion, and whichever is a convex portion and which is a concave portion, correct data can be obtained by comparing the brightness of the pair of identification marks m10 and m20. Recognize how to interpret bits. The same applies not only to a medium created based on the drawing data E but also to a duplicate copied by the pressing process using the medium as an original.

  As described above, the striped concavo-convex structure formed inside the identification marks m10 and m20 on the medium actually constitutes a diffraction grating. Therefore, the light observed by the reading operator is generated by this diffraction grating. This is diffracted light. Accordingly, a reading operator who has the “black concave medium” shown in FIG. 19 and the “black convex medium” shown in FIG. 20 has a “convex” character and a “concave” in the sub-recording area Aβ in the upper left corner. ”Is observed, and it is determined whether the convex portion is interpreted as a bit“ 1 ”or the concave portion is interpreted as a bit“ 1 ”depending on which character appears brighter (is more clearly visible). be able to.

  Of course, when the “convex” and “concave” characters are observed, the absolute brightness of these characters varies depending on the lighting environment and also varies depending on the direction in which the medium is held. However, since the directions of the diffraction gratings formed inside the “convex” character and the “concave” character are in the same direction (the direction parallel to the arrangement axis Z shown in FIG. 21), As long as the “concave” and “concave” characters are compared and observed, the phenomenon that one of them appears bright has universality, and a correct interpretation method of data bits is always presented.

  Thus, according to the present invention, when information is recorded as a fine physical structure pattern by performing beam exposure and patterning processing on the substrate, information indicating how to interpret the data bits is also recorded. It becomes possible to do.

<<< §9. Specific forms and variations of identification marks >>
After all, the characteristics of the identification marks m10 and m20 described in §8 are summarized as follows. First, as shown in the example of FIG. 21, a band-shaped first attribute sub-region g1 extending in a direction parallel to a predetermined arrangement axis Z is included in the closed region constituting the first identification mark m10. The band-shaped second attribute sub-regions g2 are alternately arranged in the direction orthogonal to the arrangement axis Z, and are parallel to the same arrangement axis Z in the closed region constituting the second identification mark m20. The strip-shaped first attribute sub-regions g1 and the strip-shaped second attribute sub-regions g2 extending in a certain direction are alternately arranged in a direction orthogonal to the arrangement axis Z.

  Moreover, for the closed region constituting the first identification mark m10, the width W1 of the first attribute subregion g1 is set to be wider than the width W2 of the second attribute subregion g2, and the second identification mark m20 is set. Is set so that the width W2 of the second attribute subregion g2 is wider than the width W1 of the first attribute subregion g1.

  On the other hand, the main information pattern generation unit 170 generates a main information pattern Pα in which the first attribute main region G1 and the second attribute main region G2 are mixed, as illustrated in the partial region p3 of FIG. The drawing data generation unit 160 ′ performs a process of generating a combined pattern by combining the main information pattern Pα and the sub information pattern Pβ generated in this way and generating drawing data E for drawing the combined pattern. Become.

  At this time, the drawing data generation unit 160 ′ performs exposure for the first attribute main region G1 and the first attribute subregion g1, and performs exposure for the second attribute main region G2 and the second attribute subregion g2. The exposure is performed on the drawing data E for avoiding the image processing, or the second attribute main region G2 and the second attribute subregion g2, and the first attribute main region G1 and the first attribute subregion g1 are exposed. The drawing data E for preventing exposure is generated, and the widths of the first attribute subregion g1 and the second attribute subregion g2 are set to dimensions that can form a diffraction grating for visible light. Try to set.

  The upper part of FIG. 21 shows an example of the drawing pattern P (E) for drawing on the medium, and the lower part shows an enlarged view of the partial regions p1 to p3. Inside the identification marks m10 and m20, as shown as partial regions p1 and p2, a strip-like “black region” (first attribute subregion g1) and a strip-like “white region” (second attribute subregion) Striped patterns in which g2) are alternately arranged are formed. As described above, on the medium, the stripe pattern is formed as a concavo-convex structure that functions as a diffraction grating, and the reading operator can divide the pair of identification marks m10 into “convex” characters and “concave” characters. , M20 will be observed.

  Therefore, the width W1 of the “black region” (first attribute subregion g1) and the width W2 of the “white region” (second attribute subregion g2) formed on the actual medium are formed by a diffraction grating for visible light. It is necessary to set the width to be set.

  On the other hand, the difference between the width W1 and the width W2 causes a difference in brightness when the two identification marks m10 and m20 are compared and observed, so that the function of the diffraction grating is not impaired in practical use. It is preferable to set as large as possible. The inventor of the present application conducted an experiment to create an actual medium by setting various dimensions as the width W1 and the width W2. When the ratio between the width W1 and the width W2 is set to be five times or more, It was found that the difference in brightness when the two identification marks m10 and m20 are compared and observed can be recognized remarkably regardless of the illumination environment or the observation environment.

  Therefore, practically, the sub information pattern generation unit 180 has the width W1 of the first attribute sub-region g1 is five times the width W2 of the second attribute sub-region g2 for the closed region constituting the first identification mark m10. For the closed region constituting the second identification mark m20, the width W2 of the second attribute subregion g2 is set to be 5 times or more the width W1 of the first attribute subregion g1. (The example shown in FIG. 21 does not have a dimensional ratio that satisfies such a condition for the sake of illustration).

  Also, in order to make the brightness of the “convex” character when observing the “black convex medium” and the brightness of the “concave” character when observing the “black concave medium” as much as possible The sub-information pattern generation unit 180 uses the width W1 of the first attribute sub-region g1 in the closed region constituting the first identification mark m10 and the second attribute sub-region in the closed region constituting the second identification mark m20. The width W2 of the region g2 is set equal, and the width W2 of the second attribute sub-region g2 in the closed region constituting the first identification mark m10 and the first attribute in the closed region constituting the second identification mark m20 are set. It is preferable to set the width W1 of the subregion g1 equal.

  In other words, in the example shown in FIG. 21, the width W1 of the black region g1 in the partial region p1 is equal to the width W2 of the white region g2 in the partial region p2, and the width of the white region g2 in the partial region p1. The setting may be performed so that W2 is equal to the width W1 of the black region g1 in the partial region p2. If such a setting is made, the “black convex medium” and the “black concave medium” created based on the drawing pattern P (E) shown in FIG. )), The brightness of the “convex” character on the “black convex medium” is equal to the brightness of the “concave” character on the “black concave medium”, creating a unified media. It becomes possible.

  Here, for reference, the dimension values of the respective parts of the identification mark for which a good observation result was obtained by an experiment conducted by the inventor of the present application will be described as an example. First, in the partial region p1 shown in FIG. 21 (that is, in the first identification mark m10), the width W1 of the first attribute subregion g1 = 1.8 μm, the width W2 of the second attribute subregion g2 = 0. The thickness was 2 μm. On the other hand, in the partial region p2 (that is, in the second identification mark m20), the width W1 of the first attribute subregion g1 = 0.2 μm and the width W2 of the second attribute subregion g2 = 1.8 μm. In any case, the longitudinal dimension of each band-like region is a dimension obtained by extending both ends until reaching the contour line of each identification mark.

  When the above dimensions are employed, the grating line pitch of the diffraction grating is eventually 2 μm, which is a dimension that causes a sufficient diffraction phenomenon with respect to visible light. In the above embodiment, each bit figure F recorded in the main recording area Aα is a square having a side of 0.1 μm, and the step of the concavo-convex structure formed on the medium is set to 0.2 μm.

  It is preferable that the first identification mark m10 and the second identification mark m20 formed on the information recording medium have a size that allows visual observation. Of course, even a small mark that is difficult to observe with the naked eye can be observed using a magnifying glass or the like. However, in practice, a reading operator who has a medium in his hand reads the medium as a “black convex medium”. Or “black concave medium” is preferably made to be immediately recognizable by visual observation of the mark. Therefore, the sub information pattern generation unit 180 generates a sub information pattern in which the first identification mark m10 and the second identification mark m20 formed on the information recording medium have a size that can be visually observed. Is preferred. In the above embodiment, the individual identification marks m10 and m20 are set to have a size of about 3 mm in length and width on the medium.

  Subsequently, some variations of the identification mark used in the present invention will be described. FIG. 26 is a plan view showing the configuration and arrangement of the identification mark in the basic embodiment described so far. Actually, the drawing pattern P (E) is composed of the main information pattern Pα recorded in the main recording area Aα and the sub information pattern Pβ recorded in the sub recording area Aβ. Only the pattern Pβ is shown. The sub information pattern Pβ is a pattern having a first identification mark m10 indicating a “convex” character and a first identification mark m20 indicating a “concave” character. Depending on which of the marks looks bright, the interpretation method of the data bits recorded in the main recording area Aα is recognized.

  In carrying out the present invention, the positions of the first identification mark m10 and the second identification mark m20 on the medium are not particularly limited. Therefore, for example, the first identification mark m10 may be disposed in the upper left corner of the medium, and the second identification mark m20 may be disposed in the lower right corner. However, in practice, it is not preferable to dispose these two identification marks apart from each other. This is because the reading operator needs to compare the brightness by observing the two identification marks m10 and m20 in comparison. In order to compare the brightness of the identification marks so that the brightness can be easily compared, it is preferable to arrange the marks adjacent to each other.

  If the “convex” and “concave” characters are arranged adjacent to each other on the left and right as in the example shown in FIG. 26, the reading operator can easily compare the brightness. Therefore, in practice, it is preferable that the sub information pattern generation unit 180 generates the sub information pattern Pβ in which the first identification mark m10 and the second identification mark m20 are arranged adjacent to each other.

  Further, in order to further facilitate the comparative observation, it is also possible to generate the sub information pattern Pβ in which the closed region constituting the first identification mark and the closed region constituting the second identification mark are in contact with each other. is there. FIG. 27 (a) is an example in which the letters “convex” and “concave” are arranged next to each other so that their closed regions are in contact with each other. Since the closed region constituting the first identification mark m11 and the closed region constituting the second identification mark m21 are in contact with each other across the boundary line, the reading operator further compares the brightness of the two. It can be done easily. In the case of the illustrated example, the first identification mark m11 is a “convex” character, and the second identification mark m21 is a “concave” character. By reversing the top and bottom and fitting the upper part of the “convex” character, the identification mark fused as a whole has been successfully formed.

  On the other hand, FIG. 27B shows an example in which a “concave” character is embedded in a “convex” character. Since the “concave” character is in contact with the “convex” character with its outline as a boundary, the reading operator can more easily compare the brightness of the two. In this way, the sub information pattern Pβ in which the second identification mark m22 is embedded inside the first identification mark m12 may be generated. Conversely, the first identification mark m22 may include the first information pattern Pβ. The sub information pattern Pβ in which the identification mark m12 is embedded may be generated. In either case, since the external identification mark is in contact with the entire outline of the identification mark embedded therein as a boundary, the effect of facilitating comparative observation can be obtained.

  In the embodiment described so far, a mark designed with a “convex” character is used as the first identification mark, and a mark designed with a “concave” character is used as the second identification mark. Of course, the identification mark used when carrying out the present invention is not limited to the mark using these characters. The first identification mark is a mark indicating the first interpretation method for the data bits recorded in the main recording area Aα, and the second identification mark is a mark indicating the second interpretation method. Any mark may be used as long as the person can recognize one of the interpretation methods based on these identification marks.

  For example, the letter “A” may be used as the first identification mark and the letter “B” may be used as the second identification mark. In this case, for example, in a medium in which the character “A” appears bright, the convex portion is interpreted as a bit “1” and a concave portion is interpreted as bit “0”. If the arrangement of interpreting “0” and the concave portion as the bit “1” is made and the arrangement is transmitted to the reading worker, the reading worker can make the brightness of the characters “A / B” brighter. By the judgment, it is possible to recognize the correct data bit interpretation method.

  Of course, the identification mark does not necessarily have to be a character, and may be a mark such as a numeral, a symbol, or a figure. Moreover, each identification mark does not necessarily need to be configured by a single closed region, and may be configured by a plurality of closed regions. FIG. 28A is a plan view showing an example of an identification mark constituted by a figure. In addition, in this example, each identification mark is constituted by a plurality of closed regions.

  That is, the first identification mark m13 shown on the left side of FIG. 28A is a mark formed by combining two sets of closed areas m13a and m13b each formed of a triangle, and has a design that makes a “convex” character appear. It has become. On the other hand, the second identification mark m23 shown on the right side of FIG. 28 (b) is a mark formed by combining three sets of closed regions m23a, m23b, and m23c each having a rectangular shape. The design is reminiscent of the character.

  Thus, even when each identification mark is constituted by a plurality of closed regions, a striped pattern as illustrated in the partial region p1 of FIG. 21 is formed in the closed regions m13a and m13b, and the closed regions m23a, m23b, and m23c are formed. If a striped pattern as illustrated in the partial region p2 in FIG. 21 is formed in the inside, the first identification mark m13 is recognized as one mark as a whole, and the second identification mark m23 is also displayed as a whole. Therefore, the correct data bit interpretation method can be recognized by comparing the brightness of the two.

  Further, the identification mark is not necessarily constituted by a single character, numeral, symbol, or figure, and may be constituted by a combination thereof. For example, if an identification mark is composed of a combination of a plurality of characters, a sentence can be composed of the identification mark. FIG. 28 (b) shows an example of an identification mark constituting such a sentence. Specifically, in the example shown in FIG. 28 (b), a sentence composed of a character string “the convex portion is bit“ 1 ”” forms the first identification mark m14, and “the concave portion is a bit”. A sentence composed of a character string “1” is a second identification mark m24.

  FIG. 29 is a plan view of a drawing pattern P (E) having identification marks m14 and m24 according to the modification shown in FIG. In the case of this example, the text is recorded over two levels in the sub-recording area Aβ provided at the upper left corner of the drawing pattern P (E). The upper sentence is the first identification mark m14 “the convex part is bit“ 1 ”.” The lower sentence is the second identification mark m24 “the concave part is bit“ 1 ”.” . Of course, a stripe pattern as illustrated in the partial region p1 of FIG. 21 is formed inside each character of the upper sentence constituting the first identification mark m14, and the lower part constituting the second identification mark m24. A striped pattern exemplified in the partial region p2 of FIG. 21 is formed inside each character of the sentence.

  Therefore, if the medium created based on the drawing pattern P (E) is “black convex medium”, the first identification mark m14 is observed brighter. If there is, the second identification mark m24 is observed brighter. Eventually, the reading operator observes the sub-recording area Aβ of the medium he has obtained, and if the sentence “The convex part is bit“ 1 ”” appears bright, it is recorded in the main recording area Aα. For data bits, read processing that interprets the convex portion as bit “1” can be performed, and if the sentence “The concave portion is bit“ 1 ”” appears bright, the concave portion is interpreted as bit “1”. The reading process to be performed may be performed. FIG. 29 shows the latter observation mode.

  In short, the sub information pattern Pβ used in the present invention is the first information (one of two methods for interpreting data bits) consisting of letters, numbers, symbols, figures, or a part of these, or a combination thereof. A first identification mark having one or a plurality of closed regions for presenting information, and second information (letters, numbers, symbols, figures, parts thereof, or combinations thereof) Any pattern may be used as long as it has a second identification mark having one or more closed regions for presenting information indicating the other of the interpretation methods.

  Finally, referring to FIG. 30, another variation of the identification mark constituting the sub information pattern will be exemplified. FIG. 30 is a plan view showing a modified example in which an auxiliary common identification mark is further used as the sub information pattern in addition to the first identification mark and the second identification mark.

  The sub information pattern shown in the upper part of FIG. 30 includes a total of four sets of rectangles arranged in two rows. That is, a square central rectangle m15 is arranged at the center of the upper row, a square left rectangle m25a is arranged on the left side, and a square right rectangle m25b is arranged on the right side, In the lower row, a rectangular lower rectangle m30 having a horizontal width corresponding to the full width of these three sets of rectangular groups is arranged. In other words, three rectangles, a left rectangle m25a, a center rectangle m15, and a right rectangle m25b, are arranged adjacent to each other in the horizontal direction so that they are on the left, center, and right sides, respectively, and below these three sets of rectangles. The figure which has arrange | positioned the lower rectangle m30 so that it may adjoin in common is shown.

  Here, the center rectangle m15 constitutes a first identification mark, and the combination of the left rectangle m25a and the right rectangle m25b constitutes a second identification mark. The feature of this variation is that a lower rectangle m30 constituting an auxiliary common identification mark is further provided. The auxiliary common identification mark m30 should be called a third identification mark, and has optical characteristics different from those of the first identification mark and the second identification mark.

  The lower part of FIG. 30 shows an enlarged view (image in a circle) of each partial area of the sub information pattern shown in the upper part of FIG. That is, the image in the lower circle p1 is an enlarged view of the partial region p1 in the central rectangle m15 constituting the first identification mark shown in the upper row, and the image in the lower circle p2 is the second image shown in the upper row. Is an enlarged view of the partial area p2 in the left rectangle m25a (the same applies to the enlarged view of the partial area in the right rectangle m25b), and the image in the lower circle p3 is the auxiliary common identification mark shown in the upper stage FIG. 30 is an enlarged view of the partial region p3 in the lower rectangle m30 (also in FIG. 30, the dimensional ratio of each part is set ignoring the actual dimensional ratio).

  In the partial areas p1, p2 and p3 shown in the lower part of FIG. 30, as in the example described so far, elongated strip-shaped “black regions” and elongated strip-shaped “white regions” are alternately arranged. Thus, on the medium M, it functions as a diffraction grating for visible light. As in the embodiment described with reference to FIG. 21, each grating line forming these diffraction gratings is set to be in a direction parallel to the common arrangement axis Z. The illustrated example is an example in which the arrangement axis Z is set as an axis extending in the vertical direction in the figure, and therefore, stripe patterns extending in the vertical direction are formed in the partial regions p1, p2, and p3. Of course, the orientation of the arrangement axis Z may be set in an arbitrary direction.

  The enlarged view of the partial regions p1 and p2 shown in FIG. 30 is exactly the same as the enlarged view of the partial regions p1 and p2 shown in FIG. That is, when the stripe pattern in the partial area p1 constituting the first identification mark is compared with the stripe pattern in the partial area p2 constituting the second identification mark, the “black area” (first attribute sub-area g1) is compared. The width relationship W1 between the width W1 of the band and the width W2 of the band forming the “white region” (second attribute subregion g2) is reversed between the two. Specifically, in the illustrated example, W1> W2 for the partial region p1, whereas W1 <W2 for the partial region p2. As described above, the difference in the width relationship produces a difference in brightness during observation.

  On the other hand, for the striped pattern in the partial region p3 constituting the auxiliary common identification mark, in this embodiment, the width W1 of the band constituting the “black region” (first attribute subregion g1) and the “white region” ( The width W2 of the band constituting the second attribute subregion g2) is set equal. Eventually, W1> W2 is set for the first identification mark, W1 <W2 is set for the second identification mark, and W1 = W2 is set for the auxiliary common identification mark.

  As already described, even when the information recording medium M is generated using drawing data having the same sub information pattern as illustrated in FIG. 30, the black region is convex due to the difference in beam exposure and patterning processing. There is a difference between a “black convex medium” or a “black concave medium” in which the black region is concave. Therefore, in the case of the information recording medium M created by the information storage device according to the present invention, the sub information pattern is observed, and the occupied area of the “black region” (first attribute sub region g1) is larger. When the second identification mark looks bright, it is determined as “black convex medium”, and when the second identification mark whose “occupied area of the“ white region ”(second attribute subregion g2) is wider appears bright. The point that can be determined as “black concave medium” is as already described.

  The important point in the embodiment shown in FIG. 30 is that the first identification mark m15 and the second identification mark at the time of observation depend on whether the actual medium M is “black convex medium” or “black concave medium”. Although the brightness relationship between m25 (m25a and m25b) is reversed, the brightness of the auxiliary common identification mark m30 is always the brightness of the first identification mark m15 and the brightness of the second identification mark m25. It is an intermediate point. In particular, in the embodiment shown in FIG. 30, since the auxiliary common identification mark m30 is set to W1 = W2, depending on whether the actual medium M is “black convex medium” or “black concave medium”. No difference occurs in the brightness of the auxiliary common identification mark m30.

  The role of the auxiliary common identification mark m30 is that the first identification mark m15 is a “black convex medium” in which the first identification mark m15 is observed brighter than the second identification mark m25, by simultaneous observation with the first identification mark m15. The first mark indicating that the medium is a “black convex medium”, and the second identification mark m25 is observed to be brighter than the first identification mark m15. In the case of “medium”, the second mark indicating that the medium is “black concave medium” is formed by simultaneous observation with the second identification mark m25.

  Such a role will be described in the specific embodiment of FIG. FIG. 31 is a plan view showing an observation mode of each identification mark in the modification shown in FIG. In FIG. 31, three types of hatching are performed in each region, but the hatched region by the mesh is observed brightly, the hatched region by the dots is observed darkly, and the hatched region by the diagonal lines is at an intermediate brightness. It shows that it is observed.

  FIG. 31 (a) shows an observation mode of “black convex medium”, where the first identification mark m15 is bright, the second identification mark m25 is dark, and the auxiliary common identification mark m30 has an intermediate brightness. Observed. For this reason, the observer's eyes recognize the bright first identification mark m15 and the intermediate common auxiliary auxiliary identification mark m30 as a merged mark. Specifically, as shown in a thick frame in the figure, the observer grasps the first mark indicating the character “convex” and recognizes the medium M as “black convex medium”. it can. In other words, this sub-information pattern indicates an interpretation method that “the convex portion is bit“ 1 ””.

  On the other hand, FIG. 31B shows an observation mode of the “black concave medium”, where the second identification mark m25 is bright, the first identification mark m15 is dark, and the auxiliary common identification mark m30 is intermediate bright. It is observed. For this reason, the portion of the bright second identification mark m25 and the intermediate common auxiliary auxiliary identification mark m30 is grasped by the observer's eyes as one fused mark. Specifically, as shown by a thick frame in the figure, the observer grasps the second mark indicating the character “concave” and recognizes the medium M as “black concave medium”. it can. In other words, the sub information pattern indicates an interpretation method of “the recess is bit“ 1 ””.

  After all, when the variation illustrated in FIG. 30 is implemented, the sub information pattern generation unit 180 further includes the sub information having the auxiliary common identification mark m30 in addition to the first identification mark m15 and the second identification mark m25. A function for generating a pattern may be provided. Here, the auxiliary common identification mark m30 is an identification mark having one or a plurality of closed regions for presenting auxiliary common information made up of letters, numbers, symbols, figures, parts thereof, or combinations thereof. I just need it.

  The important point here is that, in the closed region constituting the auxiliary common identification mark m30, as shown as a partial region p3 in FIG. 30, the arrangement axis Z (in the illustrated example, the vertical axis in the figure) The strip-shaped first attribute sub-region g1 and the strip-shaped second attribute sub-region g2 extending in the parallel direction are alternately arranged in a direction orthogonal to the arrangement axis Z (in the illustrated example, the left-right direction). On the actual medium M, a diffraction grating for visible light is formed.

  In the embodiment shown in FIG. 30, the width W1 of the first attribute subregion g1 and the width W2 of the second attribute subregion g2 in the auxiliary common identification mark m30 are set to be equal. As described above, this is a consideration for preventing a difference in brightness of the auxiliary common identification mark m30 depending on whether the actual medium M is “black convex medium” or “black concave medium”. However, in the auxiliary common identification mark m30, it is not always necessary to set W1 = W2, and there may be a slight difference between the two.

  The important point is that the difference between the width W1 of the first attribute sub-region g1 and the width W2 of the second attribute sub-region g2 in the auxiliary common identification mark m30 is the first identification mark m15 and the second identification mark m25. The difference is that the width is set smaller than the difference between the width W1 of the first attribute subregion g1 and the width W2 of the second attribute subregion g2. With such a setting, whether the actual medium M is “black convex medium” or “black concave medium”, the brightness of the auxiliary common identification mark m30 is the brightness of the first identification mark m15. And the brightness of the second identification mark m25, the medium can be used as an auxiliary mark that is commonly observed in any medium.

  The feature of the embodiment shown in FIG. 30 is that the combination of the first identification mark m15 and the auxiliary common identification mark m30 is a first mark (first mark) indicating a first interpretation method of the data bits indicated by the main information pattern. A mark indicating the character “convex”), and a second interpretation method of the data bits indicated by the main information pattern by the combination of the second identification mark m25 and the auxiliary common identification mark m30. A mark (a mark indicating the character “concave”) is formed. That is, the sub-information pattern is configured by the four sets of rectangles shown in the upper part of FIG. Since the identification marks are configured, the first mark indicating the character “convex” and the second mark indicating the character “concave” can be displayed.

  Of course, theoretically, even if the auxiliary common identification mark m30 is not provided, the first identification mark (mark made of a single square) consisting of the center rectangle m15 can be observed brightly, or the left rectangle m25a and the right side Depending on whether the second identification mark (mark consisting of a pair of squares) made of the rectangle m25b can be observed brightly, it is also possible to indicate the method of interpreting the data bits. However, as shown in FIG. 31, if the auxiliary common identification mark m30 is added, the first mark indicating the character “convex” and the second mark indicating the character “concave” can be displayed. The information pattern is a mark that directly indicates whether “bit“ 1 ”” is a convex portion or a concave portion, and the observer can recognize the interpretation method of the data bit more intuitively.

  Note that the characters “convex” and “concave” are not necessarily used as the first mark and the second mark. For example, in FIG. 28B, the first identification mark m14 “the convex part is bit“ 1 ”” and the second identification mark m24 “the concave part is bit“ 1 ”” are used. However, it is also possible to use the auxiliary common identification mark described above in this embodiment. Specifically, for example, the “protruding part” portion is the first identification mark, the “concave portion” portion is the second identification mark, and the “bit“ 1 ”” portion is the auxiliary common identification. It can be a mark.

<<< §10. Variations in the structure of information recording media >>
In §2, several variations of the structure of the information recording medium created by the information storage device according to the prior invention were described with reference to FIG. Here, variations of the structure of the information recording medium created by the information storage device according to the present invention will be described.

  In the case of the embodiments described in §7 and §8, the patterning apparatus 300 uses the first attribute region (first attribute main region G1 and first attribute subregion g1) and second attribute region (second attribute main region). A physical structure having a concavo-convex structure including a concave portion C indicating one of G2 and the second attribute subregion g2) and a convex portion V indicating the other is formed. On the other hand, FIG. 5 (c) shows a modification in which the additional layer 32 is formed on the surface of the convex portion V in the physical structure having such a concave-convex structure as a variation of the invention of the prior application. Thus, the modification in which the additional layer is formed on the surface of the convex portion V is also effective in the present invention.

  32 to 35 are side sectional views showing various variations of the information recording medium in which information is written by the information storage device shown in FIG. 18, and the upper diagram (a) shows the first identification. The lower section (b) shows the side section of the partial area p2 in which the mark m10 is recorded, and the lower figure (b) shows the side section of the partial area p2 in which the second identification mark m20 is recorded. The illustration of the structure is omitted).

  The feature of the modification shown in FIG. 32 is that an additional layer 61 is further provided on the surface of the convex portion of the substrate 60 after the processing for forming the concavo-convex structure on the upper surface is performed. Here, as the additional layer 61, a layer made of a light reflective material is used. In order to create a physical structure as shown in FIG. 32, the patterning apparatus 300 should be provided with a function of forming the additional layer 61 made of a light reflective material on the surface of the convex portion of the layer 60 to be molded. Good.

  As described above, when the additional layer 61 made of a light reflective material is formed on the surface of the convex portion, when the first identification mark m10 and the second identification mark m20 are compared, the brightness of both is increased. The difference can be made more prominent, and the effect of facilitating observation by the reading operator can be obtained. FIGS. 32 (a) and 32 (b) show the structure of a “black concave medium”, similar to the medium M5 shown in FIG. 24, and the light beam L9 incident on the convex portion is reflected upward and observed. Most of the light beam L10 incident on the concave portion is scattered and disappears. Accordingly, the first identification mark m10 (FIG. 32 (a)), which has a larger area occupied by the recesses than the area occupied by the protrusions, appears darker, and the area occupied by the protrusions is wider than the area occupied by the recesses. The second identification mark m20 (FIG. 32 (b)) appears bright.

  At this time, if the additional layer 61 made of a light-reflective material is formed on the surface of the convex portion, the reflectance of the light beam L9 incident on the convex portion can be improved, so the second identification mark m20 (FIG. 32 (b)) can be brightened. Therefore, the comparative observation by the reading operator can be made easier.

  In the case of a medium employing the structure according to the modification shown in FIG. 32, the width of the first attribute subregion g1 (recessed portion) in the partial region p1 (FIG. 32 (a)) is W1 = 19 μm, and the second attribute subregion. The width of the region g2 (convex portion) is W2 = 1 μm, the width of the first attribute subregion g1 (concave portion) in the partial region p2 (FIG. 32B) is W1 = 1 μm, and the second attribute subregion g2 (convex portion) ) Was set to W2 = 19 μm, and the lattice line pitch was set to 20 μm. When observed from above, both identification marks m10 and m20 could be confirmed in good condition by reflected diffracted light. .

  On the other hand, in the modification shown in FIG. 33, the patterning device 300 performs a patterning process on the substrate 65 made of a light-transmitting material, thereby forming a concavo-convex structure on the surface of the substrate 65 (upper surface in the drawing). Furthermore, this is an example in which an additional layer 66 made of a light shielding material is formed on the back surface (lower surface in the figure) of the substrate 65. Even in the case of the medium composed of the substrate 65, the reflected light of the illumination light irradiated from above is observed from above to recognize each identification mark, but the substrate 65 is made of a translucent material. Therefore, if the illumination light L11 from the back surface is transmitted upward, it may adversely affect the observation of the identification mark.

  In the structure shown in FIG. 33, the additional layer 66 made of a light-shielding material formed on the back surface of the substrate 65 transmits the illumination light L11 from the back surface upward, which adversely affects the observation of the identification mark. It serves to prevent things. When the substrate 65 is made of a non-light-transmitting material, it is not necessary to provide the additional layer 66 on the back surface. However, when the substrate 65 is made of a light-transmitting material, the back surface is light-shielding like the example shown in the drawing. An additional layer 66 made of a material is preferably provided.

  In each of the embodiments described so far, each identification mark is observed by observing the reflected light on the upper surface of the illumination light irradiated from above on the medium having the concavo-convex structure formed on the upper surface. However, in the case of a medium using a substrate 65 made of a translucent material as in the example shown in FIG. 34, the transmitted light from the upper surface of the illumination light irradiated on the lower surface from below is transmitted upward. It is also possible to recognize each identification mark by observing.

  In FIG. 34, the light rays L12 and L13 that are transmitted from the lower side to the upper side of the light-transmitting substrate 65 are drawn by a one-dot chain line, but the light ray L12 is a light that passes through the convex portion V and travels upward. The light beam L13 is light that passes through the recess C and travels upward. Theoretically, unless the substrate 65 is a completely transparent material having 100% translucency, a part of the transmitted light attenuates while traveling through the substrate 65. The intensity of the light beam L12 that has passed through is slightly lower than the intensity of the light beam L13 that has passed through the recess C. Therefore, in the case of the illustrated example, the first identification mark m10 (FIG. 34 (a)) in which the occupied area of the concave portion C is larger than the occupied area of the convex portion V appears slightly brighter, and the occupied area of the convex portion V is larger. The second identification mark m20 (FIG. 34 (b)), which is wider than the area occupied by the recess C, appears slightly darker.

  However, in the case of the configuration shown in FIG. 34, the difference in brightness between the two identification marks observed by the transmitted light is very small, so that the function as the identification mark according to the present invention can be sufficiently achieved in practice. Can not. Therefore, actually, it is preferable to form an additional layer 67 made of a light-shielding material on the upper surface of the convex portion of the substrate 65 as in the example shown in FIG. In order to create a medium having the structure shown in FIG. 35, the patterning apparatus 300 forms a concavo-convex structure on the upper surface by performing a patterning process on the substrate 65 made of a light-transmitting material. What is necessary is just to perform the process which forms the additional layer 67 which consists of a light-shielding material on the surface of the convex part V. FIG.

  In the case of the medium shown in FIG. 35, the light beam L13 that is transmitted through the concave portion C is observed as it is transmitted upward, but the light beam L12 that is transmitted through the convex portion V is a light shielding material. It is blocked by the additional layer 67 and is not observed above. Therefore, in the case of the illustrated example, the first identification mark m10 (FIG. 35 (a)) whose area occupied by the concave portion C is larger than the area occupied by the convex portion V looks brighter, and the area occupied by the convex portion V is larger. The second identification mark m20 (FIG. 35 (b)), which is wider than the area occupied by the recess C, appears dark. By forming the additional layer 67 made of a light shielding material, the difference in brightness between the identification marks becomes remarkable, and the function as the identification mark according to the present invention can be sufficiently achieved.

  35, the width of the first attribute sub-region g1 (concave portion) in the partial region p1 (FIG. 35 (a)) is W1 = 19 μm and the second attribute. The width of the subregion g2 (convex portion) is W2 = 1 μm, the width of the first attribute subregion g1 (concave portion) in the partial region p2 (FIG. 35B) is W1 = 1 μm, and the second attribute subregion g2 (convex) Part) is set to W2 = 19 μm, and the lattice line pitch is set to 20 μm. When observed from above, both of the identification marks m10 and m20 can be confirmed in good condition by the transmitted diffracted light. It was.

  As described above, several variations of the information recording medium having the concavo-convex structure formed on the surface of the substrate have been described. However, in carrying out the present invention, the physical structure indicating the bit information is not necessarily limited to the concavo-convex structure. Instead, it is also possible to adopt a network structure as illustrated in FIG. 5 (a) as a modification of the prior invention. In this case, the patterning apparatus 300 includes a first attribute area (first attribute main area G1 and first attribute subarea g1) and a second attribute area (second attribute main area G2 and second attribute subarea g2). What is necessary is just to form the network structure which consists of the through-hole H which shows either, and the non-hole part N which shows the other.

  In this case, each data bit of the digital data to be stored is composed of a through hole H indicating one of the bits “1” and “0” and a non-hole N indicating the other in the main recording area Pα. It will be recorded as a network structure. For example, in the network structure 12 shown in FIG. 5 (a), a position indicated by a thick alternate long and short dash line (a position corresponding to a lattice point L where a bit is recorded) is a through hole H or a non-hole portion N (through hole The bit “1” and the bit “0” are represented as shown in FIG.

  On the other hand, information indicating a data bit interpretation method is recorded as information of a pair of identification marks in the sub-recording area Pβ.

  36 to 39 are side sectional views showing an information recording medium having a network structure created by the information storage device shown in FIG. In either case, the upper diagram (a) shows a side cross-section of the partial region p1 where the first identification mark m10 is recorded, and the lower diagram (b) shows the partial region p2 where the second identification mark m20 is recorded. A side cross section is shown (all show only a cut surface and illustration of a back structure is omitted).

  FIG. 36 shows a side cross section of partial regions p1 and p2 in an information recording medium constituted by a substrate 70 made of a network structure on which no additional layer is formed. Here, first, let us consider a case where each identification mark is observed by observing reflected light on the upper surface of illumination light irradiated from above on this information recording medium. In this case, the light beam L14 incident on the non-hole portion N is reflected on the upper surface of the non-hole portion N and observed above as shown in the figure. On the other hand, the light beam L15 incident on the through hole H is transmitted below the medium as shown in the figure, or collides with the side surface of the through hole H and is scattered.

  Therefore, the first identification mark m10 (FIG. 36 (a)) having a larger occupied area of the through hole H than the occupied area of the non-hole part N looks dark, and the occupied area of the non-hole part N penetrates. The second identification mark m20 (FIG. 36 (b)) wider than the area occupied by the hole H appears bright. Here, a mark indicating an interpretation method of “non-hole portion N is bit“ 1 ”” is used as identification mark m10, and a mark indicating an interpretation method of “through hole H is bit“ 1 ”” is used as identification mark m20. If used, each of the identification marks m10 and m20 functions normally as a mark indicating a data bit interpretation method.

  That is, in the example shown in FIG. 36, since the second identification mark m20 looks brighter, an interpretation method of “through hole H is bit“ 1 ”” is adopted. The correct interpretation of the data bits shown in FIG.

  On the other hand, in the modification shown in FIG. 37, an additional layer 71 is further provided on the upper surface of the substrate 70 made of the network structure shown in FIG. Here, as the additional layer 71, a layer made of a light reflective material is used. In order to create a physical structure as shown in FIG. 37, the patterning apparatus 300 is provided with a light reflective property on one surface (the upper surface in the illustrated example) of the non-hole portion N of the substrate 70 made of a network structure. A function of forming an additional layer made of a material may be provided.

  As described above, when the additional layer 71 made of a light-reflective material is formed on the upper surface of the non-hole portion N, when the first identification mark m10 and the second identification mark m20 are compared, the brightness of both of them is increased. The difference in thickness can be further conspicuous, and an effect of facilitating observation by the reading operator can be obtained. That is, when the additional layer 71 is formed, the point that the light beam L15 incident on the through hole H is not observed above is the same, but the reflectance of the light beam L14 incident on the non-hole N can be improved. This makes it possible to make the identification mark brighter and to make comparison observation by the reading operator easier.

  As described above, the description has been given on the assumption that each identification mark is observed by observing the reflected light on the upper surface of the illumination light irradiated from above with respect to the medium composed of the network structure. In the case of a medium composed of a body, each identification mark can be recognized by observing the transmitted light from the upper surface of the illumination light irradiated on the lower surface from below. FIG. 38 is a side sectional view showing an example in which a substrate 70 made of a network structure is made of a non-translucent material and illumination light from below is observed from above.

  Since the substrate 70 is made of a non-translucent material, the light beam L17 incident on the non-hole N from below is prevented from transmitting upward, but a part of the light beam L16 incident on the through hole H is upward. (Of course, part of the light collides with the side surface of the through hole H and is scattered and disappears). Therefore, in the case of the illustrated example, the first identification mark m10 (FIG. 38 (a)) in which the occupied area of the through hole H is larger than the occupied area of the non-hole part N appears brighter, and the non-hole part N The second identification mark m20 (FIG. 38 (b)) whose occupied area is larger than the occupied area of the through hole H will appear dark. Therefore, for the substrate 70 made of a net-like structure, it is also possible to confirm the comparison of both identification marks by observing the transmitted light from the upper surface of the illumination light irradiated from the lower surface to the lower surface.

  In the modification shown in FIG. 39, even when the substrate 75 made of a net-like structure is made using a translucent material, a mode in which illumination light from below is observed from above can be adopted. An additional layer 76 is further provided on the upper surface. Here, as the additional layer 76, a layer made of a light shielding material is used. In order to create a physical structure as shown in FIG. 39, a patterning process is performed on a substrate made of a light-transmitting material in the patterning apparatus 300 to form a substrate 75 having a network structure. A function for forming the additional layer 76 made of a light-shielding material may be provided on one side of the hole N.

  In the case of the medium shown in FIG. 39, the light beam L18 transmitted through the through-hole H is transmitted through the top as it is, but the light beam L19 attempting to transmit through the non-hole portion N is a light-shielding material. It is blocked by the additional layer 76 and is not observed above. Therefore, in the case of the illustrated example, the first identification mark m10 (FIG. 39 (a)) in which the occupied area of the through hole H is larger than the occupied area of the non-hole part N appears brighter, and the non-hole part N The second identification mark m20 (FIG. 39 (b)) whose occupied area is wider than the occupied area of the through hole H will appear dark. Even if the substrate 75 is made of a light-transmitting material, the difference in brightness between the two identification marks becomes remarkable due to the formation of the additional layer 76 made of a light-shielding material, and the function as the identification mark according to the present invention is sufficient. Can be fulfilled.

  In the above, several variations of the structure of the information recording medium have been described. On the contrary, the reflection light observation on the upper surface of the illumination light irradiated from above the medium is assumed to be reflected from the upper side. It should be noted that the relationship between the brightness and darkness of each identification mark is reversed when the transmission light from the upper surface of the illumination light irradiated on is assumed to be observed from above.

  For example, since the medium shown in FIG. 32 is a medium premised on reflection observation, the first identification mark m10 is a mark indicating that “the convex portion is bit“ 1 ””, and the second identification mark m20. May be used as a mark indicating that the “recess is bit“ 1 ””, but the medium shown in FIG. 35 is a medium premised on transmission observation. It is necessary to use a mark indicating “1” and the second identification mark m20 as a mark indicating that the “convex portion is bit“ 1 ””. In other words, the medium shown in FIG. 32 and the medium shown in FIG. 35 have a physically equivalent structure, but when the medium shown in FIG. 32 is reflected and observed, the second identification mark m20 (FIG. 32 (b)) looks brighter, but when the medium shown in FIG. 35 is observed through the transmission, the first identification mark m10 (FIG. 35 (a)) looks brighter.

  Similarly, since the medium shown in FIG. 37 is a medium premised on reflection observation, the first identification mark m10 is a mark indicating that “the non-hole portion N is bit“ 1 ””, and the second The identification mark m20 may be a mark indicating that “the through-hole H is bit“ 1 ””. However, since the medium shown in FIG. 39 is a medium premised on transmission observation, the first identification mark m10 is used. Is a mark indicating that “the through hole H is a bit“ 1 ””, and the second identification mark m20 needs to be a mark indicating that “the non-hole portion N is a bit“ 1 ””. In other words, the medium shown in FIG. 37 and the medium shown in FIG. 39 have a physically equivalent structure, but when the medium shown in FIG. 37 is reflected and observed, the second identification mark m20 (FIG. 37 (b)) looks brighter, but when the medium shown in FIG. 39 is viewed through, the first identification mark m10 (FIG. 39 (a)) appears brighter.

  Actually, at the time when the drawing data E is created by the storage processing computer 100 ′, it is impossible to predict what kind of medium will be finally created by the patterning device 300. Therefore, in practice, as information indicating the interpretation method of the data bits indicated by the respective identification marks m10 and m20, basically, information on the premise that reflection observation is performed is recorded, and reading work is performed. When the person compares the identification marks m10 and m20 by transmission observation, an arrangement may be made to reverse the data bit interpretation method.

  In addition, specific materials constituting each additional layer described above are as described in §2. For example, as the light reflecting material, metals such as aluminum, nickel, titanium, silver, chromium, silicon, molybdenum, and platinum, alloys of these metals, oxides, nitrides, and the like can be used. For example, a material made of a compound such as a metal oxide or nitride can be used. Of course, as described in §2, instead of forming another layer having a clear interface as in the additional layer, the same effect can be obtained by doping impurities on the surface on which the additional layer is to be formed. it can.

<<<< §11. Information storage method according to the present invention >>
Finally, a processing procedure when the present invention is grasped as a method invention called an information storage method will be described with reference to a flowchart of FIG. The information storage process shown in FIG. 40 is a process for executing an information storage method in which digital data is written and stored in an information recording medium, and includes steps S31 to S36 as shown. Here, the steps S31 to S34 are processing steps executed by the storage processing computer 100 'shown in FIG. 18, and the step S35 is a processing executed by the beam exposure apparatus 200 shown in FIG. Step S36 is a processing step executed by the patterning apparatus 300 shown in FIG.

  First, in step S31, a data input step for inputting digital data D to be stored is executed. The processing content at this stage is the same as the processing content of step S11 in the prior application invention shown in FIG.

  Subsequently, in step S32, a main information pattern generation stage for generating a main information pattern Pα indicating information of individual data bits constituting the digital data D input in step S31 is executed. The processing contents at this stage are the same as the processing contents of steps S12 to S15 in the prior application invention shown in FIG.

  The important point here is that the main information pattern Pα generated in the main information pattern generation stage is the first attribute main area G1 (black area) and the first attribute main area G3 as illustrated in the partial area p3 of FIG. A predetermined point corresponding to each data bit exists in the first attribute main area G1 or in the second attribute main area G2 and is composed of the two attribute main area G2 (white area). Or the difference is a pattern in which binary information of individual data bits is expressed.

  On the other hand, in step S33, a sub-information pattern generation stage for generating a sub-information pattern Pβ indicating how to interpret the data bits indicated by the main information pattern Pα is executed. This stage is a new stage that does not exist in the invention of the prior application, and the specific processing content is as described above as the processing function of the sub information pattern generation unit 180.

  The important point here is that, as shown in FIG. 21, the sub information pattern Pβ presents first information consisting of letters, numbers, symbols, figures, parts thereof, or combinations thereof. One or a plurality of first identification marks m10 having one or a plurality of closed regions, and one or more for presenting second information composed of letters, numbers, symbols, figures, parts thereof, or combinations thereof And a second identification mark m20 having a closed region.

  Moreover, as illustrated in the partial region p1 of FIG. 21, the first attribute subregion in the form of a band extending in a direction parallel to the predetermined arrangement axis Z is present in the closed region constituting the first identification mark m10. g1 (black region) and strip-shaped second attribute subregion g2 (white region) are alternately arranged in a direction orthogonal to the arrangement axis Z, and are illustrated in the partial region p2 of FIG. As shown, in the closed region constituting the second identification mark m20, a strip-shaped first attribute subregion g1 (black region) extending in a direction parallel to the arrangement axis Z and a strip-shaped second attribute subregion g2 (White areas) are alternately arranged in a direction orthogonal to the arrangement axis Z.

  Here, with respect to the closed region constituting the first identification mark m10, the width W1 of the first attribute subregion g1 is set to be wider than the width W2 of the second attribute subregion g2, and the second identification mark An important feature of the closed region constituting m20 is that the width W2 of the second attribute subregion g2 is set larger than the width W1 of the first attribute subregion g1.

  In step S34, a drawing data generation stage for generating drawing data E for drawing the main information pattern Pα and the sub information pattern Pβ is executed. This processing content is substantially the same as the processing content of step S16 in the prior application invention shown in FIG. That is, in step S16, the drawing data E is generated based on the main information pattern Pα. In step S34, the drawing data E is generated based on the combined pattern obtained by synthesizing the sub information pattern Pβ with the main information pattern Pα. Will be done.

  Here, the drawing data E generated in the drawing data generation stage exposes the first attribute main region G1 and the first attribute subregion g1, and the second attribute main region G2 and the second attribute subregion. It is the drawing data for preventing exposure to g2, or the second attribute main region G2 and the second attribute subregion g2 are exposed, and the first attribute main region G1 and It is drawing data for preventing exposure to the first attribute subregion g1, and the widths of the first attribute subregion g1 and the second attribute subregion g2 constitute a diffraction grating for visible light. The dimension setting is performed so that the dimension becomes possible.

  Subsequently, in step S35, a beam exposure step is performed in which beam exposure using an electron beam or laser light is performed on the substrate serving as the information recording medium, based on the drawing data E generated in step S34. The processing content at this stage is the same as the processing content of step S17 in the prior application invention shown in FIG.

  In the final step S36, a patterning process is performed to generate an information recording medium on which a physical structure pattern corresponding to the drawing data E is formed by performing a patterning process on the exposed substrate. The processing content at this stage is the same as the processing content of step S18 in the prior application invention shown in FIG. Of course, when the structures according to various variations described in §10 are adopted, a necessary additional layer is formed in step S36.

10: Molded layer (before processing)
11: Molded layer (after processing)
12: Network structure 13: Molded layer (after processing)
20: resist layer 21: exposed portion 22: non-exposed portion 23: remaining portion 24: remaining portion 31: additional layer (formed on the entire surface)
32: Additional layer (formed on the protrusion)
33: Additional layer (formed in the recess)
40: Support layer 51: Molded layer 60: Substrate 61: Additional layer 65 made of light reflecting material 65: Substrate made of light transmissive material 66: Additional layer made of light shielding material 67: Additional layer 70 made of light shielding material : Substrate 71 made of network structure: additional layer 75 made of light reflective material: substrate 76 made of translucent material: additional layer 100, 100 'made of light shielding material: storage processing computer 110: data input unit 120 : Unit data generation unit 130: Unit bit matrix generation unit 140: Unit bit graphic pattern generation light rain 150: Unit recording graphic pattern generation units 160 and 160 ′: Drawing data generation unit 170: Main information pattern generation unit 180: Sub information Pattern generator 200: Beam exposure device 300: Patterning device 310: Development processing unit 320: Etching processing unit 400: Image photographing device 410: Image element 420: Magnifying optical system 430: Scanning mechanism 500: Reading processing computer 510: Captured image storage unit 520: Bit recording area recognition unit 530: Unit bit matrix recognition unit 540: Scan control unit 550: Data restoration unit Ab, Ab (I): Bit recording areas Au, Au (11) to Au (33): Unit recording area Aα: Main recording area Aβ: Subrecording area Aβ1: First subrecording area Aβ2: Second subrecording area B (U1) , B (Ui): Unit bit matrix C: Concave portion D: Digital data E to be saved E: Drawing data F: Bit figure G1: First attribute main region G2: Second attribute main region g1: First attribute subregion g2 : Second attribute sub-region H: through-hole L: grid points L1 to L19: light ray M: information recording medium M ': information recording medium M0: duplicate creation medium M1: original information recording medium M2: duplicated information Record Recording medium M3: Original information recording medium M4: Duplicated information recording medium M5: Information recording medium (black concave medium)
M6: Information recording medium (black convex medium)
m1 to m25: Identification mark m30: Auxiliary common identification marks m13a, m13b: Closed areas m23a, m23b, m23c of the identification mark m13: Closed areas m25a, m25b of the identification mark m23 N: Non-closed areas of the identification mark m25 Hole P (E): Drawing pattern P (U1), P (Ui): Unit bit figure pattern Pα: Main information pattern Pβ: Sub information patterns p1 to p3: Partial areas Q, Q1 to Q43: Alignment mark R (U1) to R (U4), R (Ui): Unit recording graphic pattern S: Exposure target substrates S11 to S36: Steps U1 to U4 of the flowchart, Ui: Unit data u: Predetermined bit length V: Convex W1 : Width W2 of the first attribute sub-region: width X of the second attribute sub-region X: horizontal coordinate axes X1 to X7: horizontal grid lines Y: vertical coordinate axes Y1 to Y7: vertical grid lines Z: arrangement axis

Claims (9)

An information recording medium in which digital data is written,
Information of individual data bits constituting digital data to be stored is indicated by arranging a bit figure at a position corresponding to bit “1” and nothing at a position corresponding to bit “0”. A main recording area in which a main information pattern is recorded;
A sub-recording area in which a sub-information pattern indicating how to interpret the data bits indicated by the main information pattern is recorded,
The main recording area has a concavo-convex structure composed of a concave part indicating one of the black area and the white area and a convex part indicating the other when the inside of the bit figure is called a black area and the outside is called a white area. Formed,
Whether the information recording medium in the sub-recording area is a black convex medium in which the black area is a convex part and the white area is a concave part, or is a black concave medium in which the white area is a convex part and the black area is a concave part An information recording medium on which an identification mark for making a judgment is recorded. An information recording medium in which digital data is written,
Information of individual data bits constituting digital data to be stored is indicated by arranging a bit figure at a position corresponding to bit “0” and nothing at a position corresponding to bit “1”. A main recording area in which a main information pattern is recorded;
A sub-recording area in which a sub-information pattern indicating how to interpret the data bits indicated by the main information pattern is recorded,
The main recording area has a concavo-convex structure composed of a concave part indicating one of the black area and the white area and a convex part indicating the other when the inside of the bit figure is called a black area and the outside is called a white area. Formed,
Whether the information recording medium in the sub-recording area is a black convex medium in which the black area is a convex part and the white area is a concave part, or is a black concave medium in which the white area is a convex part and the black area is a concave part An information recording medium on which an identification mark for making a judgment is recorded. The information recording medium according to claim 1 or 2,
In the sub-recording area, a first identification mark and a second identification mark that are observable with the naked eye are recorded, and the light and darkness are between the first identification mark and the second identification mark during the naked eye observation. It is configured so that the difference is caused by the criterion of "which of the pair of the identification mark appears bright" when comparing observed and the second identification mark and the first identification mark, "black convex medium" An information recording medium characterized in that it can be recognized whether it is a “black concave medium” or not. An information recording medium in which digital data is written,
Information of individual data bits constituting digital data to be stored is indicated by arranging a bit figure at a position corresponding to bit “1” and nothing at a position corresponding to bit “0”. A main recording area in which a main information pattern is recorded;
A sub-recording area in which a sub-information pattern indicating how to interpret the data bits indicated by the main information pattern is recorded,
In the main recording area, when the inside of the bit figure is called a black area and the outside is called a white area , the main recording area has a mesh-like shape composed of a through hole indicating one of the black area and the white area and a non-hole portion indicating the other. The structure is formed,
In the sub-recording area, the information recording medium is a black through-hole medium in which a black area is a through hole and a white area is a non-hole, or a black area in which a white area is a through-hole and a black area is a non-hole. An information recording medium on which an identification mark for determining whether the medium is a non-hole medium is recorded. An information recording medium in which digital data is written,
Information of individual data bits constituting digital data to be stored is indicated by arranging a bit figure at a position corresponding to bit “0” and nothing at a position corresponding to bit “1”. A main recording area in which a main information pattern is recorded;
A sub-recording area in which a sub-information pattern indicating how to interpret the data bits indicated by the main information pattern is recorded,
In the main recording area, when the inside of the bit figure is called a black area and the outside is called a white area , the main recording area has a mesh-like shape composed of a through hole indicating one of the black area and the white area and a non-hole portion indicating the other. The structure is formed,
In the sub-recording area, the information recording medium is a black through-hole medium in which a black area is a through hole and a white area is a non-hole, or a black area in which a white area is a through-hole and a black area is a non-hole. An information recording medium on which an identification mark for determining whether the medium is a non-hole medium is recorded. The information recording medium according to claim 4 or 5,
In the sub-recording area, a first identification mark and a second identification mark that are observable with the naked eye are recorded, and the light and darkness are between the first identification mark and the second identification mark during the naked eye observation. It is configured so that the difference is caused, the first by a reference of "which of the pair of the identification mark appears bright" when said second comparing observed the identification mark with the identification mark, "black holes medium Or “black non-perforated medium”. An information recording medium characterized in that it can be recognized. The information recording medium according to claim 3 or 6,
Each of the first identification mark and the second identification mark is constituted by a closed region including a first attribute sub-region and a second attribute sub-region,
The first attribute sub region and the second attribute subregions, both are arranged side by side alternately a belt-shaped region extending in a predetermined direction, and the closed region constituting the first identification mark, The width of the first attribute sub-region is set to be wider than the width of the second attribute sub-region, and for the closed region constituting the second identification mark, the width of the second attribute sub-region is the An information recording medium, wherein the information recording medium is set to be wider than the width of the first attribute subregion. The information recording medium according to claim 7,
An information recording medium characterized in that the width of the first attribute sub-region and the second attribute sub-region is set to a dimension capable of forming a diffraction grating for visible light. The information recording medium according to any one of claims 3, 6, 7, and 8,
The first identification mark and the second identification mark are marks having one or a plurality of closed regions for presenting information consisting of letters, numbers, symbols, figures, parts thereof, or combinations thereof. An information recording medium characterized by being.