JP2005011489A - Master disk manufacturing method of optical information recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily control the cross sectional shape of a projected and recessed pattern formed on a master disk using heat mode recording. <P>SOLUTION: A recording master disk is used with a base plate 101, a thermosensitive material layer 102 in which states are varied by exposure and at least one recording auxiliary layer 103 which is arranged to contact the thermosensitive material layer 102. By arbitrarily selecting the thermal conductivity of the recording auxiliary layer, optical constants and thickness or the like, the exposure condition of the thermosensitive material layer is thermally and optically controlled and the cross sectional shape of the projected and recessed pattern formed on the master disk is controlled. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to the manufacture of an optical information recording medium master using heat mode recording in order to form an uneven pattern on the recording master.

  A conventional optical disc recording method and stamper manufacturing method will be described with reference to FIG. First, a photoresist 1002 is formed in a thin film on a substrate 1001 to produce a recording master 1003. A desired pattern such as a guide groove and an information pit is formed as a latent image 1004 by exposing the recording master 1003 with a laser beam or an electron beam (recording beam) 1010 (FIG. 10A). Etching is performed on the recording master after exposure to manufacture a master 1005 in which a desired pattern recorded as a latent image 1004 is formed as a convex or concave (FIG. 10B). In the production of a master for a DVD and its next-generation optical information recording medium, exposure with an ultraviolet laser and wet etching with an alkaline solution are widely used. Formation of a latent image using a photochemical reaction by exposure of a photoresist is also called photon mode recording. The stamper forms a conductive film 1006 on the master 1005 (FIG. 10C), forms a metal layer 1007 on the surface of the conductive film 1006 by plating (FIG. 10D), and peels off the metal layer 1007. Further, it can be obtained by punching or the like. The disk substrate of the optical information recording medium is manufactured by injection molding using a stamper. 10A to 10D show a method of manufacturing a master using a positive type photoresist. In the case of using a negative photoresist, the same method as that described with the positive photoresist is applied except that the unevenness formed on the master is reversed (FIG. 10E). Can be manufactured.

  A method of manufacturing a master by forming a layer made of a heat-sensitive material on the substrate 1001 instead of the photoresist and recording the heat-sensitive material layer in a heat mode has also been proposed (see, for example, Patent Document 1). Heat mode recording refers to a method of recording a predetermined pattern using a change in the state of a substance caused by a temperature change due to exposure. Here, the “state change” of a substance means a change in physical and / or chemical properties of the substance. In the production of the master disc of the optical information recording medium, the heat mode recording is performed in order to form a concave portion (or a convex portion after etching) by etching. In the case of using heat mode recording, a pattern with clearer contours can be obtained as compared with the case of performing photon mode recording using light of the same wavelength. This is because the change in state of the heat-sensitive material due to exposure occurs when the material reaches a certain temperature or higher, and no change in state occurs even if the temperature is raised in a portion where the temperature does not reach the certain temperature. Therefore, a finer pattern can be formed by using heat mode recording. Note that a rewritable optical information recording medium already exists as a product using heat mode recording. In the rewritable optical information recording medium, information recording (that is, pit formation) is performed by utilizing a change in the optical constant of the recording layer caused by a temperature change.

JP-A-10-97738

  As described above, by using the heat mode recording, it is possible to form a concavo-convex pattern with a clear contour on the master surface. However, as shown in FIG. 11 described later, the recess formed using heat mode recording has a cross-sectional shape in which the side surface of the recess is gently inclined, that is, the inclination angle 1104 tends to be small. When a stamper is manufactured using a master having a recess having a small inclination angle (specifically, a guide groove and a signal pit), and the optical information recording medium is manufactured using the stamper, the optical information recording medium is guided. There is an inconvenience that the amplitude of the signal from the groove and the signal pit becomes small.

  In addition, the concave / convex pattern formed on the master disc of the optical information recording medium is transferred when the metal stamper is manufactured and resin-molded, and finally forms a guide groove, a signal pit, and the like in the optical information recording medium. Therefore, in order to form a desired guide groove or the like, it is important to form an optimum inclination angle 1104 on the master according to the transfer process used. However, it is difficult to freely control the tilt angle not only in the heat mode recording but also in the master recording of the optical information recording medium using the photon mode recording.

  The present invention has been made in view of the above circumstances, and has an object of forming a concave portion or a convex portion having a larger inclination angle by using heat mode recording, and further freely controlling the inclination angle. For the purpose.

  The knowledge obtained by the present inventor about the reason why the inclination angle of the concavo-convex pattern becomes small in the master disc of the optical information recording medium manufactured using heat mode recording will be described with reference to FIG. When the heat mode recording is applied to the master recording of the optical information recording medium, one main surface of the heat-sensitive material layer 1101 made of a heat-sensitive recording material is in contact with the atmosphere 1102 and the other main surface is in contact with the substrate 1103. Generally, since the thermal conductivity is different between the atmosphere and a solid substrate, the degree of temperature rise of the heat-sensitive material due to exposure differs between the atmosphere side and the substrate side. That is, in the example shown in FIG. 11, heat is more likely to accumulate near the surface of the heat-sensitive material layer 1101, and a portion whose state changes due to temperature rise is unevenly distributed near the surface of the heat-sensitive material layer 1101. As a result, the change in the surface direction of the ratio of the thickness of the heat-sensitive material layer after etching to the thickness of the heat-sensitive material layer before etching in the concave portion (that is, the slope of the boundary between the portion where the state has not changed and the portion where the state has changed) ) Becomes smaller. As a result, the inclination angle 1104 of the recess is reduced. Here, the inclination angle of the concave portion is an angle formed by a tangent to the side surface of the concave portion at a half of the depth of the concave portion and a plane parallel to the main surface of the master, and a portion remaining after etching. The angle measured on the side of Further, the degree of temperature rise of the heat-sensitive material layer is also affected by the ability of the heat-sensitive material to absorb light having a wavelength used for exposure (that is, light absorption rate), and such light absorption rate is also affected by the heat-sensitive material layer. Varies depending on the material in contact with both major surfaces. The inventor of the present invention is based on the idea that irregularities having a desired cross-sectional shape can be obtained by adjusting the thermal conductivity and / or optical constants of substances (including air) in contact with both main surfaces of the heat-sensitive material layer. Thus, the present invention has been completed.

  The present invention includes a substrate, a heat-sensitive material layer made of a material whose state changes due to a temperature change due to exposure, and a recording auxiliary layer made of a material different from the heat-sensitive material layer as a first optical information recording medium master manufacturing method. The recording material is exposed to the heat-sensitive material layer to form a state-changed portion, and the first etching is performed under conditions where the etching rate of the state-changed portion is different from the etching rate of the non-state-changed portion. A method for manufacturing a master disc of an optical information recording medium is provided. The method of the present invention is characterized by using a recording master in which a recording auxiliary layer having a thermal and / or optical action is provided on the heat-sensitive material layer. According to such a feature, even when a concavo-convex pattern is formed using heat mode recording, it is possible to form a concavo-convex pattern having an unprecedented sharp cross-sectional shape. Further, the cross-sectional shape of the concavo-convex pattern can be easily controlled by appropriately selecting the material and thickness of the recording auxiliary layer. The recording auxiliary layer is preferably provided so as to be in contact with the main surface of the heat-sensitive material layer.

  As described above, the heat-sensitive material is a material whose state changes due to a temperature change (specifically, a temperature increase) due to exposure. Here, “change in state” means that the chemical and / or physical properties of the heat-sensitive material change. The “state-changed portion” is, for example, a phase-changed portion or a thermally crosslinked portion. In this specification, “exposure” is used to mean not only light irradiation but also electron beam irradiation. Further, in this specification, “cross-sectional shape” refers to the shape of a cross section in the thickness direction unless otherwise specified, and “surface” refers to a wide surface perpendicular to the thickness direction (unless otherwise specified) ( Note that it refers to the main surface). Furthermore, in the present specification including the following description, the master of the optical information recording medium may be simply referred to as “master”, and the state-changed portion in the heat-sensitive material layer is formed in a predetermined manner by exposure. May be referred to as “recording”.

  The present invention also provides the first master production method as a second master production method, wherein the recording auxiliary layer is disposed between the heat-sensitive material layer and the substrate in the recording master. A featured method is provided. In that case, the thermal material layer can be controlled thermally and / or optically from the substrate side during recording.

  The present invention provides the first or second manufacturing method as a third master manufacturing method, wherein the material constituting the recording auxiliary layer has a thermal conductivity of the material constituting the substrate in the recording master. A method is provided that is different from thermal conductivity. By changing the material and thickness of the recording auxiliary layer in consideration of the thermal conductivity of the material constituting the substrate, it is possible to easily control the heat dissipation on the substrate side of the heat sensitive material layer, thereby making the recording master It is possible to control the cross-sectional shape and recording sensitivity of the concavo-convex pattern formed on the recording medium.

  The present invention provides the above-described second or third manufacturing method as a fourth master production method, wherein the recording auxiliary layer has light of the heat-sensitive material layer in light having a wavelength used for exposure. A method is provided that is shaped to increase the absorption rate. Such a recording master is specifically formed by appropriately selecting the optical constants (n + iκ, n: refractive index, κ: extinction coefficient) of the recording auxiliary layer according to the optical constants of the substrate and the heat-sensitive material. can do. According to such a recording master, the recording sensitivity of the heat-sensitive material layer during recording can be increased. Further, the distribution of the recording light absorption amount in the depth direction of the heat-sensitive material layer can be controlled, whereby the cross-sectional shape of the concavo-convex pattern can also be controlled.

  The present invention provides a first master manufacturing method as a fifth master manufacturing method, wherein the thermosensitive material layer is located between the recording auxiliary layer and the substrate in the recording master. provide. The recording master used in the fifth method has a configuration in which the recording auxiliary layer is located on the upper surface of the heat-sensitive material layer when the surface of the heat-sensitive material layer close to the substrate is the lower surface. When this recording master is used, the heat-sensitive material layer can be thermally and / or optically controlled from the exposed surface side of the recording master during recording.

  The present invention provides, as a sixth master production method, the fifth master production method, wherein the recording auxiliary layer of the recording master is removed during the first etching. To do. In this method, the materials for the recording auxiliary layer and the heat-sensitive material layer and the etching solution are selected so that the first etching can be performed under such conditions. According to the sixth method, it is not necessary to remove the recording auxiliary layer before performing the first etching, and it is possible to reduce the number of steps of master production.

  The present invention provides the fifth or sixth master manufacturing method as a seventh master manufacturing method, wherein the recording master has a thermal conductivity of the surface of the recording master that is the material constituting the recording auxiliary layer. A method is provided that is different from the thermal conductivity of the medium in contact therewith. The seventh method is a preferable mode in the case of using a recording master in which the recording auxiliary layer is positioned on the heat sensitive material layer. By changing the material and thickness of the recording auxiliary layer based on the thermal conductivity of the external medium of the recording master, it is possible to easily control the heat dissipation on the exposed surface side of the recording master of the thermosensitive material layer. This makes it possible to control the cross-sectional shape and recording sensitivity of the concavo-convex pattern.

  The present invention provides the first optical information recording medium master manufacturing method of the present invention as an eighth master manufacturing method, wherein the recording auxiliary layer includes a first recording auxiliary layer and a second recording auxiliary layer. A recording auxiliary layer, the first recording auxiliary layer is disposed between the thermal material layer and the substrate, and the thermal material layer is disposed between the first recording auxiliary layer and the second recording auxiliary layer. To provide a method characterized by: By using a recording master disk in which two recording auxiliary layers sandwich the heat sensitive material layer, the thermal material layer is separated from both the substrate side and the exposure surface side of the recording master disk during recording. Can be controlled automatically.

  The present invention is the ninth optical disk recording method of the present invention as the ninth optical disk manufacturing method, wherein the thermal conductivity of the material constituting the first recording auxiliary layer is the recording original disk. Is different from the thermal conductivity of the material constituting the substrate. The effect brought about by the ninth method is the same as the effect brought about by the third method.

  The present invention is the eighth or ninth master disk manufacturing method as a tenth master disk manufacturing method, wherein the recording master disk has a thermal conductivity of the material constituting the second recording auxiliary layer. A method is provided wherein the exposed surface is different from the thermal conductivity of the contacting medium. The effect brought about by the tenth method is the same as the effect brought about by the seventh method.

  The present invention is the eleventh master disk manufacturing method according to any one of the eighth to tenth master disk manufacturing method, wherein the recording auxiliary layer has a wavelength of light used for exposure in the recording master disk. A method is provided that increases the light absorptance of a heat sensitive material layer. The effect brought about by the eleventh method is the same as the effect brought about by the fifth method.

  The present invention provides, as a twelfth master production method, any one of the first to eleventh master production methods, wherein the metal reflective layer includes the heat-sensitive material layer and the recording auxiliary layer. Provided is a method characterized by being disposed at a position closer to the substrate than any of the above. In the recording master disk used in the twelfth method, when the position farther from the exposed surface of the recording master disk is defined as lower, the metal reflective layer is formed by either the heat sensitive material layer or the recording auxiliary layer. Is also located below. By providing the metal reflection layer, the light absorption rate of the heat-sensitive material layer during recording can be increased.

  The present invention is the twelfth master manufacturing method of the present invention as a thirteenth master manufacturing method, wherein the recording auxiliary layer is disposed between the metal reflective layer and the heat-sensitive material layer in the recording master. A method is provided in which the thermal conductivity of the material constituting the recording auxiliary layer is smaller than the thermal conductivity of the material constituting the metal reflective layer. Since the metal reflective layer generally has a high thermal conductivity, when it is in contact with the heat sensitive material layer, the heat dissipation of the heat sensitive material layer is increased. In the thirteenth master manufacturing method, it is possible to suppress the heat dissipation property of the heat-sensitive material layer from being increased due to the metal reflection layer by the recording auxiliary layer having a low thermal conductivity.

  The present invention provides the above-described first, second, third, fourth, eighth, ninth, tenth, eleventh, twelfth or thirteenth master manufacturing method as the fourteenth master manufacturing method, wherein the first etching is the heat sensitive method. The method is carried out under a condition that the etching rate of the recording auxiliary layer is lower than the etching rate of the higher etching rate of the portion of the material layer where the state has changed and the portion where the state has not changed. I will provide a. The fourteenth manufacturing method is carried out when a recording master disk in which the recording auxiliary layer is located between the heat-sensitive material layer and the substrate is used. In the fourteenth master production method, it is possible to suppress the surface of the recording auxiliary layer from being roughened during the first etching, so that the surface of the bottom portion of the uneven pattern can be made smoother.

  The present invention provides the fifteenth master production method according to the first, second, third, fourth, eighth, ninth, tenth, eleventh, twelfth, thirteenth, or fourteenth master production method according to the first etching. After selectively removing the heat-sensitive material layer, performing a second etching using the heat-sensitive material layer as a mask, and after the second etching, performing a third etching to remove the heat-sensitive material layer A method characterized in that it is implemented is provided. When the uneven pattern is formed by etching the heat-sensitive material layer, the surface of the heat-sensitive material layer may be roughened and a good uneven pattern may not be obtained in the heat-sensitive material layer. According to the fifteenth method, unevenness is formed in the recording auxiliary layer by the second etching, and the smooth surface of the recording auxiliary layer is exposed by the third etching, so that an excellent uneven pattern can be formed.

The present invention is the fifteenth master production method as a sixteenth master production method, wherein the recording master has a configuration in which the recording auxiliary layer is located between the heat-sensitive material layer and the substrate, When the depth at which the recording auxiliary layer is etched by the second etching is d1, and the average thickness of the heat-sensitive material layer before the second etching is d2, the second etching is the heat-sensitive material. A method is provided in which the etching selectivity of the recording auxiliary layer to the layer is performed under a condition greater than d1 / d2. Here, “depth d1” refers to the depth of the deepest portion of the recessed portion after etching, and the average thickness d2 of the heat-sensitive material layer before the second etching is changed by the first etching. When a part becomes a recessed part, it says the average thickness of the part without a recessed part, and when the part from which the state changed becomes a convex part, it says the average height of a convex part. The etching selection ratio corresponds to the etching rate ratio. In the sixteenth method, r _aux / r _heat > d1 / d 2 where r _{aux is} the etching rate of the recording auxiliary layer and r _heat is the etching rate of the _heat sensitive material layer in the second etching. Cost. According to the sixteenth method, the heat-sensitive material layer serving as an etching mask during the second etching does not disappear during the etching, and a good uneven pattern can be formed by the second etching. it can. The sixteenth method can be applied to any recording master having a recording auxiliary layer between the heat-sensitive material layer and the substrate. Therefore, the sixteenth method can also be applied to a recording master having a structure in which the heat-sensitive material layer is located between the first recording auxiliary layer and the second recording auxiliary layer.

  The present invention provides the fifteenth master disk manufacturing method according to the fifteenth or sixteenth master disk manufacturing method, wherein the second etching is disposed at a position close to the recording auxiliary layer and close to the substrate. A method is provided in which the etching selectivity of the recording auxiliary layer to the layer to be formed is performed under a condition of greater than 1. The layer that is in contact with the recording auxiliary layer and is disposed near the substrate is a layer adjacent to the lower surface of the recording auxiliary layer when the direction from the exposure surface of the recording master to the substrate is downward. Such a layer is, for example, the aforementioned metal reflective layer. In the seventeenth method, since the surface of the lower layer of the recording auxiliary layer is suppressed during the second etching, when the surface of the lower layer is exposed during the second etching, A good concavo-convex pattern having a smoother bottom surface is formed.

  The present invention is the eighteenth master disk manufacturing method according to any one of the first to seventeenth master disks, wherein the recording master disk has a refractive index of 1.35 at the wavelength of light used for the exposure. A light transmission layer made of a material of 1.65 or less is disposed at a position farther from the substrate than both the heat-sensitive material layer and the recording auxiliary layer, and the light transmission layer is removed after the exposure. To provide a method. In the eighteenth master manufacturing method, the light transmission layer made of a material having the specific refractive index corresponds to a protective layer in an optical disc for consumer equipment. Therefore, by forming the light transmission layer, it is possible to focus the light on the recording master using an objective lens for consumer equipment that is mass-produced. This makes it possible to use an inexpensive objective lens for consumer equipment for master recording.

The present invention relates to any one of the first to eighteenth master production methods as the nineteenth master production method, wherein the thermal material layer is one or both of Te and Sb in the recording master. 1 or a plurality of elements selected from Au, Pt, Ag and Cu, and O, the recording auxiliary layer includes one or both of ZnS and SiO ₂ , and the exposure is performed using laser light. And providing a method characterized in that the first etching is alkaline etching. In the nineteenth master manufacturing method, it is possible to use an apparatus that is conventionally used to perform the exposure and the first etching. That is, by using a recording master having a thermosensitive material layer and a recording auxiliary layer made of the materials shown here, an apparatus similar to the apparatus used for manufacturing a DVD having a recording capacity of 4.7 GB per layer and a diameter of 12 cm. Can be used to manufacture a master having a recording density five times higher than that of conventional photon mode recording.

  The present invention is the twelfth master manufacturing method according to any one of the first to nineteenth masters, wherein in the recording master, the recording auxiliary layer is made of a resin material. Provide a method. Since the resin material has a lower thermal conductivity than that of the inorganic material, it is preferably used to form a recording auxiliary layer having a low thermal conductivity, for example, when the metal reflective layer and the recording auxiliary layer are in contact with each other. In addition, a material having desired characteristics can be easily obtained by mixing a plurality of resin materials that can be dissolved in the same solvent.

  The present invention is the twenty-first master manufacturing method according to any one of the first to twentieth masters, wherein the recording auxiliary layer is formed by vapor deposition or sputtering in the recording master. A method is provided that comprises an inorganic material. For example, by performing the vapor deposition method or the sputtering method simultaneously using a target formed by mixing a plurality of materials or using a plurality of targets, a recording auxiliary layer is easily formed by mixing a plurality of different inorganic materials. Accordingly, a recording auxiliary layer having desired characteristics can be easily obtained.

  The present invention is the first to the twenty-first master manufacturing methods as the twenty-second master manufacturing method, wherein the inclination angle of the concave portion or the convex portion formed on the master by the first etching is 50 degrees or more and 73. Provided is a method characterized in that it is less than or equal to the degree. Here, the inclination angle of the concave portion means an angle formed by a side tangent of the side surface parallel to the main surface of the master on the side of the portion remaining after the etching at a half of the depth of the concave portion. The inclination angle is defined as an angle formed between the tangent of the side surface and the plane parallel to the main surface of the master at the half of the height of the convex portion on the side of the portion remaining after etching. According to the master production method of the present invention, by appropriately selecting the material of the recording auxiliary layer of the recording master, etc., it is difficult to form a concavo-convex pattern with a high inclination angle that has been difficult to form by the conventional master production method using heat mode recording. Can be manufactured on the master, so that the master can be recorded with higher resolution.

  The present invention also provides a stamper manufactured using a master manufactured according to the manufacturing method of the present invention. The stamper is manufactured by forming a conductive film and a metal layer on the surface of the master using a conventional method as described in connection with the prior art.

The present invention also provides an optical information recording medium manufactured using a master manufactured according to the manufacturing method of the present invention or a stamper manufactured from the master. The optical information recording medium is, for example, a next-generation optical disc or the like that records using a DVD and a short-wavelength laser beam.
The optical information recording medium may be read-only, or may be recorded only once, or may be rewritable.

  If the method for producing a master of an optical information recording medium of the present invention is used, the cross-sectional shape of the concavo-convex pattern formed on the master can be easily controlled. In addition, the production method of the present invention improves the recording sensitivity when recording on the recording master by appropriately selecting the material and structure of the recording master, and expands the choice of heat-sensitive materials used for heat mode recording. In addition, it is possible to perform master recording using an inexpensive objective lens.

BEST MODE FOR CARRYING OUT THE INVENTION

  Embodiments of the present invention will be described with reference to the drawings. Unless otherwise specified, the term “below” with respect to a certain layer is used to indicate a direction close to the substrate when the recording master is disposed so that the substrate is on the bottom.

(Embodiment 1)
As a first embodiment, a method of manufacturing an optical information recording medium master using a recording master having a recording auxiliary layer positioned between a heat-sensitive material layer and a substrate will be described with reference to FIGS. . FIG. 1A shows a cross section of an example of a recording master. In the recording master 104 shown in FIG. 1A, the substrate 101 is made of glass, silicon, resin, or the like. A recording auxiliary layer 102 made of, for example, a dielectric or resin is formed on the substrate 101 by, for example, a sputtering method or a spin coating method. A heat-sensitive material layer 103 is formed on the recording auxiliary layer 102 so as to be in contact with the recording auxiliary layer 102. The heat-sensitive material layer 103 is made of a material that changes its state by a temperature rise due to exposure, and is formed by, for example, a sputtering method or a spin coating method. The recording master shown in the drawing corresponds to a configuration that is minimally required to carry out the manufacturing method of the first embodiment. Therefore, as long as the recording auxiliary layer is located below the heat sensitive material layer and the cross-sectional shape of the portion whose state has been changed by the recording auxiliary layer can be controlled, for example, the recording master layer includes the recording auxiliary layer and the heat sensitive material layer. Components not shown in the figure may be included such as an interfacial layer positioned between them (for example, a thin layer having a thickness of less than 1 nm), or a reflective layer. An example of the recording master 104 including the metal reflective layer 107 is shown in FIG.

  FIGS. 1B to 1H show a recording master in which a portion 105 whose state has changed due to an increase in temperature is formed on the heat-sensitive material layer 103 by irradiating the recording master with light. Here, a portion where the state has not changed is indicated by reference numeral 106. Here, a recording method on the recording master 104 will be described with reference to FIG. The recording master 201 is placed on the turntable 202 and rotated together with the turntable 202. The recording light 206 emitted from the light source 203 is condensed on the surface of the recording master 201 by the lens 204. If necessary, the recording light 206 may be modulated and / or deflected in the light source 203. During the recording, the recording head 205 and the turntable 202 move relatively in parallel, and recording is performed so that the portions whose state changes in a spiral shape are sequentially formed on the recording master. As the recording light 206, a laser beam or an electron beam bundle can be used. This master recording method using an apparatus as shown in FIG. 2 has been conventionally employed and is not novel in itself, so detailed description thereof will be omitted. Further, any master recording method other than that described here may be used as long as it is a method for recording a desired pattern by utilizing the state change of the heat-sensitive material layer 103 due to temperature rise. Good.

  FIGS. 1B to 1D show portions where the state of the heat-sensitive material layer 103 is changed when the recording auxiliary layer 102 is formed using a material having a different thermal conductivity with the recording auxiliary layer 102 having a constant thickness. The cross-sectional shape of 105 is schematically shown. The thermal conductivity of the material constituting the recording auxiliary layer 102 is high in the order of FIG. 1 (B)> FIG. 1 (C)> FIG. 1 (D). 1B to 1D, it can be seen that the cross-sectional shape of the state-changed portion 105 changes depending on the thermal conductivity of the material constituting the recording auxiliary layer 102. In the recording master in which the recording auxiliary layer is located between the heat sensitive material layer and the substrate, if only the thermal conductivity of the material constituting the recording auxiliary layer is changed, the smaller the thermal conductivity, the more the substrate side surface of the heat sensitive material layer. The amount of heat released from the battery becomes smaller. That is, as the thermal conductivity of the recording auxiliary layer is smaller, it becomes possible to raise the temperature of the deeper part from the surface of the heat-sensitive material layer. Therefore, as shown in FIG. The boundary with the part that has not been made has a steeper slope.

  FIGS. 1E and 1F show heat sensitivity by changing the thickness of the recording auxiliary layer 102 when the recording auxiliary layer 102 is formed of a material whose thermal conductivity is lower than that of the material constituting the substrate 101. It schematically shows how the cross-sectional shape of the portion 105 of the material layer 103 whose state has changed changes. In the recording master shown in FIG. 1 (E), since the recording auxiliary layer 102 is thicker, the heat release from the heat-sensitive material layer 103 is further suppressed, and the state has not changed and the state has not changed. The slope of the boundary between the parts becomes larger. FIGS. 1G and 1H show a state in which the thickness of the recording auxiliary layer 102 is changed when the recording auxiliary layer 102 is formed of a material whose thermal conductivity is higher than that of the material constituting the substrate 101. It shows schematically how the changed portion 105 changes. By making the thermal conductivity of the recording auxiliary layer 102 larger than the thermal conductivity of the substrate 101, the slope of the boundary between the state-changed portion and the portion where the state has not changed is compared with the case where the recording auxiliary layer is not provided. Becomes more gradual. Further, the greater the thickness of the recording auxiliary layer 102, the smaller the slope of the boundary between the part that has changed state and the part that has not changed state. As shown in FIGS. 1E to 1H, it can be seen that the distribution of the portion 105 whose state has changed due to the temperature rise during recording can also be changed by changing the thickness of the recording auxiliary layer 102. 1B to 1H are schematic diagrams showing the tendency of how the thermal conductivity and thickness of the recording auxiliary layer affect the cross-sectional shape of the state-changed portion of the heat-sensitive material layer. Note that there are. The cross-sectional shape actually obtained is the specific value of the thermal conductivity of the material composing the substrate, the difference between this value and the specific value of the thermal conductivity of the material composing the recording auxiliary layer, the actual recording auxiliary layer It is determined by the thickness etc.

  After forming the state-changed portion 105, the recording master disk 104 is subjected to first etching. The first etching is performed under conditions where the etching rate differs between the portion 105 whose state has changed due to the temperature rise during recording and the portion 106 whose state has not changed. Examples of the first etching include dry etching such as reactive ion etching and wet etching using acid or alkali. However, the specific method of the first etching is not limited to these methods, and any method can be used as long as the etching rate can be changed under the condition that the portion 105 where the state has changed and the portion 106 where the state has not changed. May be used.

  FIG. 3 shows a recording master before etching and a master obtained after etching. 3A and 3B show a recording master before etching. 3 (C) and 3 (D) show the condition that the recording master shown in FIGS. 3 (A) and 3 (B) is higher than the etching rate of the portion 106 where the etching rate of the portion 105 whose state has changed is not in the state. The master which is obtained by carrying out etching is shown. In this case, the state-changed portion 105 forms a recess in the master. The inclination angle of the recess corresponds to an angle represented by 301. As described above, the inclination angle of the concave portion is such that the tangent line k of the side surface of the concave portion at half the depth t of the concave portion and the surface p parallel to the main surface of the master remain on the side of the portion remaining after etching. The angle made by Therefore, as shown in FIG. 3C, when the concave portion has a funnel shape spreading toward the master surface, the inclination angle becomes an acute angle. 3 (E) and 3 (F), the recording rate of the recording master shown in FIGS. 3 (A) and 3 (B) is lower than the etching rate of the portion 106 where the state change portion 105 does not change. The master disk obtained by carrying out etching under conditions is shown. In this case, the state-changed portion 105 forms a convex portion on the master. The inclination angle of the convex portion corresponds to an angle represented by 302. As described above, the tangent line j of the side surface of the convex portion at the half of the height h of the convex portion and the surface p parallel to the main surface of the master remain after the etching. The angle made on the part side. Therefore, as shown in FIG. 3 (F), when the convex portion has a conical shape with an area increasing toward the lower side, the inclination angle becomes an acute angle. As shown in FIG. 3, it is possible to create a master in which the portion 105 whose state has changed by etching is formed as a concave or convex shape as it is.

  The first etching is preferably performed under the condition that the etching rate of the recording auxiliary layer 102 is lower than the higher one of the portion 105 where the state has changed and the portion 106 where the state has not changed. That is, as shown in FIGS. 3C and 3D, when the state-changed portion is formed into a recess by etching, it is preferable that the etching rate of the recording auxiliary layer is lower than the etching rate of the state-changed portion. As shown in FIGS. 3E and 3F, when the portion where the state has changed is a convex portion, the etching rate of the recording auxiliary layer is preferably lower than the etching rate of the portion where the state has not changed. The reason why it is desirable for the etching rate of the recording auxiliary layer to be low is that, first, the bottom surface of the recess (generally, the exposed surface of the recording auxiliary layer) becomes flatter in the concavo-convex pattern formed by etching. When the bottom surface of the concave portion is flat, a signal with a small noise component can be obtained when the concave / convex pattern is optically reproduced on an optical information recording medium manufactured from the master or a stamper obtained by transferring the master. Secondly, the smaller the etching amount of the recording auxiliary layer 102 in the first etching, the more faithful uneven pattern can be formed by etching in the pattern created as a latent image during recording. is there. This makes it possible to more effectively control the cross-sectional shape of the concavo-convex pattern based on the present invention. Therefore, in the first etching, the etching rate of the recording auxiliary layer is preferably lower (that is, the lowest) than the etching rate of the portion where the state has changed and the portion where the state has not changed. Good. FIG. 3 shown as the first embodiment shows an example in which the etching rate of the recording auxiliary layer 102 is substantially zero. In the present invention, the etching rate of the recording auxiliary layer 102 in the first etching is It should be noted that forms greater than zero are also included.

  As described above, the method of the present invention makes it possible to control the cross-sectional shape of the concavo-convex pattern finally formed on the master by selecting the thermal conductivity and thickness of the recording auxiliary layer. The inclination angle described above can be used as a parameter representing the cross-sectional shape. Whether the pattern formed by recording (which may be simply referred to as “recording pattern”) is formed as a concave or a convex, if the inclination angle is 90 degrees, a finer recording pattern can be obtained. It is easy to form stably, and the signal characteristics of the optical information recording medium manufactured from the master can be made good. When the stamper is further created from the master, the inclination angle is preferably smaller than 90 degrees on condition that it is larger than 0 degrees, and more preferably 50 degrees to 73 degrees. When the inclination angle is less than 90 degrees, there is an advantage that the uneven pattern transfer from the master to the stamper and the uneven pattern transfer from the stamper to the resin substrate are facilitated. However, the numerical range given here is general, and the optimum value of the inclination angle depends on the subsequent process performed using the master and the usage of the optical information recording medium finally created. Note that it is different. Regardless of the desired inclination angle, if the method of the present invention is used, the inclination angle can be easily controlled by the recording auxiliary layer without changing a heat-sensitive material with few material options. . In addition, it is possible to obtain a concave portion or a convex portion having a larger inclination angle as compared with the master recording in the conventional heat mode.

  The first embodiment also improves the recording sensitivity of the heat-sensitive material layer 103 and makes it possible to realize various master disk configurations. For example, when the thermal conductivity of the recording auxiliary layer 102 is smaller than that of the substrate 101, by providing the recording auxiliary layer 102, not only can the cross-sectional shape of the state-changed portion 105 be changed, but also at the time of recording. Sensitivity can also be improved. More specifically, a layer that acts to increase the absorptance of light having a wavelength used for exposure of the heat-sensitive material layer by providing the recording auxiliary layer preferably adjacent to the lower side of the heat-sensitive material layer. Can be arranged below the heat-sensitive material layer. For example, such an optical effect can be obtained by using the substrate 101 as a silicon substrate. Since the silicon substrate has a thermal conductivity that is two orders of magnitude higher than that of general glass or resin, it is difficult to perform heat mode recording on a master disk in which the heat-sensitive material layer and the silicon substrate are in contact with each other. In the method of the present invention, if the recording auxiliary layer is formed of a material having a low thermal conductivity, a recording master can be manufactured using this silicon substrate. The silicon substrate is also preferably used because it is clean. It is also possible to use a substrate having a high thermal conductivity other than the silicon substrate as required. Alternatively, in order to improve the recording sensitivity of the thermosensitive material layer, Au, Ag, Al, Cu, Pt, Pd, Cr are interposed between the substrate 101 and the recording auxiliary layer 102 as shown in FIG. It is also easy to provide the metal reflective layer 107 having a very high thermal conductivity made of one or more elements selected from metal elements such as Ni, a mixture or a compound thereof.

  Further, it is possible to increase the light absorption rate of the heat-sensitive material layer 103 by appropriately selecting the optical constants of the materials constituting the recording auxiliary layer 102 and the thickness of the recording auxiliary layer 102. The optical constant is appropriately selected, for example, by appropriately adjusting the refractive index of the material constituting the recording auxiliary layer 102 at the wavelength of light used for recording. An appropriate optical constant of the recording auxiliary layer is determined in consideration of optical effects (for example, reflection and interference effects) between the substrate 101, the recording auxiliary layer 102, and the heat-sensitive material layer 103. Further, considering the optical effect of each layer constituting the recording master, by configuring the recording master so that the combination of optical constants of each layer is appropriate, the light absorption rate of the heat-sensitive material layer 103 can be reduced in the depth direction. It is also possible to control the cross-sectional shape of the uneven pattern formed on the master.

  A specific example of controlling the cross-sectional shape of the concavo-convex pattern formed on the master according to the method of the present invention will be described with reference to FIG. FIGS. 4A and 4B each show a recording master before exposure. Here, an example in which a soda glass substrate is used as the substrate 401 will be described. Examples of the substrate 401 material other than soda glass include quartz glass, silicon, polycarbonate resin, acrylic resin, and olefin resin. As the material of the substrate 401, any material can be used as long as it can form a flat plate. Here, the thickness of the substrate 401 is 6.0 mm. The thickness of the board | substrate 401 is not limited to this, For example, it selects from the range of 0.4-10.0 mm. Since the optical effect provided by the recording auxiliary layer 403 varies depending on the optical constant of the substrate, it may be preferable to change the thickness of the recording auxiliary layer from the following values in consideration of this.

The heat sensitive material layer 402 was formed of a material represented by TeO _1.0 Pd _3.0 by a sputtering method. The thickness was 45 nm. Instead of Te, Sb, Se, Sn, Ge, Mo, W, Ti, or the like can also be used. Further, instead of Pd, other metal elements, for example, noble metals such as Au, Ag, Cu or Pd may be used. By forming a heat-sensitive material layer with a material containing these noble metals, the remaining film ratio during etching (if the part whose state has changed becomes a concave part, the unexposed part (that is, the part whose state has not changed) The ratio of the thickness after etching to the thickness before etching) can be increased. A material suitable for forming the heat-sensitive material layer 402 is a general formula, M ¹ _X OM ² _Y (where M ¹ is selected from Te, Sb, Se, Sn, Ge, Mo, W, and Ti). One or a plurality of metals, M ² is a metal element other than M ¹ , preferably one or a plurality of elements selected from Au, Ag, Cu and Pd, and 0.3 <X <1. 7, 0.05 <Y <0.52. However, the material constituting the heat-sensitive material layer 402 may be a material not represented by this formula. Further, the thickness of the heat-sensitive material layer 402 can also be changed according to the uneven pattern to be formed on the master.

In the recording master shown in FIG. 4A, the recording auxiliary layer 403a is a layer formed by sputtering and containing ZnS and SiO ₂ at a molar ratio of 4: 1 and has a thickness of 45 nm. is there. In the recording master shown in FIG. 4B, the recording auxiliary layer 403b is a layer made of SiO ₂ formed by sputtering and has a thickness of 45 nm. The thicknesses of the recording auxiliary layers 403a and 403b are not limited to 45 nm, and depend on the material and thickness of the thermal material layer 402 so that the light absorption rate at the recording wavelength of the thermal material layer 402 is maximized. Selection is preferable in order to increase recording sensitivity. For example, when the thermosensitive material layer 402a is formed to have a thickness of 60 nm without changing the material, the recording sensitivity is maximized when the thickness of the auxiliary recording layer 403a is 35 nm.

  These two recording masters were exposed using a laser beam with a wavelength of 405 nm and an objective lens with NA of 0.9 so that the pattern corresponding to the pit row and the guide groove was formed as a state-changed portion. Next, wet etching with 1.7% TMAH (tetramethylammonium hydroxide) was performed for 60 seconds. As a result, the masters shown in FIGS. 4C and 4D were obtained from the recording masters shown in FIGS. 4A and 4B, respectively. The etching solution used here is an example, and the concentration of TMAH can be selected from a range of 1.0% to 2.4%, for example. Alternatively, instead of TMAH, for example, other alkaline aqueous solutions such as KOH and NaOH can also be used for etching. As a result of the etching, the changed state became concave, and a circular pit with a diameter of 90 nm and a guide groove with a width of 70 nm were stably formed on the master. The formation of such recesses means that a resolution sufficient to manufacture an optical information recording medium having a diameter of 12 cm and a recording capacity of 25 GB or more per layer has been achieved.

  The inclination angle 404 of the recess formed on the master was 73 degrees in the master shown in FIG. 4C and 28 degrees in the master shown in FIG. 4D. Further, the sensitivity during recording was higher for the recording master shown in FIG. 4 (A) than that shown in FIG. 4 (B), and the former was about twice the latter. For these reasons, the recording master disk on which the recording auxiliary layer 403 is formed according to the method of the present invention is used, and further, for example, by changing the composition ratio of the material of the recording auxiliary layer, the inclination of the cross-sectional shape of the recesses formed in the master disk It can be seen that the angle 404 can be controlled to an arbitrary value, for example, from 28 degrees to 73 degrees, and the recording sensitivity can be controlled by, for example, about twice the width. Furthermore, according to the method of the present invention, it has been difficult to realize in a master disk recorded in heat mode using a recording master disk in which only a heat-sensitive material layer is arranged on a substrate made of quartz glass or soda glass according to a conventional method. It can also be seen that a high tilt angle of 50 degrees or more can be realized.

Here, the method of the present invention has been described using an example in which the recording auxiliary layer is formed by changing the composition ratio of ZnS and SiO ₂ . The material constituting the recording auxiliary layer is not limited to these. The recording auxiliary layer includes, for example, selenide such as ZnSe, Si—O, Ge—O, Al—O, Zn—O, Y—O, La—O, Ti—O, Zr—O, Hf—O, Nb. -O, Ta-O, Cr-O, Mo-O, W-O, Sn-O, In-O, Sb-O, Bi-O and other oxides, Si-N, Ge-N, Al- N, Zn—N, Ti—N, Zr—N, Hf—N, Nb—N, Ta—N, Cr—N, Mo—N, W—N, Sn—N, and nitrides such as In—N , Si—O—N, Ge—O—N, Al—O—N, Ti—O—N, Zr—O—N, Hf—O—N, Nb—O—N, Ta—O—N, Cr Nitrogen oxides such as —O—N, Mo—O—N, W—O—N, Sn—O—N, and In—O—N, Ge—C, Cr—C, Si—C, Al—C Ti-C, Zr-C, Ta-C, etc. Carbide, Si-F, Al-F , Mg-F, Ca-F, and fluorides such as LaF, and one or more materials selected from the group consisting of ZnS and SiO ₂ exemplified above or, You may form those mixed materials by forming into a film using a sputtering method or a vapor deposition method.

  Alternatively, the recording auxiliary layer may be formed of an organic material, for example, a layer made of an acrylic resin, an epoxy resin, or a mixture thereof. The recording auxiliary layer made of a resin material is formed, for example, by a method of forming a film by spin coating. Furthermore, even when a resin material is used, it is possible to control the cross-sectional shape of the concavo-convex pattern by controlling the thermal conductivity and optical constant of the recording auxiliary layer 403 by selecting the mixing ratio or composition ratio. it can. Of course, by using a method other than the method described here and appropriately selecting at least one of the thermal conductivity and the optical constant of the recording auxiliary layer, the cross-sectional shape of the concavo-convex pattern formed on the master (specifically, It is possible to control the inclination angle.

(Embodiment 2)
As Embodiment 2, a method of manufacturing a master using a recording master having a recording auxiliary layer on the upper surface (surface far from the substrate) of the heat-sensitive material layer will be described with reference to FIG. FIG. 5A shows an example of a recording master. The recording master 504 is formed by forming a heat sensitive material layer 502 on a substrate 501 and further forming a recording auxiliary layer 503 on the heat sensitive material layer 502. In FIG. 5A, reference numeral 506 denotes an external medium (that is, an atmosphere during exposure), which is generally air. The material of the substrate 501 and the material and forming method of the heat-sensitive material layer 502 constituting the recording master 504 are as described in connection with the first embodiment. The recording auxiliary layer 503 may be a film formed by the material and method described in connection with the first embodiment. Alternatively, the recording auxiliary layer 503 may be a liquid. Specifically, the second embodiment is also performed by performing exposure in a state where a liquid to be the recording auxiliary layer 503 is disposed (for example, applied) or in a state where the recording master is immersed in the liquid. can do. The recording master shown in the drawing corresponds to a configuration that is minimally required to carry out the manufacturing method of the second embodiment. Therefore, as long as the recording master has a configuration in which the heat-sensitive material layer is positioned between the recording auxiliary layer and the substrate, the recording master may include, for example, components not shown in the figure such as the interface layer or the reflective layer as described above. .

  5B to 5H show a recording master in which a portion 505 whose state has changed due to a temperature rise and a portion 507 whose state has not changed are formed on the heat-sensitive material layer 502 by irradiating the recording master with light. Show. Since the recording method on the recording master is the same as that described in connection with the first embodiment, the description is omitted. FIGS. 5B to 5D show the state-changed portion 505 of the heat-sensitive material layer 502 in the case where the recording auxiliary layer is formed using a material having different thermal conductivity with the recording auxiliary layer 503 having a constant thickness. The cross-sectional shape of is shown typically. The thermal conductivity of the material constituting the recording auxiliary layer 503 is higher in the order of FIG. 5B> FIG. 5C> FIG. 5D. 5B to 5D, it can be seen that the cross-sectional shape of the state-changed portion 505 changes depending on the thermal conductivity of the material constituting the recording auxiliary layer 503. In a recording master in which the recording auxiliary layer is positioned on the heat sensitive material layer, if only the thermal conductivity of the material constituting the recording auxiliary layer is changed, the heat conductivity is smaller, the heat is accumulated near the surface of the heat sensitive material layer. It becomes easy. That is, as the thermal conductivity of the recording auxiliary layer is smaller, it is more difficult to raise the temperature at a deeper portion from the surface of the heat-sensitive material layer. Therefore, as shown in FIG. Will have a more gentle slope.

  FIGS. 5E and 5F show that the thickness of the recording auxiliary layer 503 is changed when the recording auxiliary layer 503 is formed of a material whose thermal conductivity is smaller than that of the external medium 506. It schematically shows how the cross-sectional shape of the portion 505 where the state of the heat-sensitive material layer 502 is changed changes. In the recording master shown in FIG. 5 (E), since the recording auxiliary layer 503 is thicker, heat is further prevented from being released from the surface of the heat-sensitive material layer 502, and the state changes from the state-changed portion. The slope of the boundary between the unexposed parts becomes smaller. FIGS. 5G and 5H show a portion whose state has changed by changing the thickness of the recording auxiliary layer 503 when the recording auxiliary layer 503 is formed of a material having a thermal conductivity larger than that of the external medium 506. It shows schematically how the cross-sectional shape of 505 changes. By making the thermal conductivity of the recording auxiliary layer 503 larger than the thermal conductivity of the external medium 506, the inclination between the portion where the state has changed and the portion where the state has not changed is larger than when the recording auxiliary layer is not provided. Become bigger. Further, the greater the thickness of the recording auxiliary layer 503, the larger the slope of the boundary between the part that has changed state and the part that has not changed state. In general, the external medium 506 to which the heat-sensitive material layer 502 is exposed is air having a very low thermal conductivity compared to a solid or liquid. In that case, since it is generally difficult to make the thermal conductivity of the recording auxiliary layer 503 smaller than that of the external medium, the control of the cross-sectional shape of the state-changed portion is as shown in FIGS. 5 (G) and 5 (H). Realized. However, when a liquid is used as the external medium 506, such as original recording by an LIL (immersion lens method), the state-changed portion 505 is controlled as shown in any of FIGS. Is also feasible. As described above, even when the recording auxiliary layer is provided on the heat-sensitive material layer, the distribution of the portion 505 whose state has changed due to the temperature rise during recording can be changed by changing the thickness of the recording auxiliary layer 503. I understand that. Note that FIGS. 5B to 5H are schematic diagrams showing how the thermal conductivity and thickness of the recording auxiliary layer affect the cross-sectional shape of the state-changed portion of the heat-sensitive material layer. Note that it is a figure. The cross-sectional shape actually obtained is the specific value of the thermal conductivity of the external medium, the difference between this value and the specific value of the thermal conductivity of the material constituting the recording auxiliary layer, the actual thickness of the recording auxiliary layer Determined by etc.

  Next, the recording auxiliary layer 503 is removed from the recording master 504 after recording. The removal of the recording auxiliary layer 503 is preferably performed so that the influence on the heat-sensitive material layer 502 is reduced. The main component of the recording auxiliary layer 503 is an organic material such as a novolac resin, an acrylic resin, or a polycarbonate resin, and the main component of the thermal material layer 502 is, for example, Te, Sb, Se, Sn, Ge, or Mo. In the case of an inorganic material such as a compound, for example, wet etching using an organic solvent or plasma etching using oxygen or a rare gas is preferably performed. If these etchings are used, the etching rate of the recording auxiliary layer 503 becomes sufficiently larger than the etching rate of the heat-sensitive material layer 502, and only the recording auxiliary layer 503 can be efficiently removed. If the material constituting the heat-sensitive material layer 502 is not water-soluble, recording can be easily performed by forming the recording auxiliary layer 503 from a water-soluble material such as polyvinyl alcohol, polyethylene oxide, or sodium polyacrylate. Only the auxiliary layer 503 can be removed. If the material constituting the heat-sensitive material layer 502 is not alkali-soluble, forming the recording auxiliary layer 503 with an alkali-soluble material such as a novolak resin or an acrylic resin can easily form only the recording auxiliary layer 503. It can be removed. If the material constituting the heat-sensitive material layer 502 is not acid-soluble, it is possible to easily remove only the recording auxiliary layer 503 if the recording auxiliary layer 503 is formed of an acid-soluble material.

  Next, the first etching is performed under conditions where the etching rate is different between the portion 505 whose state has changed due to the temperature rise during recording and the portion 507 whose state has not changed. Since the example of the first etching is as described in connection with the first embodiment, the description is omitted here. Also in the second embodiment, the first etching is performed under the condition that the etching rate of the substrate 501 is lower than the higher one of the portion 507 where the state has changed and the portion 507 where the state has not changed. It is preferable to implement. The reason for this is the same as that described in the first embodiment, and is omitted here. By this first etching, the region 505 whose state has been changed by the temperature rise during recording is formed as a convex or concave on the master.

  In the above, the embodiment in which the removal of the recording auxiliary layer 503 and the etching of the heat-sensitive material layer 502 are performed as separate processes has been described. Alternatively, the recording auxiliary layer 503 can be removed and the thermal material layer 502 can be etched at the same time. In that case, the possibility of contamination and cost can be reduced by reducing the number of steps. Specifically, for example, the heat-sensitive material layer 502 is made of a Te or Sb compound and the like, and the etching rate at the time of alkaline etching is large between the portion 505 that has changed its state due to the temperature rise during recording and the portion 507 that has not changed. When the recording auxiliary layer 503 is made of an alkali-soluble material such as a novolac resin or an acrylic resin, for example, the recording auxiliary layer 503 is removed and the thermal material layer 502 is simultaneously etched by alkali etching. Can be implemented. Further, when the etching of the heat-sensitive material layer 502 is performed using an acid, the recording auxiliary layer 503 may be formed of an acid-soluble material. When the etching of the heat sensitive material layer 502 is performed using an aqueous solution, if the recording auxiliary layer 503 is formed of a water-soluble material such as polyvinyl alcohol, polyethylene oxide, or sodium polyacrylate, for example, The heat sensitive material layer 502 can be etched and the recording auxiliary layer 503 can be removed by the treatment. There are various other methods. In any case, the recording auxiliary layer 503 can be efficiently removed by performing the etching so that the etching rate of the recording auxiliary layer 503 is larger than the etching rate of the thermal material layer 502. Further, when the removal of the recording auxiliary layer 503 and the etching of the heat sensitive material layer 502 are performed at the same time, the etching rate of the recording auxiliary layer 503 is the etching rate of the portion 505 that has changed state and the portion 507 that has not changed state. It is preferable that it is higher than the lower one. Thereby, the degree of surface roughness of the portion remaining in the heat-sensitive material layer after etching (that is, the lower of the etching rates of the portion 505 that has changed state and the portion 507 that has not changed state) can be reduced.

  As described above, if the method of the present invention described in Embodiment 2 is used, the cross-sectional shape of the uneven pattern on the master can be easily controlled without changing the material of the heat-sensitive material layer.

(Embodiment 3)
As Embodiment 3, a method of manufacturing an optical information recording medium master using a recording master in which two recording auxiliary layers are arranged so as to sandwich a thermosensitive material layer will be described with reference to FIG. FIG. 6A shows an example of a recording master. The recording master 605 has a first recording auxiliary layer 602 formed on a substrate 601, a heat sensitive material layer 603 formed on the first recording auxiliary layer 602, and a second recording auxiliary layer on the heat sensitive material layer 603. Obtained by forming 604. The material of the substrate 601 and the material and forming method of the heat-sensitive material layer 603 constituting the recording master 605 are as described in connection with the first embodiment. The first recording auxiliary layer 602 and the second recording auxiliary layer 604 are also formed by the materials and methods described in connection with the first embodiment. The second recording auxiliary layer 604 may be a liquid as described in connection with the second embodiment. In this case, it is necessary to supply the liquid by coating or dipping during recording. The recording master shown in the drawing corresponds to a configuration that is minimally required to carry out the manufacturing method of the third embodiment. Therefore, as long as the recording master is configured so that the heat-sensitive material layer is sandwiched between the two recording auxiliary layers, for example, an interface layer located between the recording auxiliary layer and the heat-sensitive material layer, or a reflective layer, Components not shown may be included.

  For example, as shown in FIG. 6B, a metal reflective layer 606 may be provided between the substrate 601 and the first recording auxiliary layer 602. The material and forming method of the metal reflective layer 606 are as described in connection with the first embodiment. Also in this embodiment, as described in connection with the first embodiment, the presence of the first recording auxiliary layer 602 reduces the adverse thermal effect caused by the metal reflection layer 606 and provides an optical effect. Can be obtained.

  A desired pattern is recorded on the recording masters 605 and 605a shown in FIGS. 6 (A) and 6 (B). The method is the same as in the first embodiment. Next, the second recording auxiliary layer 604 is removed, and further a first etching is performed to obtain a master on which a concavo-convex pattern is formed. Alternatively, the removal of the second recording auxiliary layer 604 and the first etching may be performed simultaneously. Since both methods are as described above in connection with the third embodiment, they are omitted here.

  In the recording master 605, the first recording auxiliary layer 602 can function in the same manner as the recording auxiliary layer 102 described in the first embodiment, and the second recording auxiliary layer 604 is the recording described in the second embodiment. It can function in the same manner as the auxiliary layer 503. Therefore, by using the recording master 605, the advantages brought about by the first embodiment and the second embodiment can be obtained at the same time, as compared to the case of using the recording master having only one recording auxiliary layer. The cross-sectional shape of the concavo-convex pattern on the master and the sensitivity during recording can be controlled more freely.

(Embodiment 4)
As Embodiment 4, a method of performing second etching after the first etching for forming irregularities in the heat-sensitive material layer will be described with reference to FIG. In the fourth embodiment, using the recording master used in the first or third embodiment, a concavo-convex pattern is formed on the heat-sensitive material layer by the same method as in the first or third embodiment, respectively. . FIG. 7A shows a recording master 704a in which a portion whose state has changed due to a temperature rise during recording of the heat-sensitive material layer 701 is formed as a recess. FIG. 7B shows a temperature rise during recording of the heat-sensitive material layer 701. Each of the recording masters 704b formed with convex portions is shown in a sectional view. In any recording master, the heat-sensitive material layer 701 is formed on the auxiliary recording layer 702. The layer 703 adjacent to the lower surface of the recording auxiliary layer 702 is generally a substrate or a metal reflective layer as described in connection with the first and third embodiments. It is not limited. Hereinafter, the fourth embodiment will be described using a recording master on which a recording pattern in which a state-changed portion shown in FIG.

In the fourth embodiment, the second etching using the heat-sensitive material layer 701 as a mask is performed on the recording master after the first etching. In the second etching, the portion of the heat-sensitive material layer 701 remaining after the first etching acts as a mask, and the portion of the recording auxiliary layer 702 exposed after the first etching is removed to form a recess. The second etching may be reactive ion etching, plasma etching, wet etching with acid or alkali, or the like. The heat-sensitive material layer 701 is formed of an inorganic material that is a compound such as Te, Sb, Se, Sn, Ge, or Mo, and the recording auxiliary layer 702 is formed of an organic substance such as a novolac resin, an acrylic resin, or a polycarbonate resin. In this case, it is preferable that the second etching is plasma etching or wet etching with an organic solvent because it is easy to carry out. Alternatively, the auxiliary recording layer 702 formed of SiO _2, a fluorine-based gas or liquid is also preferably carried out second etching by a method of selectively removing the SiO _2.

  FIG. 7C shows the recording master after the second etching. In FIG. 7C, d1 corresponds to the depth at which the recording auxiliary layer 702 is etched. The second etching is preferably performed so as to prevent the mask from disappearing. When the mask disappears, the portion to be masked of the recording auxiliary layer 702 is etched, so that a desired uneven pattern cannot be formed. Therefore, in the second etching, when the average thickness of the heat-sensitive material layer 701 before the second etching is d2 (see FIG. 7A), the etching selection of the recording auxiliary layer 702 with respect to the heat-sensitive material layer 701 is selected. It is preferable that the ratio be (d1 / d2) or more. When the recording master as shown in FIG. 7B is subjected to the second etching, the convex portion becomes a mask and a concave portion is formed in the recording auxiliary layer 702 (not shown).

Further, as shown in FIG. 7D, when the second etching is performed until the surface of the lower layer 703 is exposed, it is preferable that the etching selection ratio of the recording auxiliary layer 702 to the lower layer 703 is larger than 1. By selecting the etching selectivity in such a manner, the surface of the lower layer 703 exposed by the second etching can be reduced to the extent that the surface is roughened by the second etching. Is obtained. For example, when the recording auxiliary layer 702 includes SiO ₂ and the lower layer 703 is made of Si, the lower layer 703 is exposed by performing reactive ion etching with a fluorine-based material such as fluorocarbon as the second etching, for example. However, surface roughness due to the second etching can be reduced. When the recording auxiliary layer 702 is made of an organic material such as a novolac resin, an acrylic resin, or a polycarbonate resin, and the lower layer 703 is made of an inorganic material such as glass or silicon, plasma etching or wet etching with an organic solvent is used for the second etching. This etching is also preferable when the lower layer 703 is exposed. Further, when the lower layer 703 is the above-described metal reflective layer, the etching selectivity of the recording auxiliary layer 702 with respect to the lower layer 703 can be easily increased. Therefore, a recording master having a structure in which the lower layer 703 is a metal reflective layer is preferably used in the fourth embodiment.

Next, a third etching is performed to remove the heat-sensitive material layer 701 used as a mask to obtain a master. Examples of the third etching include dry etching such as reactive ion etching and plasma etching, and wet etching with acid or alkali. The third etching is preferably performed so that the etching selectivity of the heat-sensitive material layer 701 to the recording auxiliary layer 702 is greater than 1. By selecting the etching selection ratio in such a manner, the degree to which the recording auxiliary layer 702 is etched by the third etching can be lowered, so that a good pattern is formed on the master. When the lower layer 703 is exposed by the second etching, or when the lower layer 703 is exposed by the third etching, the etching selectivity of the heat-sensitive material layer 701 to the lower layer 703 is larger than 1 in the third etching. It is more preferable to carry out such that. This is because the degree of etching of the lower layer 703 by the third etching is lowered to form a good pattern on the master. As an example, heat-sensitive material layer 701 is composed of an oxide of Te, the recording auxiliary layer 702 is made of SiO _2, if the lower layer 703 is made of Si, as the third etching, etching with an alkali such as TMAH or KOH When implemented, the heat-sensitive material layer 701 as a mask can be removed with little damage to the recording auxiliary layer 702 and the lower layer 703.

  According to the method of the fourth embodiment, the surface of the flat recording auxiliary layer is exposed by removing the heat-sensitive material layer, and a favorable uneven pattern can be formed on the recording auxiliary layer. Therefore, in the method of the fourth embodiment, the surface of the heat-sensitive material layer is roughened or scum is generated while the first etching is performed according to the method of the first or third embodiment. This is particularly useful when a good uneven pattern cannot be obtained. Further, in the method of the fourth embodiment, when the master manufactured by the method of the first or third embodiment is further subjected to another process (for example, plating), the material of the heat-sensitive material layer is the other process. It is also preferably used when causing problems. As described above, by using the method according to the fourth embodiment, it is possible to broaden the choice of heat-sensitive materials used for manufacturing an optical information recording medium master by heat mode recording.

(Embodiment 5)
As a fifth embodiment, a method using a recording master in which a light transmission layer is formed on a heat sensitive material layer will be described. FIG. 8A is a sectional view showing the recording master used in the fifth embodiment. The recording master 805 is obtained by forming the recording auxiliary layer 804 on the substrate 801, forming the heat sensitive material layer 802 on the recording auxiliary layer 804, and forming the light transmission layer 803 on the heat sensitive material layer 802. It is done. The material of the substrate 801 constituting the recording master 805, the material of the heat-sensitive material layer 802 and the recording auxiliary layer 804 and the forming method thereof are as described in connection with the first embodiment. A specific material and formation method of the light transmission layer 803 will be described later. The configuration of the recording master 804 shown in the figure is an example of the minimum configuration required for carrying out the manufacturing method of the fifth embodiment. Therefore, as long as the light transmission layer is formed as the uppermost layer, the recording master may include components not shown such as an interface layer or a reflective layer. Further, instead of or together with the recording auxiliary layer 804, a recording auxiliary layer may be formed on the heat-sensitive material layer. In this case, the light transmission layer is formed on the recording auxiliary layer.

  Before describing the material and forming method of the light transmission layer, advantages of forming the light transmission layer will be described with reference to FIG. FIG. 9 shows the structure of a general optical information recording medium 901. An optical information recording medium 901 shown in FIG. 9 includes a substrate 902 onto which an uneven pattern formed on a master is directly or indirectly transferred, at least one signal layer 903 formed on the substrate 902, and A transparent protective layer 904 is formed on the signal layer 903. For example, in the rewritable and write-once recording media, the signal layer 903 includes a layer made of a chalcogen compound or a dye, and a reflective layer made of metal, silicon, or the like is used to improve recording / reproducing characteristics as necessary. Also have. In the read-only optical recording medium, the unevenness formed on the substrate becomes signal information, and the signal layer 903 is a reflection layer provided to read out this signal information as a phase difference of reflected light. In any form of the optical information recording medium 901, reproduction and recording are both performed by light 906 (for example, laser light) collected by the objective lens 905.

  An objective lens 905 used for recording and reproduction of an optical information recording medium is provided at a relatively low cost with the spread of DVDs and CDs. Therefore, if the objective lens 905 can be used for exposure when manufacturing the master, the cost of manufacturing the master can be reduced. However, in the conventional master recording method, the layer on which the recording light is to be collected is disposed on the surface of the recording master, or is covered with a layer that is optically completely different from the protective layer 904 of the optical information recording medium 901. For these reasons, it is impossible to use an objective lens used for reproducing and recording an optical information recording medium for recording a master due to the influence of spherical aberration. Therefore, master recording requires a very expensive objective lens that is manufactured exclusively for master recording.

  The method of the present invention uses a heat-sensitive material capable of heat mode recording as a recording master, thereby recording light having substantially the same wavelength as that of light and an objective lens generally used for reproducing and recording optical information recording media. The master recording can be performed using the NA of the light and the objective lens. That is, the method of the present invention makes it easier to use an objective lens used in consumer equipment for master recording. However, it is difficult to actually use such an objective lens due to the influence of spherical aberration as described above. Therefore, the present inventors considered that such a lens can be used by making the configuration of the master itself the same as that of the optical information recording medium. This is the reason why the light transmission layer 803 is provided. That is, it is an advantage of the method of the fifth embodiment that an inexpensive objective lens mounted on a drive of a consumer device can be used as an objective lens for master recording.

  Therefore, the light transmission layer 803 is formed so as to be a layer having an optical constant and a thickness approximately equal to those of the protective layer 904 of the optical information recording medium. In general, the protective layer 904 of the optical information recording medium is formed of a resin such as a polycarbonate resin. The protective layer 904 has a refractive index of about 1.4 to 1.6 in the vicinity of a wavelength of 405 nm that is to be used for recording and reproduction of the next generation optical information recording medium. Therefore, the light-transmitting layer 803 used in the present invention is also preferably formed of a material having a refractive index of light having a similar wavelength, such as a material having a refractive index of 1.35 or more and 1.65 or less. Specifically, examples of the material constituting the light transmission layer 803 include polycarbonate resin, acrylic resin, quartz glass, and soda glass. However, the material is not limited to these and has the above-described refractive index. Any material can be formed. The thickness of the light transmission layer 803 is selected according to the objective lens to be used. Since it is easier to control the thickness of the light transmitting layer 803 than to control the refractive index thereof, it is preferable to adjust spherical aberration or the like by the thickness of the light transmitting layer 803. Furthermore, when fine adjustment of spherical aberration is desired, a spherical aberration correction mechanism may be provided between the objective lens and the light source.

  The light transmission layer 803 may be formed by applying a liquid material containing a curable resin by spin coating or the like and then curing the curable resin by volatilization of a solvent or irradiation with ultraviolet rays. Alternatively, the light transmission layer 803 may be formed by a method in which a sheet-like transparent material is bonded with an adhesive sheet or an adhesive. Alternatively, the light transmission layer 803 may be formed on the recording master by the method shown in FIGS. 8B to 8D. FIG. 8B shows a method in which a sheet-like material is placed on the surface of a recording master in a vacuum atmosphere 807 and the sheet-like material is bonded to a substrate 801 with an adhesive 806. FIG. 8C shows a method in which the recording master is wrapped with a bag-shaped sheet material, and the sheet and the recording master are brought into close contact with each other by vacuum suction and then sealed. FIG. 8D shows a method for vacuum-sucking a sheet-like transparent material through the opening 808 formed in the substrate and the turntable 202 when the recording master is exposed. The light transmission layer 803 is in close contact with a layer located under the light exposure layer (a heat-sensitive material layer in FIG. 8 and a recording auxiliary layer when a recording auxiliary layer is formed on the heat-sensitive material layer). And need not be bonded to the underlying layer prior to exposure.

  The recording method on the recording master is as described in connection with the first embodiment. After recording, the light transmission layer 803 is removed. For example, when the light transmission layer 803 is formed by curing a liquid material containing a curable resin, the light transmission layer 803 can be removed using a solvent or a plasma etching method or the like. In the case where the light transmission layer 803 is formed by adhering a sheet-like transparent material to the heat-sensitive material layer 802 with an adhesive sheet or an adhesive, for example, an adhesive that is easy to peel off is used for bonding. Then, the sheet-like material may be removed by peeling. In this case, the adhesive residue may be removed using a solvent or by plasma etching or the like. Alternatively, for example, as shown in FIGS. 8B, 8C, and 8D, when the light transmission layer is not fixed to the layer below it (for example, the heat-sensitive material layer 802), peeling or The light transmission layer can be easily removed by releasing the vacuum.

  The processing (specifically, etching) of the recording master after the light transmission layer 803 is removed is performed using the method described in connection with the first to fourth embodiments according to the configuration of the recording master. Thus, a master disc of the optical information recording medium can be obtained.

  The master production method of the present invention makes it possible to form a fine concavo-convex pattern by controlling its cross-sectional shape using heat mode recording. Therefore, an optical information recording medium for recording and / or reproducing a signal using light having a short wavelength such as blue laser light, for example, is required for the master produced by the method to have a fine uneven pattern. Suitable for manufacturing.

1A and 1I are cross-sectional views of an example of a recording master used in the master manufacturing method of the present invention, and FIGS. 1B to 1H are cross-sectional views of the recording master after exposure, respectively. It is. FIG. 2 is a schematic diagram showing an apparatus for performing master recording and a master recording method. FIGS. 3A and 3B are cross-sectional views of the recording master before the first etching, and FIGS. 3C to F are cross-sectional views of the master obtained after the first etching. 4A and 4B are cross-sectional views of the recording master before the first etching, and FIGS. 4C and 4D are cross-sectional views of the master obtained after the first etching. FIG. 5A is a cross-sectional view of another example of a recording master used in the method of manufacturing a master according to the present invention, and FIGS. 5B to 5H are cross-sectional views of the recording master after exposure. 6A and 6B are cross-sectional views of still another example of the recording master used in the master manufacturing method of the present invention. FIGS. 7A and 7B are cross-sectional views of the recording master disk before the second etching in the case where the second etching is performed according to the master disk manufacturing method of the present invention, and FIGS. These are sectional views of the recording master after the second etching. FIG. 8A is another example of a recording master used in the method for manufacturing a master according to the present invention, and FIGS. 8B to 8D are schematic diagrams showing a method for manufacturing the recording master shown in FIG. . FIG. 9 is a cross-sectional view of a general optical information recording medium. 10A to 10D are schematic views showing a conventional positive master manufacturing method and stamper manufacturing method, and FIG. 10E is a cross-sectional view of a negative master. FIG. 11 is a cross-sectional view showing a conventional master manufactured by heat mode recording.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Substrate 102 Recording auxiliary layer 103 Thermosensitive material layer 104 Recording master 105 State changed portion 106 State not changed 107 Metal reflecting layer 201 Recording master 202 Revolving table 203 Light source 204 Lens 205 Recording head 206 Recording light 301 Inclination angle 401 Substrate 402 Heat-sensitive material layer 403a Recording auxiliary layer 403b Recording auxiliary layer 404 Inclination angle 501 Substrate 502 Thermal material layer 503 Recording auxiliary layer 504 Recording master 505 State changed part 506 External medium 507 Unstated part 601 Substrate 602 First recording auxiliary layer 603 Heat-sensitive material layer 604 Second recording auxiliary layer 605 Recording master 605a Recording master 606 Metal reflective layer 701 Heat-sensitive material layer 702 Recording auxiliary layer 703 Lower layer 704a Recording master 704b Recording master 801 Substrate 802 Heat-sensitive material layer 03 Light transmission layer 804 Recording auxiliary layer 805 Recording master 806 Adhesive 807 Vacuum atmosphere 808 Opening 901 Optical information recording medium 902 Substrate 903 Signal layer 904 Protective layer 905 Objective lens 906 Light 1001 Substrate 1002 Photo resist 1003 Recording master 1005 Latent image 1005 Master 1006 Conductive film 1007 Metal layer 1010 Recording light 1101 Thermal material layer 1102 Atmosphere 1103 Substrate 1104 Tilt angle

Claims (25)

  The substrate is exposed to a heat sensitive material layer made of a material whose state changes due to a temperature change due to exposure, and a recording master disk made of a material different from the heat sensitive material layer. Forming a mastered portion of the optical information recording medium, including forming a processed portion, and performing a first etching under conditions with different etching rates between the state-changed portion and the state-changed portion of the heat-sensitive material layer Method.   The method for manufacturing a master of an optical information recording medium according to claim 1, wherein the recording auxiliary layer is disposed between the heat-sensitive material layer and the substrate.   The method for manufacturing a master of an optical information recording medium according to claim 2, wherein in the recording master, the thermal conductivity of the material constituting the recording auxiliary layer is different from the thermal conductivity of the material constituting the substrate.   4. The method for producing a master of an optical information recording medium according to claim 2, wherein the recording auxiliary layer increases the absorption rate of light having a wavelength used for exposure by the recording auxiliary layer.   The method for manufacturing a master of an optical information recording medium according to claim 1, wherein in the recording master, the heat-sensitive material layer is disposed between the recording auxiliary layer and the substrate.   6. The method for manufacturing a master of an optical information recording medium according to claim 5, wherein the recording auxiliary layer is removed by the first etching.   7. The method for manufacturing a master of an optical information recording medium according to claim 5, wherein in the recording master, the thermal conductivity of the material constituting the recording auxiliary layer is different from the thermal conductivity of a medium in contact with the surface of the recording master.   In the recording master, the recording auxiliary layer includes a first recording auxiliary layer and a second recording auxiliary layer, and the first recording auxiliary layer is disposed between the thermosensitive material layer and the substrate. The method for producing a master of an optical information recording medium according to claim 1, wherein the thermosensitive material layer is disposed between the first recording auxiliary layer and the second recording auxiliary layer.   The method for manufacturing a master of an optical information recording medium according to claim 8, wherein in the recording master, the thermal conductivity of a material constituting the first recording auxiliary layer is different from a thermal conductivity of a material constituting the substrate.   The optical recording medium master manufacturing method according to claim 8 or 9, wherein in the recording master, the thermal conductivity of the material constituting the second recording auxiliary layer is different from the thermal conductivity of the medium in contact with the surface of the recording master. Method.   11. The method for manufacturing a master of an optical information recording medium according to any one of claims 8 to 10, wherein, in the recording master, the absorption rate of light having a wavelength used for exposure by the recording auxiliary layer is increased.   The optical information recording medium according to any one of claims 1 to 11, wherein in the recording master, a metal reflective layer is disposed at a position closer to the substrate than any of the heat-sensitive material layer and the recording auxiliary layer. Master production method.   In the recording master, the recording auxiliary layer is disposed between the metal reflective layer and the heat-sensitive material layer, and the thermal conductivity of the material constituting the recording auxiliary layer is the thermal conductivity of the material constituting the reflective layer. 13. A method for producing a master of an optical information recording medium according to claim 12, which is smaller than the master disc.   The first etching is performed under the condition that the etching rate of the recording auxiliary layer is lower than the etching rate of the high etching rate portion of the heat-sensitive material layer where the state has changed and the portion where the state has not changed. 14. The method for producing a master for an optical information recording medium according to any one of claims 1, 2, 3, 4, 8, 9, 10, 11, 12 and 13.   After selectively removing the heat-sensitive material layer by the first etching, performing a second etching using the heat-sensitive material layer as a mask, and removing the heat-sensitive material layer after the second etching The master of the optical information recording medium according to any one of claims 1, 2, 3, 4, 8, 9, 10, 11, 12, 13 and 14, further comprising performing a third etching. Production method.   The recording master has a configuration in which the recording auxiliary layer is positioned between the heat-sensitive material layer and the substrate, and the depth of etching the recording auxiliary layer by the second etching is d1, the second etching When the average thickness of the previous heat-sensitive material layer is d2, the second etching is performed under the condition that the etching selectivity of the recording auxiliary layer to the heat-sensitive material layer is larger than d1 / d2. The method for producing a master of the optical information recording medium according to claim 15.   The second etching is performed so that an etching selectivity of the recording auxiliary layer to a layer disposed in contact with the recording auxiliary layer and located near the substrate is greater than 1. 16. A method for producing a master of an optical information recording medium according to 16.   In the recording master, a light transmission layer made of a material having a refractive index of 1.35 or more and 1.65 or less at a wavelength of light used for the exposure is more than the heat-sensitive material layer and the recording auxiliary layer. 18. The method for manufacturing a master of an optical information recording medium according to claim 1, wherein the optical transmission layer is disposed at a position far from the substrate, and the light transmission layer is removed after the exposure. In the recording master, the thermosensitive material layer includes one or both of Te and Sb, one or more elements selected from Au, Pt, Ag and Cu, and O, and the recording auxiliary layer includes ZnS. and wherein one or both of the SiO _2, the exposure is performed by using a laser beam, the optical information recording medium according to any one of claims 1 to 18 wherein the first etching is alkaline etching Master production method.   The optical recording medium manufacturing method according to claim 1, wherein the recording auxiliary layer includes a resin material.   21. The method for producing a master for an optical information recording medium according to claim 1, wherein the recording auxiliary layer includes an inorganic material and is formed by a vapor deposition method or a sputtering method.   The method for manufacturing a master of an optical information recording medium according to any one of claims 1 to 21, wherein an inclination angle of a concave portion or a convex portion formed on the master by the first etching is not less than 50 degrees and not more than 73 degrees.   A master disc manufactured by the method for manufacturing a master disc of an optical information recording medium according to any one of claims 1 to 22.   The stamper manufactured using the original disc manufactured with the original disc manufacturing method of the optical information recording medium of any one of Claims 1-22. An optical information recording medium manufactured using a master manufactured by the method for manufacturing a master of an optical information recording medium according to any one of claims 1 to 22.

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