KR101095367B1 - Method of forming pattern using crystalstructure of material - Google Patents

Abstract

The present invention relates to a pattern forming method for easily and clearly forming nanoscale patterns using a crystal structure of a material. In the pattern formation method using the crystal structure of the material according to the present invention, after placing a target material having a lattice image defining a line in a chamber, the target material is irradiated with a first electron beam to the substrate on which the electron beam resist is formed. It is exposed to the 1st electron beam which passed through. After rotating the grid image, a second electron beam is irradiated to the target material to expose the substrate on which the electron beam resist is formed to the second electron beam that has passed through the target material. The electron beam resist is developed to form an electron beam resist pattern, and an underlayer formed under the electron beam resist pattern is etched through the electron beam resist pattern to form a pattern.

Description

Method of forming pattern using crystalstructure of material

The present invention relates to nanotechnology, and more particularly, to a method of forming a pattern using a crystal structure of a material.

Recently, as the degree of integration of devices increases, a lot of researches have been made to form nanoscale patterns. In particular, studies for forming nanodot or nanowire patterns have been actively conducted. Nano dot or nano wire pattern forming process has emerged as a key process for forming such devices as the application of electric devices, magnetic devices and optical devices using nano dots or nano wires has emerged. The basic principle of operation of electrical devices, magnetic devices, and optical devices using nanodots and nanowires is that quantum mechanics indicates that when the physical size of a particle is in nanometers, the overall physical properties of the particle are greatly affected by the particle size. Mac goes along with development.

It is currently reported that an electron beam lithography process using hydrogen silsesquioxane (HSQ) as an electron beam resist can form a single line pattern having a size of 10 nm or less. However, this is limited to a single line pattern, and the minimum wiring width is limited at 20 nm in a high density pattern having a ratio of feature size and line spacing of 1: 1. In addition, it is difficult to form nanodots of the same size to have a uniform density.

Further, as shown in FIG. 1, the pattern 2 in which the nanowires 3 are arranged in rows and columns on the substrate 1, or the protrusions 7 on the substrate 5 as shown in FIG. 2. There is a further lack of research to form a pattern 6 in which the pattern 6 is arranged spaced apart at nanoscale intervals in rows and columns.

The technical problem to be solved by the present invention is to provide a method for easily and uniformly forming a nano-size pattern that is clearly defined using the crystal structure of the material.

In order to solve the above technical problem, a preferred embodiment of the pattern forming method using the crystal structure of the pattern material according to the present invention by irradiating an electron beam to the target material having a crystal structure located in the chamber, A method of forming a pattern from a grid image formed by interference of a transmission electron beam and a diffraction electron beam, the method comprising: positioning a target material having a grid image defining a line in the chamber; Irradiating the first electron beam to the target material to expose the substrate on which the electron beam resist is formed to the first electron beam passing through the target material; Rotating the grid image; Irradiating a second electron beam to the target material to expose the substrate on which the electron beam resist is formed to a second electron beam passing through the target material; Developing the electron beam resist to form an electron beam resist pattern; And etching the underlayer formed under the electron beam resist pattern through the electron beam resist pattern to form a pattern.

In the pattern forming method according to the present invention, the target material may be rotated so that the grid image is rotated so that the irradiation direction of the electron beam is in the direction of the rotation axis.

In order to solve the above technical problem, another preferred embodiment of the pattern forming method using the crystal structure of the pattern material according to the present invention by irradiating an electron beam to the target material having a crystal structure located in the chamber, A method of forming a pattern from a grid image formed by interference of a transmission electron beam and a diffraction electron beam, the method comprising: positioning a target material having a grid image defining a line in the chamber; Irradiating the first electron beam to the target material to expose the substrate on which the electron beam resist is formed to the first electron beam passing through the target material; Rotating the substrate on which the electron beam resist is formed with the irradiation direction of the electron beam as a rotation axis direction; Irradiating a second electron beam to the target material to expose the substrate on which the electron beam resist is formed to a second electron beam passing through the target material; Developing the electron beam resist to form an electron beam resist pattern; And etching the underlayer formed under the electron beam resist pattern through the electron beam resist pattern to form a pattern.

In the method of forming a pattern according to the present invention, in order to form a pattern in which a plurality of nanowires are arranged in rows and columns on the substrate, the electron beam resist may use a negative electron beam resist. . The electron beam resist may use a positive electron beam resist to form a pattern in which a plurality of protrusions are arranged to be spaced apart from each other in rows and columns on the substrate. In addition, the electron beam resist is a negative electron beam resist in which a portion irradiated with an electron beam more than a critical charge amount per unit area is not removed during development, and in order to form a nanodot pattern, the charge amount per unit area of the first electron beam and the second electron beam are not removed. Each charge amount per unit area is smaller than the threshold charge amount, and the charge amount per unit area of the first electron beam and the second electron beam is increased so that the sum of the charge amount per unit area of the first electron beam and the charge amount per unit area of the second electron beam is larger than the threshold charge amount. Can be set.

According to the present invention, a pattern is formed using a crystal structure of a material, and a lattice-shaped pattern can be easily formed by exposing an electron beam, rotating a lattice image or a substrate, and then exposing the electron beam again. In addition, when the pattern is formed in this manner, the pattern is not only clearly defined, but also a nano-sized pattern having a uniform interval or size can be formed.

The present invention relates to a method of forming a pattern using a pattern forming apparatus using a crystal structure of a material. Therefore, before describing the present invention, a pattern forming apparatus using the crystal structure of the material used in the present invention will be described.

First, the crystal lattice structure of general materials and various schematic diagrams thereof will be described in order to facilitate understanding of the pattern forming apparatus used in the present invention.

It is well known that almost all materials present on Earth are composed of atoms and molecules which are a combination of several of these atoms. Particularly, solid materials are "a periodic arrangement of atoms, ions or molecules. State ", or crystalline, and amorphous by the disordered combination of these atoms. The study of the regular arrangement of these atoms began in 1912 when Max von Laue discovered X-ray diffraction. Subsequently, in 1913, Bragg Riche analyzed the simple crystal structure of diamonds and salts by X-ray, followed by Ewald in 1920. To date, the crystal structure (cyclic arrangement of atoms) of over 100,000 organic and inorganic chemicals on Earth has been identified.

If you move a point parallel to a certain distance a in a certain direction, it becomes the second point, and if you move it again the same distance in the same direction, a third point is created. Repeatedly moving one point in this manner creates a point sequence as shown in FIG. 3A. Here, the point sequence generated by the overlapping of the movement of moving a point by a specific distance in a constant direction is called a grid line. In this case, an operation of moving a certain distance in a predetermined direction is called translation and can be expressed as a using a vector. Here, the specific distance, that is, the absolute value a of the vector, is called a period or unit period. In this sequence, each point is the same and if one point is taken as the origin, the other points can be represented by the position vector from the origin.

That is, r = ma

Where m is an integer from -∞ to + ∞.

Translation of this point sequence in the other direction results in a point network as shown in FIG. 3B, which is called a lattice plane. When the lattice plane is moved in parallel by a translation c in a third direction which is not parallel to the rear face, a three-dimensional point network is formed, which is called a spatial lattice. In a grid of grids, each grid point is defined by a position vector r from either origin

r = ma + nb + pc

. Where m, n, p are integers between -∞ and + ∞. That is, the space grid is infinitely expanded on the infinite space as shown in FIG. 3C.

The fact that a crystal is macroscopically homogeneous is that the nature of any part of the crystal is the same as the part that is separated by an arbitrary distance from this part. 4 shows an arbitrary hypothetical crystal structure, and as shown here, any point P in the crystal is defined as a position vector from the origin and is called L, and the unit translation vector of the lattice forming this crystal is shown. a, b, c

L = Xa + Yb + Zc

= (m + x) a + (n + y) b + (p + z) c = (ma + nb + pc) + (xa + yb + zc)

= r _l + r

Where X, Y and Z are real numbers and x, y and z are prime numbers from 0 to 1, i.e. any point in space is represented by r _l representing the crystal lattice and r representing the position vector in the lattice. . Here, the unit grid defined by the three translation vectors may be referred to as a unit cell.

Here, if an arbitrary point in the crystal is defined as the origin (0,0,0), the same points as all origins in the lattice woven from this point, that is, the lattice points have the same properties as each other. In other words, no matter which point in the crystal is the origin, the lattice points that can be considered to be caused by the translation of this point are the same, where the same is the geometrical shape of the surrounding environment or the atoms located near this point. It means that all the physical properties such as chemical properties such as kinds of electrons and electron density and potential difference are the same. That is, the lattice points are identical in all geometric, chemical, and physical properties.

Due to the interrelationship of the three vectors, i.e., a, b, and c, which determine the unit cell, all the crystallines belong to one of the seven crystal axes described below. Table 1 below shows the relationship between lattice constants defining three axes.

In addition, all the crystallites have one of fourteen bravais gratings as shown in FIG. 5. This is a simple cell (P) with one lattice point in the unit cell, a low grating (A, B or C) with a unit cell with one lattice point in the center of one face, and a lattice point in the center of each face It is classified according to the number of lattice points in the unit cell, such as the face-center lattice F having and the lattice lattice I having one lattice point in the center of the unit cell.

The crystal structures of more than 100,000 organic and inorganic chemicals known to date are divided into one of the seven crystal axes listed above and 14 Bravais spatial lattice, and the actual crystal structure consists of the 14 Bravais spatial lattices defined above. It is made up of one or more arrangements of the same or different atoms at the lattice points they represent.

Next, some examples of such crystal structures are given, and the shape by the arrangement of atoms that appears when the crystal structure is projected in a particular crystal direction is described.

For example, Al corresponds to a cubic crystal axis system (a = b = c) and is a facet cell of a Bravais lattice, and thus has four lattice points in one unit cell. The crystal structure of Al is achieved by arranging one Al atom at this lattice point, where the lattice constant a = b = c = 0.404 nm. Therefore, the structure of the unit cell of Al is as shown in Figure 6a. 6B, 6C, and 6D show the pattern represented by the arrangement of atoms through the Al in [100], [110], and [111] directions.

Another example is the case of Si having a diamond crystal structure. Si has a cubic crystal axis system and, like Al, has a Bravais space lattice corresponding to a face center lattice (face centered cubic). Therefore, four grid points are included in one unit cell. Unlike a simple face-centered cubic system, two Si atoms are arranged at one grid point (lattice constant a = b = c = 0.543 nm). Therefore, eight atoms are arranged in one unit cell. 7A shows this unit cell of Si. 7B, 7C, and 7D show two-dimensional patterns represented by Si atoms when the Si crystal lattice is transmitted through the [100], [110], and [111] directions in the same manner as described above. give. FIG. 7E is a shape when FIG. 7B is rotated 56 degrees clockwise and 15 degrees azimuth. It can be seen that the image shown in FIG. 7C is shaped like several lines. This can be said to be an example that can be applied sufficiently in the form of nanowires depending on the Si single crystal processing.

Another example is the crystal structure of GaAs. GaAs, like Al and Si, has a cubic system of crystal axes and, like Al and Si, also has a Bravais spatial lattice, which corresponds to a face-centered lattice. However, unlike Al and Si having a simple cubic lattice, it is a crystal structure in which one Ga and one As atom are arranged at one lattice point (lattice constant a = b = c = 0.565 nm). The unit cell of the GaAs crystal structure is illustrated in FIG. 8A, and the two-dimensional pattern shown when the GaAs crystal structure is transmitted through the [100], [110], and [111] directions in the same manner is illustrated in FIGS. 8C and 8D, respectively. FIG. 8E is a shape when the FIG. 8C is rotated 56 degrees clockwise and 15 degrees azimuth similarly to FIG. 7E. Like Si, GaAs single crystal is an example that can be sufficiently applied in the form of nanowires.

Al, Si, and GaAs described above are only a few examples of the arrangement of atoms in the crystal structure, and more than 100,000 known crystal structures are transmitted in two dimensions along a specific crystal direction to show the pattern represented by the atoms. This is only part of the idea that a wide variety of patterns can occur. Of course, these patterns vary depending on the crystal direction and the crystal structure.

The arrangement of atoms in the crystalline described above can be observed using phase contrast imaging of a high resolution transmission electron microscope. With the development of electron microscopes up to now, it is possible to observe the arrangement of atoms in the region of 0.14 nm to 0.20 nm at an acceleration voltage of 200 to 300 kV. Phase contrast imaging is a method of obtaining an image using a path difference between one or more diffraction beams and a transmission beam generated by a crystalline sample. Other methods of obtaining an image using an electron microscope (e.g., diffraction contrast or absorption Superior resolution compared to contrast).

FIG. 9 is a schematic diagram of recombination of electron beams and transmission beams diffracted by a sample in an image plane to generate an interference fringe due to their phase difference.

An object material 220 having a crystal structure processed to a thickness of several tens of nanometers so as to transmit the electron beam 210 is placed in a chamber. The electron beam 210 is divided into a transmission electron beam and a diffraction electron beam by the target material 220 having a crystal structure processed to several tens of nanometers in thickness. The transmission electron beam and the diffraction electron beam divided while passing through the target material 220 having a crystal structure pass through the objective lens 230 and the objective lens aperture 240, and then interfere with each other to form a material having a crystal structure in space. Form a grid image. In the present invention, the image plane refers to a plane in space in which a grid image of a material having a crystal structure is formed by interfering a transmission electron beam and a diffraction electron beam divided while passing through the target material 220. An image formed on the image plane 250 is enlarged or reduced with an intermediate lens or used as it is to form a pattern.

The spacing of the interference fringes formed here is consequently proportional to the diffraction grating, i.e., the atomic plane spacing, present in the sample. By using this interference fringe, the arrangement of atoms in the atomic plane can be observed. In the actual use of high resolution electron microscopes, the primary interference fringes formed by the objective lens are gradually magnified (final magnification of several hundred thousand times) through several lenses in the rear of the objective lens, so that we can directly observe them. It becomes possible. In general, the magnification of an objective lens used is tens to hundreds of times. For example, an array of atoms having a 0.3 nm spacing has an interval of 30 nm assuming a magnification of the objective lens 100 times in the primary image plane. Appear as interference fringes. When the generated interference fringe is enlarged or reduced by using several rear lenses, an image of an atomic beam or an atomic beam of several nm to several tens of nm is obtained.

The pattern forming apparatus used in the present invention forms a pattern using the crystal structure of the material through the above-described method. That is, by placing the target material having a crystal structure in the chamber of the transmission electron microscope, irradiating the electron beam, and using the interference of the transmission electron beam and the diffraction electron beam transmitted through the target material to phase the lattice image of the target material on the surface of the irradiated material By forming using a contrast imaging method, a grid image pattern of a material can be formed. The pattern formed using the crystal structure of the material is determined according to the form of the crystal structure of the material used. Therefore, the arrangement of each atom and the distance between each atom in the crystal structure of the material are realized as it is in proportion to the finally formed pattern.

In this case, the lattice image of the material formed on the image plane may be enlarged or reduced according to a desired size, and then the electron beam resist formed on the substrate may be exposed. In this case, the image formed on the electron beam resist may be a part of the grid image of the material located in the chamber of the electron microscope. The electron beam resist may be a hydrogen silsesquioxane (HSQ).

The acceleration voltage of the electron beam of the pattern forming apparatus used in the present invention is the atomic plane spacing of the material, the alignment of the electron beam, the degree of vacuum in the transmission electron microscope column, the degree of correction of the astigmatism of the electron lens that deflects the electron beam. And the brightness of the electron gun. In general, acceleration voltages of 100 keV to 1 MeV are used. Acceleration voltages of 100 keV for materials with atomic plane spacing of 3 Å or more are 200 keV for materials with atomic plane spacing of 2 Å. A degree of acceleration voltage is required.

10A is a block diagram illustrating a pattern forming apparatus using a transmission electron microscope according to an embodiment of the present invention, and FIG. 10B is a schematic diagram of FIG. 10A.

10A and 10B, the pattern forming apparatus 300 used in the present invention is suitable for patterning the transmission electron microscope 310 and the crystal structure of the material formed by the transmission electron microscope 310. A substrate moving device 330 having a substrate cassette 331 on which a plurality of substrates 332 installed at a position are mounted.

The transmission electron microscope 310 includes an electron gun 311 for irradiating the accelerated electron beam by accelerating the electron beam with a high energy sufficient to pass a target material, a focusing apparatus for focusing the electron beam irradiated from the electron gun 311, and an electron beam. An additional focusing device for focusing light at a fixed spot, a mounting means 315 for mounting a target material through which an electron beam passes, and an objective lens for forming a grating image by a transmission electron beam and a diffraction electron beam divided while passing through the target material 316 and a desired size by being interposed between the plurality of lens groups 321, 322, 323 and the lens groups 321, 322, 323 provided to enlarge or reduce the grid image formed by the objective lens 316. It consists of a substrate transfer device 330 having a substrate 332 that can form a grid image of the.

A condenser lens 312 may be used as the focusing device, and an objective lens 314 may be used as the additional focusing device. In the plurality of lens groups 321, 322, and 323, a pattern lens 321, an intermediate lens 322, and a projector lens 323 may be alternately or sequentially used.

In addition, the substrate moving device 330 may be sequentially interposed between the lens groups 321, 322, and 323 on the substrate cassette 331 on which the plurality of substrates 332 are mounted. On the interposed substrate 332, an underlayer and an electron beam resist are sequentially stacked.

10A and 10B show a configuration in which a relatively small pattern is formed on a substrate. The image obtained by the objective lens 315 (when an image magnified by 20 times by the objective lens is considered, for example) is shown. The concept of adjusting to a desired magnification using a predetermined pattern lens 321 and then creating an image magnified 100,000 times using at least one or more intermediate lenses 322 is shown. For example, in the case of 10 to 100 times the magnification of the desired image, the image formed on the image plane of the objective lens 315 should be reduced by 1/2 times using the pattern lens 321. In the case of 100 times, the image formed on the image plane of the objective lens 315 should be enlarged 5 times using the pattern lens 321.

That is, after adjusting the focus of the image and the like magnified 100,000 times, the pattern may be formed by interposing the substrate 332 using the substrate transfer device 330 in the image plane of the pattern lens 321.

Hereinafter, exemplary embodiments of a pattern forming method using a crystal structure of a material according to the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various forms, and only the present embodiments are intended to complete the disclosure of the present invention and to those skilled in the art to fully understand the scope of the invention. It is provided to inform you.

11 is a flowchart illustrating a process of performing a preferred embodiment of the method for forming a pattern using a lattice structure of a material according to the present invention.

Referring to FIG. 11, first, a target material is loaded into a mounting means 315 of a pattern forming apparatus, for example, the pattern forming apparatus 300 of FIG. 10 using the crystal structure of the material described above (S410). The grating image formed by the interference of the transmission electron beam and the diffraction electron beam of the target material defines a line. To have a lattice image defining a line, the subject material can process silicon as shown in FIG. 7E, or GaAs as shown in FIG. 8E.

Next, by irradiating a first electron beam to a target material having a lattice image defining the line, a first exposure step of exposing the substrate on which the electron beam resist is formed to the first electron beam passing through the target material. (S420). After rotating the grid image (S430) or rotating the substrate (S440), a second electron beam is irradiated to the target material to expose the substrate on which the electron beam resist is formed to the second electron beam passing through the target material. A second exposure step is performed (S450). In step S430, the grid image is rotated so that the object is rotated with the irradiation direction of the electron beam as the rotation axis direction so that the grid image is rotated. In operation S440, the substrate is rotated by using the electron beam as the rotation axis.

Since the electron beam passing through the target material has information defining a line, the electron beam is exposed (S420) before rotating the grid image (S430) or rotating the substrate (S440), and then exposing the electron beam again (S450). In this case, the electron beam resist has the same effect as that exposed to an electron beam having a grid image in which a plurality of lines are arranged in rows and columns. This is illustrated in FIGS. 12 and 13.

12 and 13 illustrate simulation results of a grid image obtained by combining a grid image before and after the grid image rotation and a grid image before and after the grid image rotation. FIG. 12 illustrates a case where the grid image is rotated 90 degrees. The case of 60 degree rotation is shown.

As shown in Figs. 12 and 13, when the electron beam is exposed before rotating the grid image, and the electron beam is exposed after the grid image is rotated, each grid image has a pattern in the form of a line. It can form a pattern of a cross-arranged form.

The grid image may be selected from a range of 0 to 180 degrees according to the pattern to be formed. In addition, by using the above-described pattern forming apparatus, it is possible to form a pattern having a desired size if it is enlarged or reduced. For the uniformity of the formed pattern, the first electron beam and the second electron beam may use the same one. In particular, it is preferable to use the same charge amount per unit area of the first electron beam as the charge amount per unit area of the second electron beam.

11 again, after the second exposure S450, the electron beam resist is developed to form an electron beam resist pattern (S460), and then an underlayer formed under the electron beam resist pattern using the electron beam resist pattern. layer) to form a pattern (S470).

Example  1: negative electron beam Resist Example  One

14 is a diagram illustrating a process of forming a pattern in which a plurality of nanowires are arranged in rows and columns by using a negative electron beam resist.

Referring to FIG. 14, first, as shown in FIG. 14A, a substrate 510 in which a base layer 520 and a negative electron beam resist 530 are sequentially stacked is prepared. The base layer 520 corresponds to a layer that is actually patterned, and when the substrate 510 is patterned, a separate underlayer is not required.

The substrate 510 on which the base layer 520 and the negative electron beam resist 530 are sequentially stacked is loaded into the pattern forming apparatus 300 (FIG. 10A). As illustrated in FIG. 11, after the first exposure S420, the object is rotated to rotate the grid image (S430), and then the second exposure S450. When the electron beam is exposed before and after the lattice image rotation as described above, the electron beam having the form as shown in the bottom of FIGS. 12 and 13 is irradiated to the negative electron beam resist 530 formed on the substrate 530. 12 and 13 are portions where the electron beam is irradiated. After the first exposure S420 and the second exposure S450 are performed, the electron beam resist 530 is developed. As shown in FIG. 14B, the plurality of nanowires cross each other in rows and columns. The electron beam resist pattern 535 is formed. Since the negative electron beam resist was used, the portion to which the electron beam was irradiated during development remained, and the portion to which the electron beam was not irradiated was removed to form an electron beam resist pattern 535 as shown in Fig. 14B.

When the underlying layer 520 is etched using the electron beam resist pattern 535, as shown in FIG. 14 (c), the pattern 525 may be formed in which nanowires are arranged in rows and columns. .

Scanning electron microscopy (SEM) photographs of the pattern 525 formed by the method of FIG. 14 are shown in FIGS. 15 and 16. 15 is a low magnification SEM photograph, and FIG. 16 is a high magnification SEM photograph. At this time, the electron beam resist was HSQ, which is a negative electron beam resist, and the amount of charge per unit area of the first electron beam and the second electron beam was equal to 500 μC / cm ² .

As shown in FIGS. 15 and 16, when the pattern is formed by the method of the present embodiment, it can be seen that the pattern in which the nanowires are arranged in rows and columns can be easily formed. And not only the pattern is clearly defined, it can be seen that each nanowire has a uniform size, each nanowire has a uniform spacing.

Example  2: negative electron beam Resist Example  2

17 illustrates a process of forming a nano dot pattern using a negative electron beam resist.

Referring to FIG. 17, first, as shown in FIG. 17A, a substrate 610 in which a base layer 620 and a negative electron beam resist 630 are sequentially stacked is prepared. The underlayer 620 corresponds to a layer that is actually patterned, and when the substrate 610 is patterned, a separate underlayer is not necessary. The negative electron beam resist is an electron beam resist having the property that the portion irradiated with the electron beam remains upon development and the portion not irradiated with the electron beam is removed upon development. However, even if the electron beam is irradiated, when the electron beam with a small amount of charge per unit area is irradiated, it is removed during development. Therefore, only the portion to which the electron beam irradiated with the amount of charge per unit area or more is left at the time of development.

The substrate 610 on which the base layer 620 and the negative electron beam resist 630 are sequentially stacked is loaded into the pattern forming apparatus 300 (FIG. 10A). As illustrated in FIG. 11, after the first exposure S420, the object is rotated to rotate the grid image (S430), and then the second exposure S450.

In this case, each of the first electron beam irradiated for the first exposure S420 and the second electron beam irradiated for the second exposure S450 is set such that the charge amount per unit area is smaller than the critical charge amount of the negative electron beam resist 630. The first electron beam and the second electron beam are set such that the sum of the charge amount per unit area of the first electron beam and the charge amount per unit area of the second electron beam is larger than the threshold charge amount. As such, when the amount of charge per unit area of the first electron beam and the second electron beam is set, only the portion where the electron beam is irradiated in the first exposure S420 and the second exposure S450 overlaps with the amount of charge per unit area of the negative electron beam resist 630. It becomes more than the critical charge amount of and remains at the time of image development. All other portions are removed at the time of development because only the charge amount less than the threshold charge amount of the negative electron beam resist 630 is irradiated or the electron beam is not irradiated.

That is, when the first exposure S420 and the second exposure S450 are performed, an electron beam having a shape as shown in the lower images of FIGS. 12 and 13 is irradiated, and the first exposure S420 and the second exposure S450 are performed. The portion where the electron beam is irradiated is the portion where each line overlaps. As a result, after the first exposure S420 and the second exposure S450 are performed, when the negative electron beam resist 630 is developed, only the negative electron beam resist 630 corresponding to the portion where each line overlaps remains. All remaining portions are removed to form an electron beam resist 635 pattern as shown in Fig. 17B.

If the underlying layer 620 is etched using the electron beam resist pattern 635, the nanodot pattern 625 may be formed as shown in FIG. 17C.

If the nano dot pattern 625 is formed through the above method, the nano dot pattern may be formed at a desired position, and the nano dot pattern 625 having a uniform size of the nano dot and a space between the nano dots may be obtained. It is easy to adjust the size of the nano-dots and the interval between the nano-dots.

Example  3: positive electron beam Resist Example

18 is a diagram illustrating a process of forming a pattern in which a plurality of protrusions are arranged spaced apart in rows and columns using a positive electron beam resist.

Referring to FIG. 18, first, as shown in FIG. 18A, a substrate 710 in which a base layer 720 and a positive electron beam resist 730 are sequentially stacked is prepared. The underlayer 720 corresponds to a layer that is actually patterned, and when the substrate 710 is patterned, a separate underlayer is not required.

The substrate 710 in which the base layer 720 and the negative electron beam resist 730 are sequentially stacked is loaded into the pattern forming apparatus 300 (FIG. 10A). As illustrated in FIG. 11, after the first exposure S420, the object is rotated to rotate the grid image (S430), and then the second exposure S450. When the electron beam is exposed before and after the lattice image rotation as described above, the electron beam having the form as shown in the bottom of FIGS. 12 and 13 is irradiated to the positive electron beam resist 730 formed on the substrate 730. 12 and 13 are portions where the electron beam is irradiated. The positive electron beam resist has a property opposite to that of the negative electron beam resist. When developing after the electron beam irradiation, the portion irradiated with the electron beam is removed and the portion not irradiated with the electron beam remains. Therefore, it is possible to form a pattern of the opposite shape to FIG.

That is, after the first exposure S420 and the second exposure S450 are performed, and the electron beam resist 730 is developed, the plurality of protrusions are arranged to be spaced apart from each other in rows and columns as shown in FIG. The electron beam resist pattern 735 is formed. The spacing between each protrusion may be nano sized.

When the underlying layer 720 is etched using the electron beam resist pattern 735, the protrusions may be formed to form a pattern 725 in which the protrusions are spaced apart from each other in rows and columns as shown in FIG. 18 (c). do.

When the pattern 725 is formed in this way, the protrusions may be easily formed in a pattern in which the protrusions are spaced so as to have nano-sized intervals in rows and columns. And the spacing of each protrusion can be made uniform, and the size and spacing of the protrusions can be easily adjusted.

Although the preferred embodiments of the present invention have been shown and described above, the present invention is not limited to the specific preferred embodiments described above, and the present invention belongs to the present invention without departing from the gist of the present invention as claimed in the claims. Various modifications can be made by those skilled in the art, and such changes are within the scope of the claims.

1 and 2 illustrate examples of nanoscale patterns.

3A is a schematic diagram of one-dimensional translation of lattice points.

3B is a schematic diagram of two-dimensional translation of lattice points.

3C is a schematic diagram of three-dimensional translation of grid points.

4 is a schematic diagram showing an arrangement of atoms around a lattice point.

5 is an explanatory diagram showing a crystal axis system and a Bravais lattice of a substance.

6A is a diagram illustrating a unit cell of an Al crystal structure.

FIG. 6B is a view showing the crystal structure of Al penetrating in the [100] direction. FIG.

FIG. 6C is a view showing the crystal structure of Al penetrating in the [110] direction. FIG.

FIG. 6D is a view showing the crystal structure of Al penetrating in the [111] direction. FIG.

It is a figure which shows the structure of the unit cell of the crystal structure of Si.

7B is a diagram showing the crystal structure of Si penetrating in the [100] direction.

7C is a diagram showing the crystal structure of Si penetrating in the [110] direction.

FIG. 7D is a view showing the Si crystal structure penetrated in the [111] direction. FIG.

FIG. 7E is a view of rotating FIG. 7C clockwise 56 degrees and azimuth 15 degrees.

8A is a diagram illustrating a unit cell of a GaAs crystal structure.

8B is a diagram showing the GaAs crystal structure penetrated in the [100] direction.

8C is a diagram showing the GaAs crystal structure penetrated in the [110] direction.

8D is a diagram showing the GaAs crystal structure penetrated in the [111] direction.

FIG. 8E is a view of rotating FIG. 8C clockwise 56 degrees and azimuth 15 degrees.

9 is a schematic diagram of a transmission electron microscope used in the pattern forming method of the pattern forming apparatus used in the present invention.

10A and 10B are diagrams showing a schematic configuration of a pattern forming apparatus used in the present invention.

11 is a flowchart illustrating a process of performing a preferred embodiment of the method for forming a pattern using a lattice structure of a material according to the present invention.

12 and 13 illustrate results of a simulation of a grid image obtained by adding a grid image before and after a rotation and a grid image before and after a rotation in the pattern forming method according to the present invention. 13 shows the case of rotating 60 degrees.

14 is a diagram illustrating a process of forming a pattern in which a plurality of nanowires are arranged in rows and columns by using a negative electron beam resist.

15 and 16 are scanning electron microscopy (SEM) images of the pattern formed by the method of FIG. 14.

17 illustrates a process of forming a nano dot pattern using a negative electron beam resist.

18 is a diagram illustrating a process of forming a pattern in which a plurality of protrusions are arranged spaced apart in rows and columns using a positive electron beam resist.

Claims (7)

By irradiating an electron beam to a target material having a crystal structure located in the chamber, to form a pattern from the grid image formed by the interference of the transmission electron beam and the diffraction electron beam passing through the target material, Positioning an object having a grid image defining a line in the chamber; Irradiating the first electron beam to the target material to expose the substrate on which the electron beam resist is formed to the first electron beam passing through the target material; Rotating the grid image; Irradiating a second electron beam to the target material to expose the substrate on which the electron beam resist is formed to a second electron beam passing through the target material; Developing the electron beam resist to form an electron beam resist pattern; And And etching a base layer formed under the electron beam resist pattern through the electron beam resist pattern to form a pattern. The method of claim 1, Rotating the grid image And rotating the target material in such a way that the irradiation direction of the electron beam is rotated so that the grid image is rotated. By irradiating an electron beam to a target material having a crystal structure located in the chamber, to form a pattern from the grid image formed by the interference of the transmission electron beam and the diffraction electron beam passing through the target material, Positioning an object having a grid image defining a line in the chamber; Irradiating the first electron beam to the target material to expose the substrate on which the electron beam resist is formed to the first electron beam passing through the target material; Rotating the substrate on which the electron beam resist is formed with the irradiation direction of the electron beam as a rotation axis direction; Irradiating a second electron beam to the target material to expose the substrate on which the electron beam resist is formed to a second electron beam passing through the target material; Developing the electron beam resist to form an electron beam resist pattern; And And etching a base layer formed under the electron beam resist pattern through the electron beam resist pattern to form a pattern. The method according to any one of claims 1 to 3, And a charge amount per unit area of the first electron beam and a charge amount per unit area of the second electron beam. The method according to any one of claims 1 to 3, The electron beam resist is a pattern forming method, characterized in that for forming a pattern in which a plurality of nanowires are arranged in rows and columns on the substrate by using a negative electron beam resist. The method according to any one of claims 1 to 3, And the electron beam resist using a positive electron beam resist to form a pattern in which a plurality of protrusions are arranged spaced apart from each other in rows and columns on the substrate. The method according to any one of claims 1 to 3, The electron beam resist is a negative electron beam resist in which a portion to which an electron beam is irradiated more than a critical charge amount per unit area is not removed during development, In order to form a nanodot pattern, the charge amount per unit area of the first electron beam and the charge amount per unit area of the second electron beam are smaller than the threshold charge amount, respectively, and the charge amount per unit area of the first electron beam and per unit area of the second electron beam. And setting the amount of charge per unit area of the first electron beam and the second electron beam such that the sum of the charge amounts is greater than the threshold charge amount.

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