JP2012501473A - Method for reticle fabrication using optical proximity correction, design and character projection lithography - Google Patents

Abstract

  A method and system for manufacturing a surface having a plurality of slightly different patterns is disclosed. The method comprises using a stencil mask having a set of characters to form a pattern on the surface and reducing the number of shots or total drawing time by using character modification techniques. Application of such methods of fracturing, mask data preparation, or proximity effect correction is also disclosed. A method for optical proximity correction of a pattern design on a substrate is also disclosed, comprising inputting a desired pattern for the substrate, some of which are complex characters and form a pattern on a surface Can be used for A method for creating a glyph is also disclosed.

Description

Cross-reference of related applications This application claims the following as priority.
1) entitled “Method and System for Manufacturing a Reticle Using Character Projection Particle Beam Lithography” filed on September 1, 2008. US patent application Ser. No. 12 / 202,364
2) “Method For Optical Proximity Correction Of A Reticle To Be Manufactured Using Character Projection Lithography” filed on September 1, 2008. US patent application Ser. No. 12 / 202,365
3) “Method And System For Design Of A Reticle To Be Manufactured Using Character Projection Lithography” filed on September 1, 2008. US patent application Ser. No. 12 / 202,366
4) US patent application entitled “Method and System for Manufacturing a Reticle Using Character Projection Lithography” filed on November 12, 2008. Number 12 / 269,777
And all of them are hereby incorporated by reference for all purposes.

BACKGROUND OF THE DISCLOSURE The present disclosure relates to lithography, and more particularly to the design and manufacture of surfaces that can be reticles, wafers, or any other surface using character or cell projection lithography.

  In the production or manufacture of a semiconductor device such as an integrated circuit, optical lithography can be used to manufacture the semiconductor device. Optical lithography is a printing process that creates an integrated circuit by transferring a pattern to a substrate, such as a semiconductor or silicon wafer, using a lithographic mask or reticle. Other substrates include flat panel displays and photomasks. In addition, extreme ultraviolet (EUV) lithography or X-ray lithography is considered a type of optical lithography. The reticle or reticles may include circuit patterns corresponding to individual layers of the integrated circuit, which patterns are bonded onto specific areas on a substrate coated with a layer of radiation sensitive material known as photoresist or resist. Imaged. Once the patterned layer is transferred, it undergoes various other processes such as etching, ion implantation (doping), metallization, oxidation, and polishing. These processes are employed to finish individual layers on the substrate. If several layers are required, the entire process or a variation thereof is repeated for each new layer. Ultimately, a combination of devices or integrated circuits are present on the substrate. These integrated circuits can be separated from each other by dicing or sawing and mounted in individual packages. In the more general case, the pattern on the substrate can be used to define a workpiece such as a display pixel or a magnetic recording head.

  In the production or manufacture of a semiconductor device such as an integrated circuit, maskless direct writing can also be used to manufacture the semiconductor device. Maskless direct writing is a printing process in which a pattern is transferred to a substrate such as a semiconductor or silicon wafer to create an integrated circuit. Other substrates may also include a flat panel display, an imprint mask for nanoimprint, or a photomask. The desired pattern of the layer is drawn directly on the surface, in this case also on the substrate. Once the patterned layer is transferred, it undergoes various other processes such as etching, ion implantation (doping), metallization, oxidation, and polishing. These processes are employed to finish individual layers on the substrate. If several layers are required, the entire process or a variation thereof is repeated for each new layer. Some layers can be written using optical lithography, while others are written using maskless direct writing to produce the same substrate. Ultimately, a combination of devices or an integrated circuit is present on the substrate. These integrated circuits can be separated from each other by dicing or sawing and mounted in individual packages. In the more general case, the pattern on the substrate can be used to define a workpiece such as a display pixel or a magnetic recording head.

  As shown, the lithographic mask or reticle includes a geometric pattern corresponding to the circuit elements to be integrated on the substrate. The pattern used to manufacture the reticle can be generated utilizing CAD (Computer Aided Design) software or programs. In pattern design, the CAD program can follow a set of predetermined design rules to create a reticle. These rules are set by processing, design, and end use restrictions. An example of an end use limitation is to define transistor placement in such a way that it cannot operate satisfactorily at the required supply voltage. In particular, the design rules may determine the tolerance of space between circuit devices or interconnection lines. For example, design rules are used to ensure that circuit devices and wiring do not interact with each other in an undesirable manner. For example, design rules are used to keep wires from getting close to each other in a manner that can cause a short circuit. The design rule limitations reflect, among other things, the smallest dimensions that can be reliably manufactured. When referring to these minimum dimensions, the concept of critical dimensions is usually introduced. For example, these are defined as the minimum wiring width or the minimum space between two wirings, and their dimensions require elaborate control.

  One goal of integrated circuit fabrication by optical lithography is to recreate the original circuit design on the substrate through the use of a reticle. Integrated circuit manufacturers are constantly trying to use semiconductor wafer resources as efficiently as possible. Engineers continue to reduce the size of the circuit so that the integrated circuit contains more circuit elements and can use less power. Since the critical dimension size of an integrated circuit is reduced and its circuit density is increased, the corresponding critical dimension of the mask pattern reaches the resolution limit of an optical exposure tool used in optical lithography. As the critical dimensions of the circuit layout become smaller and reach the resolution limit of the exposure tool, accurate transfer between the mask pattern and the actual circuit pattern developed on the resist layer becomes difficult. A process known as optical proximity correction (OPC) has been developed to facilitate the use of optical lithography to transfer patterns having features smaller than the wavelength of light used in the optical lithography process. . OPC changes the original pattern of the mask to compensate for distortions caused by effects such as light diffraction or optical interaction between adjacent features. OPC includes all super-resolution techniques performed using a reticle.

  OPC adds a sub-resolution lithographic feature to the mask pattern to determine the difference between the original mask pattern or design and the final circuit pattern transferred onto the substrate. To reduce. The sublithographic features interact with the original mask pattern and with each other to compensate for proximity effects and improve the final transferred circuit pattern. One feature used to improve pattern transfer is the sub-resolution assist feature (SRAF). Another feature added to improve pattern transfer is referred to as "serif". Serifs are small features placed at the corners of the pattern to sharpen the corners in the final transferred image. As the limits of optical lithography extend to subwavelength regimes, OPC features must be made increasingly complex to compensate for even finer interactions and effects. However, as an imaging system gets closer to its limits, the ability to produce reticles with sufficiently fine OPC features becomes important. Although adding serifs or other OPC features to the mask pattern is advantageous, the overall number of features in the mask pattern is also substantially increased. For example, adding a serif to each of the square corners adds eight more rectangles to the mask or reticle pattern. Adding OPC features is a very persevering task, requires costly computation time, and results in a more expensive reticle. Not only is the OPC pattern complicated, but the optical proximity effect is in a long range compared to the minimum line and space dimensions, so the correct OPC pattern at a given location will have no other shape nearby. It depends very much on what it is. Thus, for example, the line ends have different sizes depending on what is adjacent to it on the reticle. This is even though the purpose is to produce exactly the same shape on the wafer. These slight but significant changes are important and prevent others from forming a reticle pattern. It is conventional to discuss the OPC decoration pattern to be drawn on the reticle for key features that reflect the previous design of the OPC decoration, as well as OPC feature points that may include serifs, jogs, and SRAFs. . To quantify what is meant by a small change, a typical small change in OPC change from neighborhood to neighborhood can be from 5% to 80% of the main features. For clarity, it should be noted that the change in OPC design is what is referenced. In order to quantify what is meant by slight changes, typical slight changes in neighborhood-to-neighbor OPC decorations can be between 5% and 80% of key features. It should be noted that for clarity, the change in OPC design is what is referenced. Manufacturing variations such as line end roughness and corner rounding are also present in the actual surface pattern. If these OPC changes produce substantially the same pattern on the wafer, it means that the goal is to have the same shape on the wafer within the specified error range. That is, its shape depends on the details of the function, for example designed to make a transistor or wiring function. Nevertheless, typical specifications are 2% to 50% of the main feature range. Although there are many manufacturing factors that cause change, the overall erroneous OPC element is often within the listed range.

  There are many techniques used to form a pattern on a reticle, including the use of light or particle beam lithography. The most commonly used system is the variable shaped beam (VSB) type, in which a precision electron beam is shaped and directed to the reticle's resist-coated surface. These shapes are simple shapes, usually limited to rectangles with specific minimum and maximum sizes, and triangles with specific minimum and maximum sizes, 45 °, 45 °, 90 ° interior angles Is done. At predetermined positions, electron doses are shot into the resist in these simple shapes. The total drawing time for this type of system increases with the number of shots. The second type of system is a character projection system. In this case, the system has a stencil, which can be a straight line, a straight line of any angle, a circle, a ring, a part of a circle, a part of a ring, or any curvilinear shape. Have a variety of shapes, which can be a connected set of complex shapes, or a separate set of connected sets of complex shapes. An electron beam can be irradiated through the stencil to efficiently generate a more complex pattern (ie, character) on the reticle. Theoretically, such a system can be faster than a VSB system because it can illuminate a more complex shape with each time-consuming shot. That is, the “E” shot by the VSB system requires four shots, but the character projection system can be completed by one shot. Note that the shaped beam system can be considered special (simple) for character projection, in which case the character is just a simple character, usually a rectangle or a 45-45-90 triangle. . It is also possible to partially expose the character. This can be done, for example, by blocking a portion of the particle beam. For example, the “E” above can be partially exposed as F or I, but in this case, different portions of the beam are eliminated by the aperture. For very complex reticles, the pattern must be broken down into basic shapes that are almost a billion and sometimes even a trillion. For example, a VSB system has a simple rectangular shape, and a character projection system has a limited number of characters. The more all examples of basic shapes (characters) in the pattern, the longer the drawing time and the more expensive. However, such projection systems are today impractical when rendering OPC-decorated surfaces where there are numerous fine deformations even between smaller patterns. The number of characters that can be used is limited while the selection of characters by the projection device requires a minimum time, and today only about 10-1000 characters are possible. In the face of a slightly different excess of OPC patterns required to be placed on the reticle, no system or method was available that could accomplish this task.

  Thus, it would be advantageous to reduce the time and expense required to prepare and manufacture the reticle used for the substrate. More generally, it would be advantageous to reduce the time and expense required to prepare and manufacture any surface. It is also desirable to have a stencil mask that includes several complex characters that are required to generate or generate a surface with various patterns that are required to be transferred to the surface. For example, a surface can have thousands of patterns that differ only slightly from each other. In order to prepare a surface, it is desirable to have a stencil mask that can generate many of these patterns with slight differences. As discussed more fully herein, this can be achieved using a stencil mask that includes a collection of characters that can be combined, modified, or adjusted to produce a pattern with many subtle variations. It is. That is, there is a need for a method and system for manufacturing a surface that overcomes the above problems associated with preparing the surface.

SUMMARY OF THE DISCLOSURE In one form of the present disclosure, a method for manufacturing a surface having a plurality of slightly different patterns includes drawing a surface with a set of characters to form a pattern on the surface, and character modification. Reducing the number of shots or total drawing time through the use of technology.

  In another form of the present disclosure, a method for manufacturing a surface comprises designing a number of patterns to be formed on a surface, the patterns being slightly different, from which the characters used Determining a set of characters, providing a stencil mask having a character set, and reducing the number of shots or total drawing time by using character modification techniques.

  In another form of the present disclosure, a system for manufacturing a surface having a plurality of slightly different patterns includes a stencil mask having a collection of characters for forming a pattern on the surface, and the number of shots or total by using character modification techniques. An apparatus for reducing drawing time is disclosed.

  In one form of the present disclosure, a method for optical proximity correction of a design of a pattern on a surface comprises inputting a desired pattern for a substrate and inputting a set of characters. Are disclosed in a way that some of the characters are complex characters that can be used to form a pattern on the surface.

  In another form of the present disclosure, a method for optical proximity correction of a surface pattern design comprises inputting candidate glyphs, the glyphs are based on a predetermined character, and the glyphs are character doses. Disclosed in a manner determined using a calculation of change, character position change or character partial exposure application.

  In yet another aspect of the invention, a system for optical proximity correction of a surface pattern design comprises a desired pattern for a substrate and a set of characters, with some of the characters on the surface. It is disclosed in a system that is a complex character for forming such a pattern.

  In another form of the present disclosure, a method for fracturing, mask data preparation or proximity effect correction is disclosed, the method comprising inputting patterns to be formed on a surface, the patterns Is a slightly different variant of each other, and the method further includes selecting a set of characters, some of which are complex characters that are used to form multiple patterns, and character modification techniques. Reducing the number of shots or total drawing time by use.

  In another form of the present disclosure, a system for fracturing, mask data preparation or proximity effect correction is disclosed, the system comprising an apparatus for inputting a pattern to be formed on a surface, the pattern being slightly The system further comprises a device that selects a set of characters, some of which are complex characters used to form multiple patterns, and the set of characters is attached to a stencil mask The number of shots and the total drawing time are reduced by using the character change technique.

  These and other advantages of the present disclosure will become apparent after considering the following detailed specification in conjunction with the accompanying drawings.

1 is a diagram of a cell projection system used to manufacture a surface. FIG. It is a figure which shows the design of the pattern arrange | positioned at a board | substrate. It is a figure which shows the pattern formed in the reticle from the design shown by FIG. 2A. It is a figure which shows the pattern formed in the photoresist of a board | substrate using the reticle of FIG. 2B, and there is no optical proximity effect correction | amendment, and it is a figure which shows that an image is almost the same as the design shown by FIG. . FIG. 2B is a diagram showing an optical proximity effect corrected version of the pattern shown in FIG. 2A. FIG. 3B is a diagram showing an optical proximity effect corrected version of the pattern shown in FIG. 3A, after the reticle has been formed. It is a figure which shows the pattern formed in the photoresist of the silicon wafer using the reticle of FIG. 3B. It is the figure which showed the ideal pattern arrange | positioned on a board | substrate. It is the figure which showed two basic stencil shapes. FIG. 4B is a diagram showing two basic stencil shapes shown in FIG. 4B in the superposition method. FIG. 4D shows a pattern formed on a reticle using the overlay stencil shape shown in FIG. 4C. 4D shows a pattern formed on a substrate by using the pattern shown in FIG. 4D. FIG. FIG. 4 is a diagram showing two basic stencil shapes in a superposition scheme, where one of the stencil shapes consists of two separated squares. FIG. 5B is a diagram illustrating a pattern formed on a reticle by use of the superimposed stencil shape shown in FIG. 5A. FIG. 5B is a diagram showing a pattern formed on a substrate by using the pattern shown in FIG. 5B. It is the figure which showed the stencil shape for forming a pattern in a reticle. FIG. 6B is a diagram showing a pattern formed on a reticle by using the stencil shape shown in FIG. 6A. FIG. 6B is a diagram showing a pattern formed on a substrate by using the pattern shown in FIG. 6B. It is the figure which showed four stencil shapes used in order to form a pattern in the surface. It is the figure which showed the pattern formed in the surface by use of the stencil shape shown by FIG. 7A. It is the figure which showed the collection of the characters formed in the stencil mask. It is the figure which showed the pattern formed in the surface by use of the collection of characters shown by FIG. 8A. It is a figure showing a set of adjustment characters. Using the solid line shape and the dotted line shape, by using the character set shown in FIG. 8A and the set of adjustment characters shown in FIG. FIG. It is the figure which showed the pattern formed in the surface by use of the group of the character shown by FIG. 8A, and the adjustment character shown by FIG. 8C. It is the figure which showed the notional flow figure of how to prepare the surface used for manufacture of a board like an integrated circuit in a silicon wafer. FIG. 5 shows another conceptual flow diagram of how to prepare a surface for use in manufacturing a substrate such as an integrated circuit on a silicon wafer. It is a figure showing a set of characters. It is the figure which showed the collection of the character and the adjustment character by the change of shape. It is the figure which showed the collection of the character and the adjustment character by the change of a position. It is a figure showing a set of patterns created by changing the shape of the adjustment character. It is the figure which showed the collection of the pattern produced with the various dose amount of the adjustment character. It is the figure which showed the collection of the pattern produced with the various dose amount of the single character. It is the figure which showed the set of the pattern produced by the change of the position of an adjustment character. FIG. 5 shows a conceptual flow diagram of how to prepare a surface used for manufacturing a substrate such as an integrated circuit on a silicon wafer. It is the figure which showed the example of the glyph. It is the figure which showed the example of the parameterized glyph.

Detailed Description of Embodiments Referring to the drawings, like numerals refer to like items, and the numeral 10 in FIG. 1 identifies an embodiment of a lithography system, such as a particle beam lithography system, in which case 2 is an electron beam lithography system that employs character projection to produce a surface 12 in accordance with the present disclosure. The electron beam drawing system 10 includes an electron beam source 14 that projects an electron beam 16 toward an aperture plate 18. The plate 18 has an opening 20 formed so that the electron beam 16 can pass therethrough. As the electron beam 16 passes through the aperture 20, the electron beam is directed or refracted as an electron beam 22 toward another rectangular aperture plate or stencil mask 21 by a lens system (not shown). The stencil mask 24 has a plurality of openings 26 defined therein that define various types of characters 28. Each character 28 formed in the stencil mask 24 can be used to form a pattern on the surface 12. The electron beam 30 emerges from one of the openings 26 and is directed onto the surface 12 as a pattern 32. The surface 12 is coated with a resist (not shown) that reacts with the electron beam 30. The pattern 32 is drawn by using one shot of the electron beam drawing system 10. This reduces the overall writing time to complete the pattern 32 compared to using a variable shaped beam (VSB) projection system or method. The surface 12 can be a reticle. Thus, the surface 12 can be used in other devices or machines, such as a scanner, to transfer the pattern 32 to a silicon wafer to create an integrated circuit or chip. More generally, reticle 12 is used in other devices or machines to transfer pattern 32 to a substrate.

  As indicated above, semiconductor manufacturing and other nanotechnology manufacturing has reached the limits of optical lithography and it is difficult to transfer the ideal pattern onto the substrate. For example, FIG. 2A shows an ideal pattern 40 that represents a circuit to be formed in a resist on a substrate. If a reticle designed to have a pattern formed thereon is generated, the reticle is not a complete representation of the pattern 40. A pattern 42 that can be formed in the reticle, intended to represent pattern 40, is shown in FIG. 2B. The pattern 42 has features that are more rounded and shorter than the pattern 40. When pattern 42 is employed in the optical lithography process, pattern 44 is formed in the photoresist on the substrate, as shown in FIG. 2C. Pattern 44 is not very close to ideal pattern 40 and demonstrates why optical proximity correction is required.

  In an effort to compensate for differences between patterns 40 and 44, optical proximity correction is used. Optical proximity effect correction alters the reticle to compensate for distortions caused by optical diffraction, optical interference with adjacent shapes, and resist process effects. FIGS. 3A-3C illustrate how optical proximity correction can be employed to extend the optical lithography process to develop better versions of the pattern 44. FIG. In particular, FIG. 3A shows a pattern 50 that is a modified version of the pattern 40. The pattern 50 has serif elements 52 added to the various corners of the pattern 50 to provide extra area in an attempt to reduce optical and process effects that reduce corner sharpness. Once the pattern 50 reticle is generated, the pattern 50 may appear in the reticle as a pattern 54 as shown in FIG. 3B. When the optical proximity correction pattern 54 is used in an optical lithographic apparatus, an output pattern 56 as shown in FIG. 3C is generated. The pattern 56 is more similar to the ideal pattern 40 than the pattern 44, which is due to optical proximity effect correction. Although using optical proximity correction is useful, all patterns need to be deformed or decorated, which increases the time and cost to produce a reticle or photomask. Also, when OPC is applied, the various patterns formed on the reticle have precisely slight differences between them, which adds time and expense in the processing of the reticle. . In addition, because the number of characters required is too large, numerous minor differences or changes in the pattern make reticle creation unwieldy by using a character projection system.

  Referring to FIG. 4A, an ideal pattern 60 that is placed on a substrate, such as a contact, is shown. The ideal pattern 60 has a square shape. In an attempt to provide a reticle that transfers the pattern 60 to the substrate as closely as possible, the following steps are used. FIG. 4B shows two basic stencil shapes or characters 62, 64 that can be used to draw an ideal pattern 60 on a reticle. The stencil shape 62 is a square 66 with serifs 68 located at each corner 70, 72, 74, 76. The stencil shape 64 is an adjustment character that can be rearranged into a shape 62 for changing or changing the shape of the serif 68 at one or more of the corners 70, 72, 74, 76. For example, in FIG. 4C, stencil shape 64 is shown overlaid on corner 74 of stencil shape 62. When the stencil shapes 62 and 64 are used in a cell projection apparatus such as the electron beam drawing system 10 as shown in FIG. 1 to draw a pattern on the reticle, a pattern 78 as shown in FIG. appear. The pattern 78 has corners 80 that are more stretched or clearer than the other corners. This is because the corner 74 has changed due to the use of the stencil shape 64. The pattern 78 is on a photomask or reticle, but can be used in a conventional lithographic apparatus to transfer the pattern 78 to the substrate. For example, if the pattern 78 is an appropriate shape given an adjacent shape that affects optical proximity correction to produce the pattern 60 on the substrate as closely as possible, as shown in FIG. 4E. The pattern 82 will result in the pattern 78 being transferred to the substrate. The pattern 82 is similar to or approximate to the ideal pattern 60.

  Various other patterns can be formed using the stencil shapes 62,64. For example, two instances of shape 64 may be combined as a single character 90 that is used to form pattern 92 overlying corners 70, 74, as shown in FIG. 5A. The stencil shapes 90 and 92 are overlapping shots that can generate the pattern 94 in FIG. 5B on the reticle. If the pattern 94 on the reticle is an appropriate shape given the adjacent shape that affects optical proximity correction to produce the pattern 60 on the substrate as closely as possible to the pattern 60, the pattern 94 on the reticle is the substrate. A pattern 96 as shown in FIG. 5C appears on the substrate. The pattern 96 is substantially the same as the ideal pattern 60. It is possible and planned to change or change the dose used in the electron beam lithography system 10 to further change or adjust the various patterns formed on the reticle. As can be appreciated, the use of several stencil shapes can create multiple or diverse shapes on a reticle-like surface.

  Here, with particular reference to FIG. 12, a set of 16 characters 400, 402, 404, 406, 408, 410, 412, 414, 416, 418, 420, 422, 424, 426, 428, 430 is a character projection. Shown as characters appearing on the surface after being projected by the system. As shown by the character 400, the “0-ear” pattern on the surface is projected by the character whose design is shown as “central CP” 450 in FIG. 13 and is a square shown as “square” 452 in FIG. Project pattern of design. The “2 year” pattern as shown by the character 414 is projected by the character whose design is shown as “Year at 23” 454 in FIG. 13, and the “2 year” pattern is an example of an adjustment character. Similarly, 15 characters 402, 404, 406, 408, 410, 412, 414, 416, 418, 420, 422, 424, 426, 428, 430 projected in combination with the character 400 are on the surface, As shown in FIG. 14, 15 patterns 472, 474, 476, 478, 480, 482, 484, 486, 488, 490, 492, 494, 496, 498, 500 may be generated. The pattern 470 (FIG. 14) is created by projecting the character 400 at a specific dose. 14 patterns 472, 474, 476, 478, 480, 482, 484, 486, 488, 490, 492, 494, 496, 498, 500 can be generated on the surface from a small set of characters, slightly It is a glyph formed by a combination of two character shots, which is a large modification of different patterns. The reason that a major change may be required is optical proximity correction for the resulting projection using optical lithography when the surface is a reticle or photomask. In order to project the square 452 as shown in FIG. 13 onto the substrate, the optical proximity effect correction is necessary, so that an “O-ear” 400 (FIG. 12) needs to be formed on the reticle. However, the present disclosure is independent of the reason for requiring large changes in slightly different patterns.

  By changing the dose of the adjusting character, the deformation of the pattern that can be irradiated on the surface only through these characters is further increased. FIG. 15 shows cases 530, 532, 534, 536, 538 with varying doses at 0%, −30%, −60%, + 50% and + 100%, producing significant dimensional variations from 10 nm to 19 nm. Indicates. Further, the dose of the central character indicated by “0 Year” 400 (FIG. 12) can also be varied to produce further variations of slightly different patterns. FIG. 16 represents different shapes 550, 552, 554, 556, and 558 that can be created on the surface by varying the dose by −40%, −20%, 0%, + 25%, + 50%. Shape 560 shows the overlap of shapes 550, 552, 554, 556, 558, and also shows a slightly different pattern that can be generated by changing the dose. Each of the patterns 550, 552, 554, 556, 558 may be glyphs or patterns that are known to be available with a small number of character shot combinations. A parameterized glyph can be used as a smaller representation that has more generality for describing multiple glyphs in a single description. A pattern 560 shows that the dose amount can be a parameter for expressing a large number of glyphs in one expression. A parameterized glyph, a single description that describes all of these candidate glyphs 550, 552, 554, 556, 558, is a smaller and more flexible representation. Slightly different patterns can also be generated by illuminating different positions with the same basic pattern of adjustment characters. Referring to FIG. 17, in pattern 580 and pattern 582, the same one-ear character such as character 404 shown in FIG. 12 is arranged at different positions with respect to the zero-ear character such as character 400 in FIG. Consists of. By preparing a large number of character variants, in this case only two shots with a very large number of slightly different patterns due to variations of the central character, variations of the adjusting character, and changes in dose and relative position Can be projected onto the surface. With three or more shots, the number of available glyph patterns that can be projected onto the surface increases geometrically. Other patterns such as patterns 584, 586, 588, 590 are also shown in FIG. For example, the pattern 584 is formed by combining the character 400 (FIG. 12) with a character in the case of a standard distance with two ears using the adjustment character 412 shown in FIG. The pattern 586 is formed by combining the character 400 with a character in the case of a long distance with two ears using the adjustment character 432 of FIG. The pattern 588 is formed by combining the character 400 of FIG. 12 with the character in the case of a standard distance of 3 years using the adjustment character 424 of FIG. The pattern 590 is formed by combining the character 400 of FIG. 12 with the character in the case of a long distance with 3 ears using the adjustment character 434 shown in FIG.

  Referring now to FIG. 6A, another stencil pattern 100 that can be used in an attempt to form a pattern on a substrate, such as a silicon wafer, is similar to the ideal pattern 60 as shown in FIG. 4A. Is shown. The stencil pattern 100 includes a stencil shape 102 having a serif 104 at each corner 106, 108, 110, 112. The stencil pattern 100 also has sub-resolution assist features (SRAF) 114 disposed diagonally at each corner 106, 108, 110, 112. The stencil pattern 100 is used to form a pattern 116 on the reticle as shown in FIG. 6B. Referring now to FIG. 6C, pattern 116 is thus used to form pattern 118 on the substrate. The pattern 118 is the same as the ideal pattern 60.

  FIG. 7A shows four stencil characters 150, 152, 154, 156, which are combined to form a precise shape or pattern on the reticle as shown in FIG. 7B. Can be used for masks. In particular, the first character 150 is irradiated or projected on the reticle, then the second character 152 is irradiated, and then the third character 154 is finally the fourth character 156. The character has a curved shape, not a linear shape. In this manner, a complex pattern such as pattern 158 can be formed on the reticle. The shape in the stencil mask can be called a “character”, and the pattern formed on the reticle can be called a “glyph”. It is also possible to generate more slight deformations of the pattern, formed on the reticle by using the same stencil character, such as characters 150, 152, 154, 156, using dose control in addition to shape changes. Is possible. At different doses, multiple character combinations can be superimposed on each other to increase the shape or pattern deformation that could be generated. In addition, the position of the character can be changed to increase the shape or pattern deformation that could be generated. Since the shapes of the characters 150, 152, 154, and 156 are curvilinear, this is because particles are used to draw a glyph pattern such as the pattern 158 by irradiating or projecting the characters 150, 152, 154, and 156 on the reticle. A beam drawing system reduces the number of shots that must be used. For example, the pattern 158 can be illuminated by using only four characters 150, 152, 154, 156. On the other hand, if a linear shape is used, more shots or VSB shots must be used. As shown, the ability to use characters instead of VSB shots reduces reticle preparation time. It is also possible to use a linear shape with a curvilinear shape to form a pattern on the reticle. This feature of character projection can be used in character projection systems when projecting surfaces that require very large deformations in shape, but the number of characters that can be made available as a single element is sufficiently large There is no. The method and system combine multiple characters with partial projection variations with doses, positions, or potential overlay shots to dramatically increase the number of glyph patterns available. By having a very large number of glyphs as available patterns instead of a very limited number of characters as available patterns, more complex patterns can have a significant impact on the number of shots or drawing time. And can be projected onto the surface. Alternatively, the use of a large number of available glyphs thus allows a surface with a highly complex shape to be illuminated with a much smaller number of shots or drawing times.

  Referring now to FIG. 8A, an example of a set of characters 200 that can be placed on a stencil mask is shown. The collection of characters 200 can be used to form a pattern 202 on the reticle, as shown in FIG. 8B. The pattern 202 can be formed from one or more characters in the set of characters 200. However, in an attempt to better form an ideal pattern to be transferred onto a silicon wafer by using a reticle, an adjustment character or shot 204 as seen in FIG. 8C may further improve the resolution of the pattern 202. Can be used. FIG. 8D shows an example of a pattern 202 combined with an adjustment character 204 that can be formed in the resist of the reticle. The adjustment character 204 is represented by a dotted line, indicating that the dose of these characters 204 is smaller than the dose used to irradiate other characters 202. FIG. 8E shows a pattern 206 formed on the reticle by using a set of characters 200 and adjustment characters 204 at various doses. A limited number of characters, such as a collection of characters 200, can be used to form a plurality of differently shaped patterns or a plurality of slightly differently shaped patterns.

  FIG. 9 shows a conceptual flow diagram 250 of how to prepare a surface for use in manufacturing a substrate such as an integrated circuit on a silicon wafer. In a first step 252, a physical design such as an integrated circuit physical design is designed. This may include determining logic gates, transistors, metal layers, and other elements that are required to be found in physical designs, such as physical designs in integrated circuits. Next, in step 254, optical proximity effect correction is determined. In embodiments of the present disclosure, this may include employing a pre-computed glyph or parameterized glyph library input. This also includes, alternatively or additionally, employing in step 262 the input of a pre-designed library of characters that includes complex characters available on the stencil 260. In embodiments of the present disclosure, the OPC step 254 may also include simultaneous optimization of the number of shots or drawing time, and may also include a fracturing operation, a shot placement operation, a dose allocation operation, or A shot sequence optimization operation or other mask data preparation operation may also be included. When the optical proximity correction is completed, in step 256, the mask design is developed. In step 258, a mask data preparation process may be performed, which may include a fracturing operation, a shot placement operation, a dose assignment operation, or a shot sequence optimization. Separation programs independent of either OPC step 254 or MDP step 250, or these two steps 254 or 258, may have a limited number of stencil characters that must be present in the stencil, or different doses, positions and requirements. A program for determining a number of glyphs or parameterized glyphs that can be illuminated on a surface with a small number of shots by combining characters according to the degree of partial exposure to draw all or most on the reticle Can be included. Throughout this disclosure, it should be understood that the mask data preparation step 258 or mask data preparation does not include OPC. Combinations of OPC and some or all of the various operations of mask data preparation in one step are contemplated in this disclosure. Mask data preparation step 258 may include a fracturing operation, but may also include a pattern matching operation to match glyphs to create a mask that closely matches the mask design. Mask data preparation is to enter a pattern to be formed on the surface with several slightly different patterns, and select a set of characters to be used, a set of characters that fit a large number of patterns, stencil masks In order to reduce the number of shots or the total drawing time, a character set based on the change of the character dose, the change of the character position or the partial exposure of the character is formed within the range of the character set. A collection of slightly different patterns on the surface can be designed to produce substantially the same pattern on the substrate. Further, the set of characters can be selected from a predetermined set of characters. In one embodiment of this disclosure, the set of characters available in the stencil at step 270 that may be selected immediately during the mask drawing step 262 may be prepared for a particular mask design. In that embodiment, once mask data preparation step 258 is complete, a stencil is prepared at step 260. In another embodiment of this disclosure, a stencil may be prepared in step 260 prior to or simultaneously with MDP step 258 and may be independent of a particular mask design. In this embodiment, the character and stencil layout available at step 270 is designed at step 272 to generally output many possible mask designs 256 to incorporate slightly different patterns. The slightly different pattern is similarly output by a specific OPC program 254, a specific MDP program 258, or a specific type of design. That particular type of design is a small amount of memory on the chip design, flash memory, system, or a specific process technology designed in physical design 252, a specific cell library used in physical design 252, or mask design 256. Characterize any other common features that can form different sets of different patterns. The stencil may include a set of characters, such as a limited number of characters, including a set of adjustment characters, as determined in step 258. When the stencil is completed, the stencil is used to create a surface in a mask writing apparatus, such as an electron beam writing system. This particular step is defined as step 262. As shown in step 264, the electron beam writing system projects a beam of electrons onto the surface through the stencil to form a pattern on the surface. The completed surface can then be used in an optical lithographic apparatus, which is shown in step 266. Finally, in step 268, a substrate such as a silicon wafer is manufactured. As previously described, in step 270, the character may be provided to OPC step 254 or MDP step 258. Step 270 also provides the character to character and stencil design step 272 or glyph generation step 274. Character and stencil design step 272 provides input to stencil step 260 and character step 270. The glyph generation step 274 provides information for the glyph or parameterized glyph step 276. Also, as discussed, glyph or parameterized glyph step 276 provides information to OPC step 254 or MDP step 258.

  Referring now to FIG. 10, another conceptual flow diagram 300 of how to prepare a surface for use in the manufacture of a substrate such as an integrated circuit on a silicon wafer is shown. In a first step 302, a physical design such as an integrated circuit physical design is designed. This can be an ideal pattern that the designer wants to be transferred to the substrate. Next, in step 304, the optical proximity correction of the ideal pattern generated in step 302 is determined. This may include selecting the glyph that needs to be prepared. The optical proximity correction also comprises inputting candidate glyphs, the glyphs being based on a predetermined character, the glyphs being calculated for character dose change, character position change or character partial exposure application Is determined by using Further, the optical proximity effect correction is performed by selecting one glyph from candidate glyphs, calculating a pattern on the substrate based on the selected glyph, and an error from the calculation having a predetermined threshold value. Selecting another glyph if exceeded. The predetermined character may be from a list of geometric patterns. If the optical proximity correction is complete, the mask design is developed at step 304. Next, in step 306, a mask design is prepared. Once the mask design is prepared, further resolution enhancement of the mask design is performed in a mask data preparation step 308. The mask data preparation step 308 may include a program for determining a limited number of stencil characters that need to be present in the stencil that allow all required patterns to be drawn on the reticle. Mask data preparation also includes pattern matching that matches the glyphs to produce a mask that matches the mask design very well. Iterative pattern matching, dose assignment, and equivalence verification may also be performed, possibly including only one iteration in which a “deterministic” computation of correct-by-construction is performed. These steps help to prepare an equivalent mask design with increased resolution. As the mask resolution is increased, an equivalent mask design is generated at step 310. There are two motivations for testing that can be used to determine whether an equivalent mask design is truly equivalent to a mask design. One motivation is to pass the mask inspection. The other motivation is to confirm that if a chip or integrated circuit is manufactured, it functions properly. The strictness with respect to the pattern matching operation represents that a match can be determined by a set of equivalence criteria. The equivalence criteria can be driven, at least in part, by litho-equivalence. Liso equivalence is determined by a predetermined set of geometric rules or by a set of mathematical expressions representing coincidence, partial coincidence or inconsistency, or by performing a lithography simulation of a surface pattern design and a lithography simulation of a glyph And can be determined by comparing two results using a predetermined set of geometric rules, or by a set of mathematical expressions representing matches, partial matches or mismatches. The MDP step 308 uses a predetermined set of available characters, glyphs or parameterized glyphs to ensure that the resulting equivalent mask design 310 meets the equivalence criteria, while ensuring that the shot count or drawing Time can be optimized. In other embodiments, OPC and MDP may be combined in a verification parallel design, in which case there may be no mask design 306 generated separately from the equivalent mask design 310. The equivalent mask design can be used to prepare a stencil as shown in step 312. When the stencil is completed, the stencil is used to prepare the reticle in a mask drawing apparatus such as an electron beam drawing system. This step is identified as step 314. An electron beam lithography system projects a beam of electrons through a stencil mask to form a pattern on a surface. The surface is completed at step 316. The completed surface is then used in the optical lithographic apparatus shown in step 318 to transfer the pattern found on the surface to a substrate such as a silicon wafer to produce an integrated circuit. Finally, at step 320, a substrate such as a semiconductor wafer is produced. As described above, in step 322, the character may be provided to OPC step 304 or MDP step 308. Step 322 also provides the character to the glyph generation step 326. Character and stencil design step 324 provides input to stencil step 312 or character step 322. Character step 322 provides information to glyphs or parameterized glyph steps 328. Also, as already discussed, the glyph or parameterized glyph step 328 provides information to either the OPC step 304 or the MDP step 308.

  Referring to FIG. 18, another conceptual flow diagram 700 of how to prepare a surface to be drawn directly on a substrate such as a silicon wafer is shown. In a first step 702, a physical design, such as an integrated circuit physical design, is designed. This can be an ideal pattern that the designer wants to be transferred to the substrate. Next, in step 704, proximity effect correction (PEC) and other data preparation (DP) steps are performed to prepare input data to the board drawing apparatus, and the result of physical design is Includes many slightly different patterns. Step 704 also includes inputting candidate glyphs or parameterized glyphs from step 724, which glyphs are based on the predetermined character from step 718, and that the glyphs are character doses in glyph generation step 722. It is determined by using a calculation of change of quantity, change of shot position, or application of character partial exposure. Step 704 may also include pattern matching that matches the glyphs to create a wafer image that closely matches the physical design created in step 702. It is also possible to perform iterations of pattern matching, dose assignment, and equivalence verification, possibly including only one iteration where a “deterministic” computation of the verification parallel design is performed. The stencil is prepared at step 708 and then provided to the wafer writer at step 710. Once the stencil is complete, the stencil is used to prepare the wafer in a wafer drawing apparatus such as an electron beam drawing system. This step is identified as step 710. An electron beam lithography system projects a beam of electrons onto a surface through a stencil to form a pattern on the surface. The surface is completed at step 712. Further, at step 718, the character can be provided to the PEC and data preparation step 704. Step 718 also provides the character to glyph generation step 722. Character and stencil design step 720 provides input to stencil step 708 or character step 718. Character step 718 provides input to character and stencil design step 720. The glyph generation step 722 provides information to the glyph or parameterized glyph step 724. A glyph or parameterized glyph step 724 provides information to the PEC and data preparation step 704. Step 710 is potentially processed using the methods some of which have been described in connection with FIGS. 9 and 10 and others that have been outlined above with reference to FIG. It may include repetitive applications required to process each layer that have been processed and others processed using any other wafer drawing method for generating integrated circuits on silicon wafers.

  FIG. 11 shows various other basic template shapes or characters 350, 352, 354, 356, 358, 360, 362 that can be used as a collection of stencil characters to form various patterns on the reticle. When using character projection, the stencil character can be slightly changed in three ways. The first method is to change the shape and the size of the character. For example, various character projections can be used where a single character can change by partially exposing a portion of the character. The second method is to slightly change the dose when irradiating a predetermined shape and size of the character. The “dosing” of the particle projection shot is the shutter speed, that is, the length of time for which a predetermined shot is projected onto the surface of the reticle. “Dose correction” is a processing step in which the dose amount for any given character projection shot is slightly changed, for example, for proximity effect correction (PEC). In this particular embodiment, in combination with additional or other dose corrections, the dose is deliberately changed to slightly change the size and shape of the character projected onto the surface of the reticle, thereby allowing the pattern or Form a glyph. It is also possible to change the pattern irradiated to the reticle by using multiple overlay shots of characters 350, 352, 354, 356 to generate a number of different patterns or glyphs. The pattern or glyph can be a linear shape, a substantially linear shape, a straight line or a curvilinear shape. In addition, it is also contemplated that the dose may be altered in combination with the use of overlay characters to produce even more various patterns or glyphs. Also, a set of stencil characters may be used in a VSB shot, which is an example of a simple character, in order to form more patterns or glyphs on the surface. VSB shots and characters can be combined with assigned doses to produce a great many different patterns or glyphs. A third method for slightly changing the stencil character involves a change of position. Characters 358, 360, and 362 show three variations of the same character position. By changing the dose in addition to the character's geometric shape and the relative position of the character with respect to each other, the number of mask image fragments that can be immediately illuminated from a predetermined set of characters in the character projection is made multiple. A large number of glyphs requiring a small number of characters may be available to project complex patterns with a reduced number of shots and drawing time.

  Through the use of a set of characters, complex shapes including concatenated or separated groups of linear shapes, shapes combining any angle ends, and shapes containing arbitrary curves can be formed. Arbitrary curves include circles, semicircles and quarter circles. A set of characters for character projection is designed and included in a stencil implemented in a particle beam projection system for drawing a reticle. The optical proximity correction system can be used to select a character projection character combination that potentially includes VSB shots that change the potential change dose and angle of the partial projection to produce multiple patterns. A set of characters is either in the case of a specific design or, more generally, in the case of a design with a certain commonality and a future design, such as a specific semiconductor manufacturing technology node. In particular, it can be designed in advance. The optical proximity correction system can resolve each of the superimposed characters with various doses. This allows complex shapes to be formed on the reticle.

  It is also possible that the optical proximity correction system starts with a large library of pre-computed or pre-calculated glyphs. The optical proximity correction system can therefore attempt to use as many available glyphs as possible in performing an optical proximity correction transfer from the original physical design of the integrated circuit to the reticle design. The glyphs are each marked with an associated shot number and drawing time optimal value so that the optical proximity correction system, mask data preparation system or some independent program selects a lower shot number or drawing time, The number of shots or drawing time can be optimized. This optimization is a greedy way in which each glyph is chosen to optimize what is the best glyph to select the number of shots or drawing time in a particular order. Can be performed, selecting glyphs to match patterns, or exchanging glyph selections performed in an iterative optimization scheme such as simulated annealing that optimizes overall shot count or drawing time obtain. Some desired patterns that can be formed on the reticle will still remain unmatched by any available glyph, and such patterns may have the need to be formed by the use of VSB shots.

  Referring to FIG. 19, examples of glyphs 1000, 1002, 1004, 1006 that can be used by optical proximity correction, fracturing, proximity effect correction, or other steps of mask data preparation are shown. These glyphs 1000, 1002, 1004, 1006 may not be generated by the same character combination, or they may also be glyphs generated from four different characters. Regardless of how the glyph is created, the glyph represents a possible pattern known to be a possible pattern of the surface that can be generated with a small number of shots or drawing times. Each glyph may be associated with a specification for the characters required to generate the glyph, a partial exposure instruction for each character, a projection request dose for each character, and a relative position of the character.

  FIG. 20 shows an example of parameterized glyphs 1010 and 1012. The glyph 1010 illustrates a general shape described with dimensional specifications that can be varied, where the length X differs between 10 and 25 by a value in length units. Glyph 1012 illustrates a similar general shape in a more restrictive manner, where length X is a specific value, eg, only one of 10, 15, 20, or 25. I can take it. The parameterized glyphs 1010 illustrate that these descriptions allow for many candidate glyphs that are not possible with the unparameterized glyph enumeration.

  An example description of a parameterized glyph for glyph 1010 may be shown as follows:

  An example description of a parameterized glyph for glyph 1020 may be shown as follows:

  These description examples show which parameter value is `` where ((x = 10) or (x = 15) or (x = 20) or (x = 25)) '' or `` where ((x = 10) or ( (x> 10) and (x <25)) or (x = 25)) ”based on parameters that give rise to a logical test that determines whether certain criteria are met. There are many other ways to describe parameterized glyphs. Another example illustrating the construction method is shown below.

  Although the specification has described in detail in connection with particular embodiments, those skilled in the art may readily correspond to variations, modifications, and equivalents of these embodiments in reaching the above understanding. It will be clear. These and other modifications and variations of the proposed system and method for manufacturing reticles using character projection lithography are within the spirit and scope of the present subject matter as specifically described by the appended claims. It can be realized by those skilled in the art without departing. Moreover, those skilled in the art will appreciate that the above description is illustrative only and is not intended to be limiting. Accordingly, the subject matter is intended to cover such modifications and variations as fall within the scope of the appended claims and their equivalents.

Claims (84)

A method for manufacturing a surface, wherein the surface has a plurality of slightly different patterns, the method comprising:
Using a set of characters on a stencil mask to form the pattern on the surface;
Reducing the number of shots or total drawing time by using character change techniques.   The method of claim 1, wherein the character change technique includes changing a character dose.   The method of claim 1, wherein shots from a plurality of characters in the set of characters overlap.   The method of claim 1, wherein the character change technique includes changing a character position.   The method of claim 1, wherein the character modification technique includes applying a partial exposure of a character in the set of characters.   The method of claim 1, wherein the surface is a reticle.   The method of claim 6, wherein the slightly different pattern on the surface produces a substantially identical pattern on the substrate.   The method of claim 7, wherein an equivalence criterion determines whether the patterns on the substrate are substantially identical.   The method of claim 8, wherein the equivalence criterion is based on lithography simulation.   The method of claim 1, wherein the surface is a substrate.   The method of claim 1, further comprising using character projection lithography. Further comprising designing a plurality of patterns to be formed on the surface, the patterns being slightly different,
Designing a set of characters to be used from the plurality of patterns;
The method of claim 1, further comprising providing a stencil mask having the set of characters. A system for manufacturing a surface, wherein the surface has a plurality of slightly different patterns, the system comprising:
A stencil mask having a set of characters for forming the pattern on the surface;
And a device for reducing the number of shots or total drawing time through the use of character modification techniques.   The system of claim 13, wherein the character change technique includes changing a character dose.   The system of claim 13, wherein shots from multiple characters in the set of characters overlap.   The system of claim 13, wherein the character change technique includes changing a character position.   The system of claim 13, wherein the character modification technique includes applying a partial exposure of a character in the set of characters. A method for manufacturing an integrated circuit, the integrated circuit having a surface with a surface having a plurality of slightly different patterns, the method comprising:
Using a set of characters on a stencil mask to form the pattern on the surface;
Reducing the number of shots or total drawing time by using character change techniques.   The method of claim 18, wherein the character change technique includes changing a character dose.   The method of claim 18, wherein shots from multiple characters in the set of characters overlap.   The method of claim 18, wherein the character change technique includes changing a character position.     The method of claim 18, wherein the character modification technique includes applying a partial exposure of a character in the set of characters.   The method of claim 18, further comprising using character projection lithography. Further comprising designing a plurality of patterns to be formed on the surface, the patterns being slightly different,
Designing a set of characters to be used from the plurality of patterns;
The method of claim 18, further comprising: preparing a stencil mask having the set of characters. A method for manufacturing an integrated circuit using an optical lithography process, wherein the optical lithography process uses a plurality of reticles having slightly different patterns, the method comprising:
Using a set of characters on a stencil mask to form the pattern on the reticle;
Reducing the number of shots or total drawing time by using character change techniques.   26. The method of claim 25, wherein the character change technique includes changing a character dose.   26. The method of claim 25, wherein shots from multiple characters in the set of characters overlap.   26. The method of claim 25, wherein the character change technique includes changing a character position.   26. The method of claim 25, wherein the character change technique includes applying partial exposure of characters in the set of characters.   26. The method of claim 25, wherein slightly different patterns on the reticle produce substantially identical patterns on the substrate.   The method of claim 30, wherein an equivalence criterion determines whether the patterns on the substrate are substantially identical.   32. The method of claim 31, wherein the equivalence criterion is based on lithography simulation.   26. The method of claim 25, further comprising using character projection lithography. Further comprising designing a plurality of patterns to be formed on the reticle, the patterns being slightly different from each other;
Designing a set of characters to be used from the plurality of patterns;
26. The method of claim 25, further comprising providing a stencil mask having the character set. A method for optical proximity correction of a design comprising a set of patterns on a surface, wherein the surface is used to transfer the set of patterns to a substrate in an optical lithography process, the method comprising:
Inputting a desired pattern for the substrate;
Inputting a set of characters, wherein some of the characters are complex characters that can be used to form the pattern on the surface.   36. The method of claim 35, further comprising calculating a change in character dose, character position or character partial exposure in the set of characters.   36. The method of claim 35, further comprising determining a number of shots or a total drawing time, wherein the number of shots or the total drawing time is reduced.   36. The method of claim 35, further comprising overlaying a plurality of characters in the set of characters to form the pattern on the surface.   36. The method of claim 35, wherein the subset of the pattern of the surface comprises patterns that are slightly different from each other.   40. The method of claim 39, wherein the slightly different pattern on the surface produces a pattern on the substrate that is substantially the same.   41. The method of claim 40, wherein equivalence criteria determine whether the patterns on the substrate are substantially identical.   42. The method of claim 41, wherein the equivalence criterion is based on lithography simulation.   A method for optical proximity correction of a design comprising a set of patterns on a surface, wherein the surface is used to transfer the set of patterns to a substrate in an optical lithography process, the method inputs candidate glyphs The glyph is based on a character in a predetermined set of characters, and the glyph calculates a change in character dose, a change in character position, or application of partial exposure of the character in the predetermined set of characters. Determined using the method. Selecting a glyph from the candidate glyphs;
Calculating a pattern to be transferred to the substrate based on the selected glyph;
44. The method of claim 43, further comprising: selecting another glyph from the candidate glyph when an error from the computing step exceeds a predetermined threshold.   44. The method of claim 43, wherein the candidate glyph is a parameterized glyph. A method of generating glyphs,
Obtaining a predetermined set of characters as the basis of the glyph;
Calculating a character dose change, a character position change or a character partial exposure application in the predetermined set of characters to create an additional glyph.   47. The method of claim 46, wherein the glyph is a parameterized glyph.   47. The method of claim 46, wherein the created glyph includes a subset of glyphs, and the glyph in each of the subsets includes a plurality of slightly different patterns.   47. The method of claim 46, further comprising calculating a plurality of overlay shots from one or more characters in the predetermined set of characters. A system for optical proximity correction of a design comprising a set of patterns on a surface, wherein the surface is used to transfer the set of patterns to a substrate in an optical lithography process, the system comprising:
A desired pattern for the substrate;
A set of characters, wherein some of the characters are complex characters for forming some of the patterns on the surface.   51. The system of claim 50, further comprising an apparatus for calculating a change in character dose, character position, or character partial exposure in the character set.   51. The system of claim 50, further comprising an apparatus for determining a shot number or a total drawing time, wherein the shot number or the total drawing time is reduced.   51. The system of claim 50, wherein a plurality of characters in the set of characters overlap.   A system for optical proximity correction of a design comprising a set of patterns on a surface, wherein the surface is used to transfer the set of patterns to a substrate in an optical lithography process, the system inputs candidate glyphs The glyph is based on a character in a predetermined set of characters, and the glyph calculates a change in character dose, a change in character position or application of partial exposure of the character in the predetermined set of characters. Determined using the system.   A glyph is selected from the candidate glyph, the transferred pattern on the substrate is computed based on the selected glyph, and from the candidate glyph when an error from the computing step exceeds a predetermined threshold 55. The system of claim 54, wherein another glyph is selected. A system for generating glyphs,
A device for obtaining a predetermined set of characters as the basis of the glyph;
A system for calculating an additional glyph by calculating a character dose change, a character position change or a character partial exposure application in the set of predetermined characters.   57. The system of claim 56, wherein the glyph is a parameterized glyph.   57. The system of claim 56, wherein the created glyph includes a subset of glyphs, and the glyph in each of the subsets includes a plurality of slightly different patterns.   57. The system of claim 56, wherein a plurality of shots from one or more characters in the predetermined set of characters are overlaid to generate at least one of the glyphs. A method for fracturing, mask data preparation or proximity effect correction,
Inputting a pattern to be formed on the surface, wherein the subsets of the patterns are slightly different variants of each other;
Further comprising selecting a set of characters used to form a plurality of patterns, some of the characters being complex characters;
A method in which the number of shots or total drawing time is reduced by using character modification techniques.   61. The method of claim 60, wherein the slightly different pattern on the surface produces a substantially identical pattern on a substrate.   64. The method of claim 61, wherein an equivalence criterion determines whether the patterns on the substrate are substantially identical.   64. The method of claim 62, wherein the equivalence criterion is based on a lithography simulation.   The method of claim 60, wherein the set of characters is predetermined.   65. The method of claim 64, further comprising inputting candidate glyphs, wherein the glyphs are based on the predetermined set of characters.   66. The method of claim 65, wherein the glyph is a parameterized glyph.   66. The method of claim 65, further comprising determining which glyphs are used to match one or more of the input patterns.   66. The method of claim 65, further comprising optimizing fracturing, mask data preparation, or proximity effect correction based on the number of shots or writing time.   66. The method of claim 65, wherein the glyph includes a subset of glyphs, each of the glyph subsets including a plurality of slightly different patterns.   61. The method of claim 60, wherein the character change technique is changing a character dose.   61. The method of claim 60, wherein the character change technique is changing a character position.   61. The method of claim 60, wherein the character modification technique is to apply one partial exposure of the set of characters.   61. The method of claim 60, wherein the character change technique is to superimpose characters. A system for fracturing, mask data preparation, or proximity effect correction,
Comprising a device for inputting a pattern to be formed on the surface, the subsets of the patterns being slightly different variants of each other;
Further comprising a device for selecting a set of characters used to form a plurality of patterns, some of the characters being complex characters;
The system, wherein the character set is adapted to a stencil mask and the number of shots or total drawing time is reduced by using character modification techniques.   75. The system of claim 74, wherein the slightly different pattern on the surface produces a substantially identical pattern on a substrate.   76. The system of claim 75, wherein equivalence criteria determine whether the patterns on the substrate are substantially identical.   The system of claim 76, wherein the equivalence criterion is based on lithography simulation.   75. The system of claim 74, further comprising an apparatus for entering candidate glyphs and determining which glyphs to use to match one or more of the input patterns.   79. The system of claim 78, further comprising an apparatus for optimizing fracturing, mask data preparation, or proximity effect correction based on shot number or writing time.   79. The system of claim 78, wherein the glyph includes a subset of glyphs, and each of the glyph subsets includes a plurality of slightly different patterns.   75. The system of claim 74, wherein the character change technique is changing a character dose.   75. The system of claim 74, wherein the character change technique is to change a character position.   75. The system of claim 74, wherein the character modification technique is to apply one partial exposure of the set of characters.   75. The system of claim 74, wherein the character change technique is to superimpose characters.

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