JP2008216646A - Pattern simulating method, device, and program, and medium recording this program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pattern simulating method reducing the errors caused by the pattern size differences in the multiple exposure area when comparing the substrate pattern with an expected pattern. <P>SOLUTION: A compensation exposure pattern is formed by expanding or contracting the patterns in the multiple exposure area by using an AND pattern obtained by ANDing a pattern obtained by expanding or contracting along the boundaries of the divided areas of the multiple exposing area pattern having reticle patterns overlapping one another with the patterns adjoining the multiple exposure area. A simulation pattern is formed by processing the difference pattern between the compensation exposure pattern and expected pattern, and the designing pattern. When checking the drawing by comparing the substrate pattern with the expected pattern, a simulation pattern can be formed with reduced errors caused by the pattern size differences in the multiple exposure area. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a pattern simulation method, an apparatus thereof, a program thereof, and a medium on which the same is recorded, which forms a simulation pattern to be detected by comparing a substrate pattern with an expected pattern.

  In general, a liquid crystal panel as a liquid crystal display element used in a liquid crystal display device includes wiring such as scanning lines and signal lines, electrodes such as pixel electrodes, or switching elements such as thin film transistors.

  Each of these wirings, electrodes, switching elements, and the like is formed by forming a thin film such as a conductor or dielectric on a substrate in a film forming process, and applying a photoresist on the thin film formed in this film forming process. The photoresist applied in the application step is exposed in the exposure step through a reticle having a predetermined pattern, and the photoresist exposed in the exposure step is developed in the development step. It is formed by repeatedly removing the exposed thin film by removing the photoresist.

  In recent years, with the enlargement of the screen of a liquid crystal display device, an exposure process using a division exposure method is used in which a substrate is divided into a plurality of regions and the photoresist in each region is exposed through a corresponding mask.

  In the exposure processing by this divided exposure method, there is an area on a dividing line having a predetermined width called a multiple exposure area between areas exposed for each shot, and the area on this dividing line is exposed a plurality of times.

  In general, a reticle as a photomask used in exposure processing by such a division exposure method is designed using a CAD system. As a reticle pattern design procedure in this divided exposure method, a liquid crystal panel size pattern is designed so as to satisfy a design standard, and then this pattern is divided so as to match the size and number of reticles. . At this time, the dividing line for dividing the pattern is formed along a place where there is no influence on characteristics.

  Furthermore, design data corresponding to the design pattern for the preliminary dividing line of the liquid crystal display panel is stored and stored in the storage means of the CAD system. Then, based on these design data, a reticle pattern corresponding to the design pattern of the liquid crystal panel and the dividing line is formed, and a reticle is completed by adding a light shielding band pattern covering a light shielding area called a light shielding band.

  The reticle is exposed on the substrate using coordinate data called exposure data. The exposure data includes the range of the exposure area on the reticle and data indicating the reference center point, and the coordinate data on the substrate to be exposed. The specified range on the reticle is specified on the substrate. The exposed area is exposed.

  In such an exposure process using the divided exposure method, there may be a mistake that the arrangement of the light shielding pattern is wrong or the numerical value of the exposure data is wrong. For this reason, using CAD data such as reticle data and exposure data, it is confirmed by simulation how the pattern is exposed on the substrate.

  Then, as a method for checking the pattern formed by designing the arrangement of the reticle pattern and the numerical values of the exposure data, for example, a substrate pattern is prepared separately as a design pattern. It is conceivable to compare whether they match.

As one of such simulation methods, a method is known in which a predicted pattern that predicts a substrate pattern after exposure is created, and a difference pattern between the predicted pattern and the reticle pattern is calculated to calculate the difference pattern (for example, (See Patent Document 1).
JP 2004-265386 A

  However, in the exposure processing by the divided exposure method, there are multiple exposure regions that are exposed in an overlapping manner, and the size of the overlapping exposed pattern changes. For this reason, since the reticle pattern is designed in advance in consideration of changes in the size of the pattern due to overlapping exposure, the multiple exposure area is designed when the predicted pattern and the reticle pattern are compared. However, there are problems that many errors are displayed due to the difference in pattern size.

  The present invention has been made in view of the above points, and is a simulation pattern that suppresses the occurrence of errors due to the difference in pattern size in the multiple exposure region when the substrate pattern is compared with the predicted pattern that is predicted. An object of the present invention is to provide a pattern simulation method, an apparatus, a program thereof, and a medium recording the same.

  The present invention provides reticle data indicating a reticle pattern for each divided region obtained by dividing a design pattern designed in advance corresponding to an entire pattern to be formed on a substrate into a plurality along a predetermined boundary line, and the reticle pattern. A pattern simulation method for forming a simulation pattern that simulates a substrate pattern formed by being exposed on the substrate with exposure data indicating a position on the substrate to be shot, and predicting the substrate pattern An expected pattern creating step for creating an expected pattern based on the reticle data and the exposure data, and an expansion / contraction pattern obtained by expanding / contracting a pattern of a multiple exposure region where the reticle patterns overlap each other along a boundary line between the divided regions And a pattern adjacent to the multiple exposure area A A corrected exposure pattern obtained by correcting the exposure pattern when the substrate pattern is formed on the substrate by the reticle data and the exposure data by expanding / contracting the pattern of the multiple exposure region using an AND pattern obtained by D calculation. A corrected exposure pattern creation step to create, a difference pattern calculation step to calculate a difference pattern by taking the difference between the predicted pattern and the corrected exposure pattern, and the difference pattern and the design pattern to process the substrate pattern A simulation pattern creating step for creating the simulation pattern to be simulated.

  Further, the present invention provides reticle data indicating a reticle pattern for each divided region obtained by dividing a design pattern designed in advance corresponding to an entire pattern to be formed on a substrate into a plurality along a predetermined boundary line; A pattern simulation apparatus for forming a simulation pattern by simulating a substrate pattern formed by exposure on the substrate according to exposure data indicating a position on the substrate at which a reticle pattern is shot, wherein the substrate pattern is Expected pattern creation means for creating a predicted pattern based on the reticle data and the exposure data, and a pattern of a multiple exposure region where the reticle patterns overlap each other along the boundary line between the divided regions Stretch pattern and pattern adjacent to the multiple exposure area A corrected exposure pattern obtained by correcting the exposure pattern when the substrate pattern is formed on the substrate by the reticle data and the exposure data by expanding and contracting the pattern of the multiple exposure region using an AND pattern obtained by ANDing A corrected exposure pattern creating means for creating a difference pattern calculating means for calculating a difference pattern by taking a difference between the predicted pattern and the corrected exposure pattern; and processing the difference pattern and the design pattern to obtain the substrate pattern And a simulation pattern creating means for creating the simulation pattern.

  Further, the present invention provides reticle data indicating a reticle pattern for each divided region obtained by dividing a design pattern designed in advance corresponding to an entire pattern to be formed on a substrate into a plurality along a predetermined boundary line; A pattern simulation program for forming a simulation pattern by simulating a substrate pattern formed by exposure on the substrate according to exposure data indicating a position on the substrate where the reticle pattern is shot. A predicted pattern creating step for creating a predicted pattern that is predicted based on the reticle data and the exposure data, and a pattern in a multiple exposure region where the reticle patterns overlap each other along a boundary line between the divided regions Adjacent to the stretch pattern and the multiple exposure area The exposure pattern when the substrate pattern was formed on the substrate was corrected by the reticle data and the exposure data by expanding / contracting the pattern of the multiple exposure region using an AND pattern obtained by ANDing with the pattern to be corrected. A corrected exposure pattern creating step for creating a corrected exposure pattern, a difference pattern calculating step for calculating a difference pattern by taking a difference between the predicted pattern and the corrected exposure pattern, and processing the difference pattern and the design pattern A simulation pattern creating step for creating the simulation pattern for simulating the substrate pattern.

  Then, the pattern of the multiple exposure region is obtained by using an AND pattern obtained by ANDing the expansion / contraction pattern obtained by expanding / contracting the pattern of the multiple exposure region where the reticle patterns overlap with each other along the boundary line between the divided regions and the pattern adjacent to the multiple exposure region. Is expanded and contracted to create a corrected exposure pattern in which the size of the multiple exposure area of the exposure pattern is corrected, and a difference pattern between the corrected exposure pattern and the predicted pattern and the design pattern are processed to generate a simulation pattern.

  According to the present invention, it is possible to form a simulation pattern in which an error due to a difference in pattern size in a multiple exposure region is prevented when inspection is performed by comparing a substrate pattern with an expected pattern.

  The configuration of an embodiment of the present invention will be described below with reference to the drawings.

  The pattern simulation apparatus according to the present embodiment includes a computer (not shown), for example, CAD software which is pattern layout software used for designing a substrate pattern of an array substrate of a liquid crystal panel 1 which is a liquid crystal display element as a display element, and a designed substrate. A computer system includes a pattern simulation program for simulating a pattern and layout verification software for comparing a simulation pattern simulated by the pattern simulation program with a design pattern.

  Here, the liquid crystal panel 1 is configured by interposing a liquid crystal layer between an array substrate and a counter substrate disposed opposite to the array substrate. On the array substrate, scanning lines, signal lines, thin film transistors, etc. The various circuit patterns are formed. The liquid crystal panel 1 is formed in a matrix shape, for example, four on a rectangular flat plate large-sized glass substrate 2 as a substrate.

  In addition, the computer has a hard disk as a storage means, a memory as a temporary storage means, an expected pattern creation means, a corrected exposure pattern creation means, a difference pattern calculation means, a simulation pattern creation means, etc. Each is provided.

  Further, a divided area A1, in which a design pattern 3 designed in advance corresponding to the entire pattern to be formed on the large-sized glass substrate 2 is divided into a plurality of areas along the boundary lines L1, L2, L3, L4, L5, and L6. The CAD data composed of the reticle patterns on the reticles 5, 6, 7 and 8 for each of A2, A3 and A4 is the reticle data 9.

  Reticles 5 to 8 are photomasks for separately exposing and developing or etching the liquid crystal panel 1. The reticles 5 to 8 have a reticle pattern that exposes, for example, the upper left side, the upper right side, the lower left side, and the lower right side of each liquid crystal panel 1.

  Further, the exposure data 11 indicating where on the large-sized glass substrate 2 the reticle pattern such as the reticles 5 to 8 is shot is data indicating the exposure areas of the reticles 5 to 8 divided in a lattice pattern, and These reticles 5 to 8 are provided with data indicating where on the large glass substrate 2 is exposed. The exposure data 11 is input for each exposure or only the amount of coordinate movement is input if the same exposure is repeated. The exposure data 11 is numerical data that is decomposed and inputted for each single shot as matrix input data.

  The exposure data 11 is stored in a readable manner on a hard disk of a computer, for example, and a reticle pattern at a predetermined position on the large glass substrate 2 is exposed by an exposure machine (not shown).

  The pattern simulation program creates a simulation pattern 15 that simulates a substrate pattern formed by exposure on the large format glass substrate 2 by an exposure machine based on the exposure data 11 and the reticle data 9.

  That is, the pattern simulation method according to the present embodiment executed by the pattern simulation program is based on the reticle data 9 and the exposure data 11 in a state where the computer is started as shown in the flowchart of FIG. To create an expected pattern 21 (step 1 (predicted pattern creating process)).

  Specifically, the predicted pattern 21 is created by sequentially cutting out this area in each shot area on the reticles 5 to 8 and sequentially arranging patterns for all shots on the large glass substrate 2 according to the exposure data 11. .

  Next, a correction exposure pattern 23 is created by correcting the exposure pattern 22 when the substrate pattern is formed on the large format glass substrate 2 by the reticle data 9 and the exposure data 11 (step 2 (correction exposure pattern creation step)).

  In this correction, as shown in FIGS. 3 to 14, the pattern P of each multiple exposure region (double exposure region) Ap in which the reticle patterns of the reticles 5 to 8 overlap each other is divided between the divided regions A1 to A4. The pattern of the multiple exposure area Ap using AND patterns Pa1 and Pa2 obtained by ANDing the expansion / contraction pattern PΔx expanded and contracted along the boundary lines L1 and L3 (L4 and L6) and the patterns P1 and P2 adjacent to the multiple exposure area Ap Stretch P.

  Specifically, it is determined whether the pattern P of the multiple exposure area Ap is extended or contracted. For example, when the pattern P of the multiple exposure area Ap is extended as shown in FIG. 3, as shown in FIG. The expansion / contraction pattern PΔx is created by increasing the pattern P by a predetermined Δx along the boundary lines L1, L3 (L4, L6).

  Next, as shown in FIG. 5, AND patterns Pa1 and Pa2 are created by performing an AND operation on the expansion / contraction pattern PΔx and the patterns P1 and P2 adjacent to the pattern P.

  Further, as shown in FIG. 6, the pattern P of the multiple exposure area Ap is reduced along the boundary lines L1, L3 (L4, L6) by Δd1 where the pattern P protrudes from the patterns P1, P2. An expansion / contraction pattern PΔd1 is created.

  Further, as shown in FIGS. 7 and 8, parallel patterns Pp1, Pp2, Pp3, which are differential data projected from each side of the expansion / contraction pattern PΔd1 by Δd1 parallel to the boundary lines L1, L3 (L4, L6), Pp4 is created, and the parallel patterns Pp1 to Pp4 that are in contact with the AND patterns Pa1 and Pa2 are selected. 7 and 8, the parallel patterns Pp1 and Pp2 are selected.

  Thereafter, as shown in FIG. 9, a correction pattern Pr1 obtained by reducing the pattern P is formed by using the selected parallel patterns Pp1 and Pp2 and the expansion / contraction pattern PΔd1.

  For example, when the pattern P of the multiple exposure area Ap is contracted as shown in FIG. 10, this pattern P is reduced with respect to the adjacent patterns P3 and P4 as shown in FIG. The expansion / contraction pattern PΔd2 enlarged along the boundary lines L1, L3 (L4, L6) is created.

  Next, as shown in FIG. 12, the expansion / contraction pattern PΔd2 and the patterns P3 and P4 adjacent to the pattern P are ANDed to create AND patterns Pa3 and Pa4 which are difference data.

  Further, as shown in FIGS. 13 and 14, by removing the AND patterns Pa3 and Pa4 from the expansion / contraction pattern PΔd2, a correction pattern Pr2 obtained by extending the pattern P is formed.

  Then, by performing each of the above processes over the entire multiple exposure area Ap, a corrected exposure pattern 23 is created by correcting the exposure pattern 22 when the substrate pattern is formed on the large-sized glass substrate 2 as shown in FIG.

  Returning to FIG. 1, the difference pattern 24 is calculated by taking the difference between the predicted pattern 21 created in step 1 and the corrected exposure pattern 23 created in step 2 (step 3 (difference pattern calculation step)).

  Furthermore, the simulation pattern 15 that simulates the substrate pattern is created by superimposing or calculating the difference pattern 24 calculated in the above step 3 on the design pattern 3 of the substrate pattern (step 4 (simulation pattern creation step)).

  Then, the simulation pattern 15 created in step 4 is compared with the predicted pattern 21 using predetermined layout verification software, and a difference is detected as an error.

  At this time, since the simulation pattern 15 is optimized by correcting the size of the pattern P in the multiple exposure region Ap, it is possible to avoid occurrence of an unnecessary error due to the difference in size.

  Specifically, when the size of the pattern P in the multiple exposure area Ap is extended, the parallel patterns Pp1 and Pp2 are combined with the contracted expansion / contraction pattern PΔd1, and the size of the pattern P in the multiple exposure area Ap is combined. Is shrunk, the pattern P in the multiple exposure area Ap can be easily and reliably corrected by separating the AND patterns Pa3 and Pa4 from the stretched pattern PΔd2.

  And since the generation | occurrence | production of the unnecessary error at the time of the comparison with the prediction pattern 21 and the simulation pattern 15 can be avoided in this way, the time which inspection work requires can be reduced.

  In the above embodiment, the division of the design pattern 3 is not limited to four divisions.

  In addition, the pattern simulation method of the above-described embodiment can be used for simulation of an arbitrary pattern other than the liquid crystal panel.

  It is also possible to record the simulation program on an optical disk, a magnetic disk or other medium so as to be readable by a computer, and automatically operate the computer.

It is a flowchart which shows the pattern simulation method of one embodiment of this invention. It is explanatory drawing which shows a pattern simulation method same as the above. It is explanatory drawing which expands and shows the pattern which the multiple exposure area | region of the correction exposure pattern creation process of the pattern simulation method same as the above extended. It is explanatory drawing which shows the state which extended the pattern of the multiple exposure area | region of a correction exposure pattern creation process same as the above along the boundary line. It is explanatory drawing which shows the state which produced the AND pattern of the correction exposure pattern creation process same as the above. It is explanatory drawing which shows the state which shrunk along the boundary line the pattern of the multiple exposure area | region of a correction exposure pattern creation process same as the above. It is explanatory drawing which shows the state which produced the parallel pattern from the expansion / contraction pattern of a correction exposure pattern creation process same as the above. It is explanatory drawing which shows the state which selected the parallel pattern of a correction exposure pattern creation process same as the above. It is explanatory drawing which shows the state which produced the correction pattern by the selected parallel pattern and expansion / contraction pattern of the correction exposure pattern creation process same as the above. It is explanatory drawing which expands and shows the pattern which the multiple exposure area | region of the correction exposure pattern creation process same as the above shrunk. It is explanatory drawing which shows the state which extended the pattern of the multiple exposure area | region of a correction exposure pattern creation process same as the above along the boundary line. It is explanatory drawing which shows the state which produced the AND pattern of the correction exposure pattern creation process same as the above. It is explanatory drawing which shows the state except an AND pattern from the expansion / contraction pattern of a correction exposure pattern creation process same as the above. It is explanatory drawing which shows the state which produced the correction pattern of a correction exposure pattern creation process same as the above.

Explanation of symbols

2 Large format glass substrate 3 Design pattern 9 Reticle data
11 Exposure data
15 Simulation pattern
21 Expected patterns
22 Exposure pattern
23 Corrected exposure pattern
24 Difference pattern
A1, A2, A3, A4 divided area
Ap Multiple exposure area
L1, L3, L4, L6 Boundary lines PΔd1, PΔd2, PΔx Stretch pattern
Pa1, Pa2, Pa3, Pa4 AND pattern

Claims (4)

Reticle data indicating a reticle pattern for each divided region obtained by dividing a design pattern designed in advance corresponding to the entire pattern to be formed on the substrate into a plurality along a predetermined boundary line, and the reticle pattern on the substrate A pattern simulation method for forming a simulation pattern by simulating a substrate pattern formed by exposure on the substrate with exposure data indicating a position to be shot,
An expected pattern creating step for creating an expected pattern for predicting the substrate pattern based on the reticle data and the exposure data;
The multiple exposure region using an AND pattern obtained by ANDing an expansion / contraction pattern obtained by expanding / contracting the pattern of the multiple exposure region where the reticle patterns overlap with each other along a boundary line between the divided regions and a pattern adjacent to the multiple exposure region. A correction exposure pattern creating step for creating a correction exposure pattern by correcting the exposure pattern when the substrate pattern is formed on the substrate by the reticle data and the exposure data by expanding and contracting the pattern,
A difference pattern calculation step of calculating a difference pattern by taking the difference between the predicted pattern and the corrected exposure pattern;
A pattern simulation method comprising: a simulation pattern creating step of creating the simulation pattern for processing the difference pattern and the design pattern to simulate the substrate pattern. Reticle data indicating a reticle pattern for each divided region obtained by dividing a design pattern designed in advance corresponding to the entire pattern to be formed on the substrate into a plurality along a predetermined boundary line, and the reticle pattern on the substrate A pattern simulation apparatus for forming a simulation pattern by simulating a substrate pattern formed by exposure on the substrate by exposure data indicating a position to be shot,
An expected pattern creating means for creating an expected pattern for predicting the substrate pattern based on the reticle data and the exposure data;
The multiple exposure region using an AND pattern obtained by ANDing an expansion / contraction pattern obtained by expanding / contracting the pattern of the multiple exposure region where the reticle patterns overlap with each other along a boundary line between the divided regions and a pattern adjacent to the multiple exposure region. A corrected exposure pattern creating means for creating a corrected exposure pattern by correcting an exposure pattern when the substrate pattern is formed on the substrate by the reticle data and the exposure data,
Difference pattern calculation means for calculating a difference pattern by taking the difference between the predicted pattern and the corrected exposure pattern;
A pattern simulation apparatus comprising: a simulation pattern creating unit that creates the simulation pattern for processing the difference pattern and the design pattern to simulate the substrate pattern. Reticle data indicating a reticle pattern for each divided region obtained by dividing a design pattern designed in advance corresponding to the entire pattern to be formed on the substrate into a plurality along a predetermined boundary line, and the reticle pattern on the substrate A pattern simulation program for forming a simulation pattern by simulating a substrate pattern formed by exposure on the substrate with exposure data indicating a position to be shot,
An expected pattern creating step for creating an expected pattern for predicting the substrate pattern based on the reticle data and the exposure data;
The multiple exposure region using an AND pattern obtained by ANDing an expansion / contraction pattern obtained by expanding / contracting the pattern of the multiple exposure region where the reticle patterns overlap with each other along a boundary line between the divided regions and a pattern adjacent to the multiple exposure region. A correction exposure pattern creating step for creating a corrected exposure pattern by correcting the exposure pattern when the substrate pattern is formed on the substrate by the reticle data and the exposure data,
A difference pattern calculation step for calculating a difference pattern by taking the difference between the predicted pattern and the corrected exposure pattern;
A pattern simulation program comprising: a simulation pattern creating step for creating the simulation pattern for processing the difference pattern and the design pattern to simulate the substrate pattern. A medium on which a pattern simulation program according to claim 3 is recorded so as to be readable by a computer.

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