JP5459647B2 - Pattern simulation method, apparatus thereof, and program thereof - Google Patents

Description

  The present invention relates to a pattern simulation method for virtually simulating a substrate pattern formed by exposure on a substrate, an apparatus therefor, and a program therefor.

  In general, 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, and switch elements is formed by forming a thin film such as a conductor or a 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 this process is exposed in an exposure process through a reticle having a predetermined pattern, and the photoresist exposed in this exposure process is developed in a development process. It is formed by repeatedly removing the exposed thin film by removing the photoresist in the etching process.

  In recent years, with the enlargement of the screen of a liquid crystal display device, an exposure process by 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 sequentially through a corresponding mask. In the exposure processing by this divided exposure method, there is a region on the dividing line having a width of 3 to 10 μm called a multiple exposure region between regions exposed for each shot. In the region on the dividing line, the exposure is performed a plurality of times, that is, twice.

  In general, a reticle as a photomask used in the exposure processing by the divided exposure method is designed using a CAD system. Then, as a reticle pattern design procedure in this divided exposure method, after designing the pattern of the size of the liquid crystal display panel of the liquid crystal display device so as to satisfy the design standard, this pattern is changed to the size of the reticle and this Divide to fit the 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 medium of the CAD system. Then, based on these design data, a reticle pattern corresponding to the design pattern of the liquid crystal display panel and the dividing line is formed, and a photomask is completed by adding a shading band pattern covering a shading area called a shading band. .

  The photomask 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, the coordinate data on the substrate to be exposed, and the like. The specified range on the reticle is designated on the substrate. Expose the area.

  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, simulation is performed to confirm how the substrate is exposed using CAD data such as reticle data and exposure data.

One of the simulation methods is to create a predicted pattern that predicts the shape after exposure, take the difference between the predicted pattern and the reticle pattern, and overlap or calculate the calculation result of the difference pattern difference with the predicted pattern. A method of simulating a substrate pattern is known (for example, see Patent Document 1).
JP 2004-265386 A

  There is a method of preparing a substrate pattern separately as one method of checking and comparing whether the simulation result matches the substrate pattern.

  However, since the substrate pattern and the predicted pattern are created by combining a plurality of designed data, if the data becomes complicated, the number of patterns increases, and the calculation time when the above simulation is performed becomes longer. There is a problem.

  The present invention has been made in view of these points, and an object of the present invention is to provide a pattern simulation method, an apparatus thereof, and a program thereof capable of speeding up a comparison operation between a substrate pattern and an expected pattern.

The present invention is based on reticle data indicating a reticle pattern for each divided region obtained by dividing a pattern to be formed on a substrate into a plurality of areas, and exposure data indicating a position on the substrate where the reticle pattern is shot. A pattern simulation method for simulating a substrate pattern formed by exposure on a substrate, the substrate pattern creating step for creating the substrate pattern by combining a plurality of substrate pattern data having at least one pattern cell, and the substrate In the substrate pattern created in the pattern creation step, when the same pattern cell overlaps, the computation substrate pattern creation step for creating the computation substrate pattern using only any one of the pattern cells ; A plurality having at least one reticle cell In the predicted pattern creating step for creating a predicted pattern expected when the substrate pattern is formed on the substrate by the reticle data and the exposure data, and in the predicted pattern created in the predicted pattern creating step, When the same reticle cell is overlapped, a calculation predicted pattern creating step of creating a calculation predicted pattern using only one of the reticle cells , the calculation substrate pattern, and the calculation predicted pattern And a comparison step for calculating and comparing.

The present invention also provides reticle data indicating a reticle pattern for each divided region obtained by dividing a pattern to be formed on a substrate into a plurality of areas, and exposure data indicating where on the substrate the reticle pattern is shot. A pattern simulation apparatus for simulating a substrate pattern formed by being exposed on the substrate by a substrate pattern creating means for creating the substrate pattern by combining a plurality of substrate pattern data having at least one pattern cell; When the same pattern cell is overlapped in the substrate pattern created by the substrate pattern creating means, the computation substrate pattern creation is created using only one of the pattern cells. Means and at least one reticle cell A predicted pattern creating means for creating a predicted pattern expected when the substrate pattern is formed on the substrate by a plurality of the reticle data and the exposure data, and the predicted pattern created by the predicted pattern creating means When the same reticle cell is overlapped, a calculation predicted pattern generation means for generating a calculation predicted pattern using only one of the reticle cells , the calculation substrate pattern, and the calculation predicted pattern Comparing means for calculating and comparing.

Further, the present invention provides reticle data indicating a reticle pattern for each divided area obtained by dividing a pattern to be formed on a substrate into a plurality of areas, and exposure data indicating where on the substrate the reticle pattern is shot. A pattern simulation program for simulating a substrate pattern that is exposed and formed on the substrate by combining a plurality of substrate pattern data having at least one pattern cell to create the substrate pattern; and When the same pattern cell is overlapped in the substrate pattern created in this substrate pattern creation step, the computation substrate pattern creation is created using only one of the pattern cells. Step and at least one An expected pattern creating step for creating an expected pattern when the substrate pattern is formed on the substrate by a plurality of the reticle data having a reticle cell and the exposure data, and the predicted pattern creating step When the same reticle cell is overlapped in the predicted pattern, a predicted process pattern creation step for creating a predicted pattern for calculation using only one of the reticle cells, and the calculation substrate pattern and the calculation And a comparison step for calculating and comparing the predicted pattern for use.

If the same pattern cell overlaps in the created substrate pattern, an arithmetic substrate pattern is created using only one of the pattern cells, and the same reticle cell is created in the created predicted pattern. If they overlap, a predicted pattern for calculation is created using only one of these reticle cells .

  According to the present invention, it is possible to reduce the amount of calculation when calculating and comparing the calculation substrate pattern and the calculation predicted pattern, and to speed up the comparison calculation.

  An embodiment of the present invention will be described below with reference to FIGS.

  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 which is a liquid crystal display element as a display element, and a designed substrate pattern. The computer system includes a pattern simulation program for simulating the above and layout verification software for comparing the simulation pattern simulated by the pattern simulation program with the design pattern.

  Here, the liquid crystal panel is configured by interposing a liquid crystal layer between the array substrate and a counter substrate disposed opposite to the array substrate. Scanning lines, signal lines, thin film transistors, etc. are disposed on the array substrate. Various circuit patterns are formed. A plurality of liquid crystal panels are formed in a matrix on a rectangular flat plate large-sized glass substrate as a substrate.

  The computer also includes a hard disk as storage means, memory as temporary storage means, substrate pattern creation means, predicted pattern creation means, calculation substrate pattern creation means, calculation predicted pattern creation means, comparison means, and simulation pattern creation means. Each of the control means such as a CPU having the above functions as functions is provided.

  Further, the substrate pattern is a substrate designed based on an array cell, that is, a pattern cell, which is predetermined CAD data for each divided region obtained by dividing a design pattern designed in advance corresponding to a pattern to be created on a large format glass substrate. Created by combining pattern data. Here, for example, as shown in FIG. 2, the substrate pattern 1 includes substrate pattern data A1 and A2 in which the pattern cell a2 or the pattern cell a3 is designed based on the pattern cell a1, and substrate pattern data A3 that is the pattern cell a1. It is created in combination with. In FIG. 2, only one divided region of the substrate pattern 1 is illustrated, but other portions of the substrate pattern 1 are similarly created.

  In addition, the expected pattern is a reticle cell which is CAD data on the reticle for each divided region obtained by dividing a design pattern designed in advance corresponding to the entire pattern to be formed on the large-sized glass substrate into a plurality along the boundary line. The reticle data designed on the basis is combined with exposure data indicating the position on the substrate to be shot. Here, for example, as shown in FIG. 3, the predicted pattern 2 is created from the reticle data 3 based on the reticle cell b1 or the reticle pattern B1 or B2 in which the reticle cell b3 is designed based on the reticle cell b1, and the exposure data 4. Is done. In FIG. 3, only one divided region of the predicted pattern 2 is illustrated, but other portions of the predicted pattern 2 are similarly created.

  A reticle is a photomask for developing and etching a liquid crystal panel by separately exposing it. For example, the reticle has a reticle pattern that exposes the upper left side, upper right side, lower left side, and lower right side of each liquid crystal panel. doing.

  Further, the exposure data includes data indicating the exposure area of the reticle divided into a lattice and data indicating where on the large glass substrate is exposed by these reticles. This exposure data is input for each exposure or only the coordinate movement amount is input if the same exposure is repeated. The exposure data is numerical data that is decomposed and inputted for each single shot as matrix input data. Further, the exposure data is stored in a readable manner on a hard disk of a computer, for example, and a reticle pattern at a predetermined position on a large-sized glass substrate is exposed by an exposure machine (not shown).

  The pattern simulation program creates a simulation pattern that simulates a substrate pattern formed by exposure on a large glass substrate by an exposure device based on the exposure data and reticle data.

That is, in the pattern simulation method of the present embodiment executed by the pattern simulation program, as shown in the flowchart of FIG. 1, first, a plurality of substrate pattern data is created by the substrate pattern creating means while the computer is activated. A substrate pattern 1 is created by combining A1 to A3 (step 1 (substrate pattern creation process)).

Next, when the same pattern cell is overlapped in the substrate pattern 1 created in step 1 by the computation substrate pattern creation means, one pattern cell is excluded from the computation target , in other words, the same pattern. The calculation substrate pattern 5 is created using only one pattern cell of the cells (step 2 (calculation substrate pattern creation step)).

  At this time, the determination criteria for the same pattern cell are, for example, the cell name, the reference point when viewed from the top cell, the cell arrangement angle when viewed from the top cell, and the inversion information (inversion from the top cell). None, X-axis reversal, Y-axis reversal, XY-axis reversal), magnification when viewed from the top cell, X direction repeat count, Y direction repeat count, X axis direction pitch, Y axis direction pitch, cell direction rotation angle If all 10 items match, it is determined that they are the same.

Here, since three pattern cells a1 are overlapped, two of the pattern cells a1 are excluded from the calculation target and are used as the calculation substrate pattern 5 . In other words, the calculation substrate pattern 5 is created using only one of the three identical pattern cells a1 that overlap .

  When it is determined that there are no overlapping pattern cells, the substrate pattern 1 and the calculation substrate pattern 5 are the same.

  On the other hand, the predicted pattern creating means creates a predicted pattern 2 by combining a plurality of reticle cells b1, b2 or a plurality of reticle patterns B1, B2 having reticle cells b1, b3 (step 3 (predicted pattern creating step)).

Next, when the same reticle cell overlaps in the predicted pattern 2 created in step 3 by the predicted pattern creation means for calculation, one of the reticle cells is excluded from the calculation target , in other words, out of the same reticle cell. The prediction pattern 6 for calculation is created using only one of these reticle cells (step 4 (prediction pattern for calculation calculation step)).

  At this time, the determination criteria for the same reticle cell are, for example, the cell name, the reference point when viewed from the top cell, the cell placement angle when viewed from the top cell, and the inversion information when viewed from the top cell (no inversion) , X-axis inversion, Y-axis inversion, XY-axis inversion), and those in which all five items of magnification when viewed from the highest cell match are determined to be the same.

Here, since the two reticle cells b1 are overlapped, one of the reticle cells b1 is excluded from the calculation target, and is set as the predicted pattern 6 for calculation . In other words, the prediction pattern 6 for calculation is created using only one of the two overlapping reticle cells b1 .

  When it is determined that there are no overlapping reticle cells, the predicted pattern 2 and the predicted pattern 6 for calculation are the same.

  Furthermore, the comparison means calculates and compares the calculation substrate pattern 5 created in step 2 and the calculation prediction pattern 6 created in step 4, and compares the calculation substrate pattern 5 and the calculation prediction pattern 6. A difference pattern showing the difference between them is calculated (step 5 (comparison process)).

  Then, the difference pattern is calculated with the expected pattern 2 (including superposition) by the simulation pattern creation means to create a simulation pattern for simulating the substrate pattern 1 (step 6 (simulation pattern creation step)).

As described above, according to the above embodiment, when the same pattern cell a1 is overlapped in the substrate pattern 1 created in the substrate pattern creation step, only one of the pattern cells a1 is selected. If the same reticle cell b1 is overlapped in the predicted pattern 2 created in the predicted pattern creation process, the calculation forecast is made using only one of the reticle cells b1. By creating the pattern 6, the calculation target pattern when calculating and comparing the calculation substrate pattern 5 and the predicted calculation pattern 6 is reduced, the calculation amount (the number of calculation) is reduced, and this comparison is performed. Calculation can be speeded up.

  Further, in the comparison calculation, the calculation substrate pattern 5 and the calculation predicted pattern 6 are calculated to create a difference pattern indicating the difference between them, and the difference pattern is calculated with the prediction pattern 2 to calculate the substrate pattern 1. The simulation time can be shortened by creating a simulation pattern that simulates the above.

Incidentally, in the embodiment described above, simulation pattern creating step (simulation pattern creating means), based on the result of comparison in the comparison step (comparison means), may create a simulation pattern.

  Steps 1 and 2 and steps 3 and 4 may be reversed in order, or may be performed in parallel.

  Furthermore, the pattern simulation method of the above-described embodiment can be used for simulation of any pattern other than the liquid crystal panel.

  Furthermore, it is possible to record a pattern simulation program in which the pattern simulation method is a program operable by a computer 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 the board | substrate pattern creation process and the board | substrate pattern creation process for a calculation of a pattern simulation method same as the above. It is explanatory drawing which shows the predicted pattern creation process and the predicted pattern creation process for a calculation of a pattern simulation method same as the above.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate pattern 2 Expected pattern 3 Reticle data 4 Data for exposure 5 Substrate pattern for calculation 6 Expected pattern for calculation
a1, a2, a3 Pattern cell
A1, A2, A3 PCB pattern data
b1, b2, b3 reticle cells

Claims (6)

Exposure on the substrate by reticle data indicating a reticle pattern for each divided area obtained by dividing a pattern to be formed on the substrate into a plurality of areas, and exposure data indicating where the reticle pattern is shot on the substrate A pattern simulation method for simulating a substrate pattern to be formed,
A substrate pattern creating step for creating the substrate pattern by combining a plurality of substrate pattern data having at least one pattern cell;
When the same pattern cell is overlapped in the substrate pattern created in this substrate pattern creation step, the computation substrate pattern creation is created using only one of the pattern cells. Process,
An expected pattern creating step for creating an expected pattern when the substrate pattern is formed on the substrate by a plurality of the reticle data having at least one reticle cell and the exposure data;
In the predicted pattern created in the predicted pattern creating step, when the same reticle cell is overlapped, a predicted pattern for calculating pattern for creating a predicted pattern for calculation using only one of the reticle cells; and ,
A pattern simulation method comprising: a comparison step of calculating and comparing the calculation substrate pattern and the calculation expected pattern. In the comparison step, the calculation substrate pattern and the calculation expected pattern are calculated to create a difference pattern indicating the difference between them,
The pattern simulation method according to claim 1, further comprising a simulation pattern creation step of creating a simulation pattern for simulating the substrate pattern by calculating the difference pattern with the predicted pattern. Exposure on the substrate by reticle data indicating a reticle pattern for each divided area obtained by dividing a pattern to be formed on the substrate into a plurality of areas, and exposure data indicating where the reticle pattern is shot on the substrate A pattern simulation apparatus for simulating a substrate pattern to be formed,
A substrate pattern creating means for creating the substrate pattern by combining a plurality of substrate pattern data having at least one pattern cell;
When the same pattern cell is overlapped in the substrate pattern created by the substrate pattern creating means, the computation substrate pattern creation is created using only one of the pattern cells. Means,
An expected pattern creating means for creating an expected pattern when the substrate pattern is formed on the substrate based on a plurality of the reticle data having at least one reticle cell and the exposure data;
In the predicted pattern created by the predicted pattern creating means, when the same reticle cell overlaps, the predicted pattern creation means for computation creates a predicted pattern for computation using only one of the reticle cells. ,
Comparing means for calculating and comparing the calculation substrate pattern and the calculation prediction pattern. The comparison means calculates the calculation substrate pattern and the calculation prediction pattern and creates a difference pattern indicating a difference between them,
The pattern simulation apparatus according to claim 3, further comprising a simulation pattern creating unit that computes the difference pattern with the predicted pattern and creates a simulation pattern for simulating the substrate pattern. Exposure on the substrate by reticle data indicating a reticle pattern for each divided area obtained by dividing a pattern to be formed on the substrate into a plurality of areas, and exposure data indicating where the reticle pattern is shot on the substrate A pattern simulation program for simulating a substrate pattern formed by
A substrate pattern creating step for creating the substrate pattern by combining a plurality of substrate pattern data having at least one pattern cell;
When the same pattern cell is overlapped in the substrate pattern created in this substrate pattern creation step, the computation substrate pattern creation is created using only one of the pattern cells. Steps,
An expected pattern creating step of creating an expected pattern expected when the substrate pattern is formed on the substrate based on the plurality of reticle data having at least one reticle cell and the exposure data;
In the predicted pattern created in this predicted pattern creating step, when the same reticle cell is overlapped, a predicted pattern for computing pattern creating step for creating a predicted pattern for calculation using only one of these reticle cells ; ,
A pattern simulation program comprising: a comparison step for calculating and comparing the calculation substrate pattern and the calculation expected pattern. In the comparison step, the calculation substrate pattern and the calculation prediction pattern are calculated to create a difference pattern indicating the difference between them,
The pattern simulation program according to claim 5, further comprising a simulation pattern creating step for creating a simulation pattern for simulating the substrate pattern by calculating the difference pattern with the predicted pattern.

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