JP2002312417A - Verification method for photomask pattern data with additional graphic - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a verification method for photomask pattern data with additional graphic. SOLUTION: Whether square graphics are formed in a region which is apart from each graphic of design data by a predetermined distance and in which there is no graphic while the square graphics are two-dimensionally arranged at a predetermined pitch in X and Y directions, respectively, or not is verified for the photomask pattern data with additional graphic composed of square graphics for uniformizing graphic density in the design data and provided with a plurality of additional graphics in this verification method for the photomask pattern data with the additonal graphic. This method comprises (a) additional pattern lack region data preparation processing for preparing the pattern data indicating only the region lacking square graphic of the photomask pattern data with additional graphic and (b) overlapped part data preparation processing for applying logic AND graphic processing to the pattern data obtained by applying oversize processing to square graphics by a predetermined value by which square graphics are mutually linked for the pattern data obtained by excluding graphics of design data from the photomask pattern data with the additional graphic and the design data to prepare the pattern data indicating only an overlapped part of both pattern data.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention belongs to the field of design data processing for processing semiconductor design data. More specifically, the present invention relates to data processing for flattening a processing layer of a wafer in semiconductor manufacturing.

[0002]

2. Description of the Related Art In recent years, various LSIs represented by ASICs have been increasingly required to have higher integration and higher functionality due to the trend toward higher performance and lighter, thinner and smaller electronic devices. In semiconductor manufacturing, it has been required to form a processed layer of a wafer more flatly in terms of quality. USP5, as one of the techniques for flattening a processing layer and an insulating layer of a wafer in semiconductor manufacturing,
Nos. 597 and 668 disclose a photomask used in the manufacture of semiconductors in which an additional pattern (hereinafter, also referred to as an additional figure) other than wiring is arranged. Here, the significance of the additional pattern will be briefly described based on FIG. For example, as shown in FIGS. 5A and 5B, a process including a pattern 511 of a pattern portion 510 with a dense pattern density (also referred to as a graphic pattern or a graphic) and a pattern 512 of a pattern portion with a coarse pattern density. Layer (wiring layer)
The thickness of the deposited layer (insulating layer) deposited thereon is shown in FIG.
(A) As shown in FIG. 5 (b), while the pattern changes greatly in accordance with the pattern density, as shown in FIG. 5 (b) (a), an additional pattern 531 is added to make the pattern density uniform. In the case of a layer, the thickness of the deposited layer (insulating layer) deposited thereon becomes uniform as shown in FIG. 530 is an additional pattern unit. 5 (a) (b), FIG. 5 (b)
5B is a cross-sectional view showing the concept of a wafer process in semiconductor manufacturing, and FIG. 5A and FIG.
(A is the E1 side of FIG. 5A and FIG.
(B) It is the figure seen from E2 side of (b). In general, when patterning such a deposited layer directly or furthermore on a processing layer (also a deposited layer) deposited thereon, the better the flatness of the deposited layer on the wafer surface during transfer, the better. It is known that the transfer accuracy from the photomask to the wafer is good. In the end, the transfer accuracy from the photomask to the wafer can be increased by forming a treatment layer with uniform pattern density.

Generally, a polysilicon layer,
By repeatedly depositing an insulating layer, a wiring layer, and an insulating layer, the final wafer manufacturing process is completed.However, since the polysilicon and the wiring layer are deposited only in the portion where the pattern exists in the design data, the pattern is Depending on the presence or absence of irregularities, irregularities occur on the processed wafer surface. Since the insulating layer and the wiring layer are sequentially deposited, the unevenness difference between a portion having no pattern and a portion having the pattern gradually increases. With the miniaturization of the pattern shape on the wafer, the allowable range of this unevenness difference has been narrowed.

The above-described data with an additional figure for producing a photomask for generating an additional pattern in a wafer processing layer has been conventionally produced by a producing method shown in FIG. S610 to S640 are processing steps. Hereinafter, a method of creating the pattern data with additional graphics shown in FIG. 6 will be described with reference to an example shown in FIG. In step S610 for creating an additional graphic area in FIG. 6, first, an area in which an additional pattern is to be arranged is determined. Dp in FIG.
Indicates a figure (also called a circuit pattern or a figure pattern) in the design data DP. The minimum distance between the graphic dp and the additional graphic is set as dist so that the graphic dp does not contact the additional graphic (also referred to as an additional pattern). After creating a graphic NA (not shown) in which the graphic dp is oversized by sizing graphic processing, the graphic NA is subtracted from the entire design data area by logical NOT graphic processing,
Area data AD having an additional graphic area ad for arranging the additional graphic is created. (FIG. 7B) Subsequently, in step S620 of generating an additional pattern in the entire area in FIG. 6, additional graphic data in which additional graphics dt are arranged in an array shape over the entire area ad (also simply referred to as additional graphic data). Create a DT. (FIG. 7C) Usually, rectangles are two-dimensionally arranged. Next, the logical product of the area data AD and the additional graphic data DT is obtained by logical AND graphic processing, and pattern data including the additional graphic only in the additional graphic area ad is obtained. (FIG. 7
((D), S630) In the pattern data obtained by the logical AND graphic processing, a missing additional graphic (also referred to as a minute additional graphic) dd is generated. Next, step S of deleting the missing additional graphic in FIG.
In 640, since small figures can be a problem in photomask manufacture and wafer manufacture, undersizing and oversizing are sequentially performed by sizing figure processing to obtain pattern data obtained by removing missing additional figures dd from pattern data. . (FIG. 7 (e)). Next, final pattern data with additional graphics FP0 is obtained from the pattern data shown in FIG. 7E and the original design data DP by the logical OR graphic calculation processing. (FIG. 7F, S650) The graphic dp of the design data and the additional graphic dt of the pattern data shown in FIG. 7E are matched. The pattern data with additional figure FP0 is data for producing a photomask.

However, with respect to the data for producing a photomask produced in this way, depending on the original pattern data, when a missing portion is generated in the additional pattern or when the additional pattern is determined based on the original figure. In some cases, they were not at a distance, which was a problem. In particular, high precision is required, and OPC (Optical Proxim
This is a problem with respect to original graphic data including (i.

[0006]

As described above, the additional pattern data obtained by the conventional additional pattern data generation method shown in FIG. 6 is used when a missing portion is generated in the additional pattern or when the additional pattern There is a case where they are not separated from each other by a predetermined distance, which is required. The present invention is intended to cope with this, and is to provide a method for verifying photomask pattern data with an additional pattern. More specifically, an attempt is made to extract, from photomask pattern data with an additional pattern, a portion where the additional pattern is missing, and a portion where the additional pattern is not separated from the original graphic by a predetermined distance.

[0007]

According to the present invention, there is provided a method for verifying photomask pattern data with an additional figure, comprising a plurality of additional figures each comprising a square figure for making the figure density uniform in design data. The rectangular figure is formed in a region where there is no figure at a predetermined distance from each figure in the design data with respect to the photomask pattern data, and the rectangular figure is two-dimensionally arranged at a predetermined pitch in each of the X direction and the Y direction. A method of verifying whether or not there is an additional figure, comprising: (a) removing the additional figure from the photomask pattern data with the additional figure;
For pattern data obtained by oversizing the design data by a predetermined value, and for pattern data obtained by removing the design data figure from the photomask pattern data with the additional figure, square figures After performing logical OR graphic processing on the pattern data obtained by oversizing by a predetermined connected value and obtaining composite data, the obtained composite data and all area data representing the entire area of the design data are converted into A logical NOT graphic processing to generate pattern data representing only an area where the rectangular pattern of the photomask pattern data with the additional graphic is missing; and (b) a photo with the additional graphic. For the pattern data obtained by removing the design data figure from the mask pattern data, the square figure is oversampled by a predetermined value that connects the square figures. And performing a logical AND graphic process on the pattern data obtained by the overlap processing and the design data, and performing an overlapping portion data creating process of creating pattern data representing only the overlapping portion of the two pattern data. Is what you do. In the above description, the photomask pattern data with an additional figure with a rectangular additional figure includes, in order, (a) a pattern in which the graphic of the design data is oversized by a predetermined size from the entire area data representing the entire area of the design data. By subtracting the data by the logical NOT graphic processing, additional graphic layout area data AD representing an area where an additional graphic is to be generated is generated. Additional graphic layout area data generation processing; (b) additional graphic layout area data AD; A logical AND graphic processing is performed on the additional graphic pattern data DT in which the rectangular graphic is two-dimensionally arranged at a predetermined pitch in the X direction and the Y direction over the entire area corresponding to the entire area of the design data. Processing and (c) logical AN
An undersize process and an oversize process are sequentially performed on the pattern data obtained by the D graphic processing, and from the pattern data obtained by the logical AND graphic processing,
Deletion processing for deleting the missing additional graphic in a state where the rectangular graphic is missing, (d) combining the design data and the pattern data obtained by the deletion processing, and forming the photomask pattern data with the rectangular additional graphic The overlapping part extraction processing is a pattern data obtained by oversizing the pattern data obtained by the deletion processing by a predetermined value and the design data. And logical pattern processing to extract pattern data representing only the overlapping portion of the two pattern data. The additional graphic obtained by the additional graphic lacking area data creation processing is An error part is represented by synthesizing pattern data representing only the missing area and pattern data representing only the overlapping part obtained by the overlapping part data creation processing. It is characterized in that the tongue data. Here, the error portion refers to a missing portion where the additional graphic is missing, and a portion where the additional graphic is not separated from the original data graphic by a predetermined distance. In addition, here, “oversize processing of a rectangular figure by a predetermined value that connects the rectangular figures” means “oversize that can fill a gap between rectangular figures when the rectangular figures are normally arranged. It means oversizing by the amount.

Here, the logical operation of a graphic represented by graphic data will be briefly described with reference to FIG. As shown in FIG. 4A, when a rectangular figure (pattern) A and a figure (pattern) B are represented in the data area Da, the corresponding logical product (A) of the figure A and the figure B is represented.
ND), logical OR of graphic A and graphic B (OR), inversion of graphic B (also called Inverse or NOT (B))
Are represented as black portions in FIGS. 4B, 4C, and 4D, respectively. The actual processing content is already widely known and will not be described here.

[0009]

According to the method for verifying photomask pattern data with an additional figure of the present invention,
It is possible to provide a method for verifying photomask pattern data with additional figures. More specifically, it is possible to extract, from the photomask pattern data with an additional graphic, a portion where the additional graphic is missing, and a portion where the additional graphic is not separated from the original graphic by a predetermined distance. For pattern data obtained by oversizing the design data by a predetermined value, and for pattern data obtained by removing the design data figure from the photomask pattern data with the additional figure, square figures Logical OR graphic processing is performed on pattern data obtained by oversizing by a predetermined connected value, and combined data is obtained. After that, the obtained combined data is obtained by oversizing by a predetermined value. By performing logical NOT graphic processing on the pattern data and the entire area data representing the entire area of the design data, pattern data representing only the area where the rectangular figure of the photomask pattern data with the additional figure is missing is created. As a result, it is assumed that a missing portion where the additional graphic is missing can be extracted, and from the photomask pattern data with the additional graphic, By performing a logical AND graphic process on the pattern data obtained by performing oversize processing on the pattern data excluding the total data graphic by a predetermined value that connects the additional graphics with the additional graphic and the design data, Pattern data representing only the overlapping portion of the two pattern data is created, so that a portion where the additional graphic is not separated from the original graphic by a predetermined distance can be extracted.

Then, the pattern data representing only the area where the additional graphic is missing, obtained by the additional graphic missing area data creation processing, and the pattern data representing only the overlapping part obtained by the overlapping part data creation processing, By synthesizing the data to form pattern data representing an error portion, the confirmation is made more practical.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described. FIG. 1 is a flowchart showing an example of processing of an embodiment of a method for verifying photomask pattern data with an additional graphic according to the present invention, and FIG. 2A is a photomask pattern data with an additional graphic (FIG. 1). FIG. 2B is a diagram showing a part of the composite data (150 in FIG. 1).
3A is a diagram showing an area corresponding to FIG. 2A, and FIG. 3A is a diagram showing data obtained by removing a figure of design data from photomask pattern data with an additional figure. (B) is a diagram showing oversized data. In FIG. 1, a broken line portion 191 indicates an additional graphic missing area process, and a dashed line 192 indicates a poorly-spaced portion extraction process. S11 to S28 in FIG. 1 are processing steps. 1, 2, and 3, reference numeral 110 denotes photomask pattern data with an additional figure, 120 denotes design data, and 120A
Is a figure (of design data), 120a is a figure position, 121
Is oversize data, 130 is additional figure data, 1
30A is an additional figure, 130a is a figure position, 131 is oversized data, 132 is oversized data, 1
32A is an overlapping part, 140 is all area data, 150 is synthetic data, 151 is a missing part, 160 is an additional figure missing area data, 170 is an overlapping part data, 180 is an error part data, and 191 is an additional figure missing area data creation processing. Reference numeral 192 denotes an overlapping portion data creation process (also referred to as a defective interval portion extracting process).

An embodiment of a method for verifying photomask pattern data with an additional figure according to the present invention will be described with reference to FIG. In this example, an additional figure (FIG. 2) composed of a square figure for making the figure density uniform
130A), the square figure is placed in the X direction and the Y direction in a region where there is no figure at a predetermined distance from each figure in the design data 120 with respect to the photomask pattern data 110 with additional figures provided with a plurality of Verify whether or not they are formed in a two-dimensional array at a predetermined pitch,
This is a method for verifying photomask pattern data with an additional figure.
The additional graphic missing area extraction processing 191 for extracting only the area where the rectangular graphic is absent (additional graphic missing area data creation processing) 191, the graphic of the design data of the photomask pattern data 110 with the additional graphic, and the additional graphic Are performed to perform an interval defective portion extraction process (overlap portion data creation process) 192 for extracting an interval defective portion that is not separated by a predetermined interval or more.

First, an additional graphic missing area extracting process 19
1 will be described. First, oversize data 121 obtained by oversizing the design data 120 (S12) by a predetermined value WD1 (S13) with respect to the design data 120 (S12) obtained by removing the additional figure from the photomask pattern data 110 (S11) with the additional figure. (S14) and pattern data obtained by removing the figure of the design data 120 from the photomask pattern data 110 with the additional figure (additional figure data 130, S15)
Is a predetermined value WD that connects the rectangular figures to each other.
2 is oversized (S16), and the obtained pattern data 131 (S17) is added to the logical OR graphic processing (S16).
18) to obtain composite data 150. (S19) When a part of the photomask pattern data 110 with the additional graphic is in the state shown in FIG. 2A, the composite data 150 in the corresponding area is as shown in FIG. 2B. Reference numeral 151 denotes a blank portion of the graphic, which indicates a portion where the additional graphic is missing. When creating the composite data 150, the design data 120 is oversized by a predetermined value WD1, but within a predetermined distance WD1 from each figure of the design data 120, an area where no additional figure exists is added. This is for accurately extracting the pattern missing part.

Next, the obtained synthesized data 150 and the entire area data 140 representing the entire area of the design data (S20).
Are subjected to a logical NOT graphic process (S21) to obtain additional graphic missing area data 160. (S22) Thereby, the additional graphic missing area is extracted as a graphic. It is a figure which reversed FIG.2 (b). (Not shown) If necessary, the extracted additional graphic missing area data 16
Further, pattern data (not shown) oversized with 0 is obtained.

Next, a description will be given of the interval defective portion extraction processing 192. First, photomask pattern data 1 with an additional figure
10 (S11), the additional graphic data 130 (S15) excluding the graphic of the design data 120 (S12) is subjected to oversize processing (S23) by a predetermined value WD3 that connects the additional graphic with the additional graphic. Oversize data 132 is obtained. (S24) The oversized data 132 may be used as the oversized data 131 in the additional graphic missing area extraction processing. FIG. 3A shows a part of the additional graphic data 130. 130A is an additional graphic, and a graphic position (area surrounded by a dotted line) 120a indicates a graphic position of the corresponding design data 120. Additional graphic data 13
0 is oversized by a predetermined value WD3 because of a predetermined distance WD3 from each figure in the design data 120.
If there is an additional graphic existing within the range, the additional graphic is to reach the graphic position of the design data 120. FIG. 3B shows an area of the oversize data 132 corresponding to FIG.
Each additional graphic in (a) is oversized, and only a part reaches the graphic position 120a. FIG. 3 (b)
132A is a figure of the oversize data 132,
An overlapping portion of the design data with the graphic position 120a is shown.

Next, the obtained oversized data 1
32 and the design data 120 are subjected to logical AND graphic processing. (S25) As a result, it is possible to obtain overlapping portion data 170 (S26) representing only the overlapping portion of both pattern data. That is, an interval defective portion where the graphic of the design data of the photomask pattern data 110 with the additional graphic and the additional graphic are not separated from each other by a predetermined interval or more is extracted as an overlapping portion.

Further, a logical OR graphic process is performed on the extracted additional graphic lacking area data 160 and the overlapping part data 170 (S27), and the extracted locations are combined by both data.
Error part data 180 indicating an error part is obtained. (S2
8) In this example, a necessary error part can be extracted from the additional graphic lacking area data 160, the overlapping part data 170, and the error part data 180.

[0018]

As described above, the present invention makes it possible to provide a method for verifying photomask pattern data with an additional figure (also referred to as an additional figure pattern). In detail, for a photomask pattern data with an additional graphic, a verification method that can extract a missing part where the additional graphic is missing and a part where the additional graphic is not separated from the original graphic by a predetermined distance is provided. Made it possible.

[Brief description of the drawings]

FIG. 1 is a flowchart showing processing of an example of an embodiment of a method for verifying photomask pattern data with an additional graphic according to the present invention;

FIG. 2A is a diagram showing a part of photomask pattern data with an additional figure (corresponding to 110 in FIG. 1);
FIG. 2B is a diagram of the composite data (corresponding to 150 in FIG. 1).
FIG. 3 is a diagram showing an area corresponding to FIG.

FIG. 3A is a diagram showing data obtained by removing a figure of design data from photomask pattern data with an additional figure, and FIG. 3B is a diagram showing data oversized the data; is there.

FIG. 4 is a diagram for explaining a graphic calculation process of pattern data;

FIG. 5 is a diagram showing a processing surface state of a wafer.

FIG. 6 is a flowchart of a pattern data creation method according to a conventional technique.

FIG. 7 is a diagram showing a state in each processing of a pattern data creating method according to a conventional technique.

[Explanation of symbols]

110 Photomask pattern data with additional graphic 120 Design data 120A Graphic 120a (of design data) Graphic position 121 Oversize data 130 Additional graphic data 130A Additional graphic 130a Graphic position 131 Oversize data 132 Oversize data 132A Overlap 140 All areas Data 150 Synthetic data 151 Blank part 160 Additional graphic missing area data 170 Overlapping part data 180 Error part data 191 Additional graphic missing area data creation processing (also referred to as additional graphic missing area extraction processing) 192 Overlapping part data creation processing (extraction of defective interval part) DP design data DT Additional graphic data (also simply referred to as additional graphic data) FPO Pattern data with additional graphic AD area data ad Additional graphic area dd Missing additional graphic (Also referred to as small additional figure) dp figure (also referred to as circuit pattern or figure pattern) dt additional figure (also referred to as additional pattern) dist Minimum interval

Continuation of the front page (72) Inventor Nobuto Toyama 1-1-1, Ichigaya-Kagacho, Shinjuku-ku, Tokyo Inside Dai Nippon Printing Co., Ltd. (72) Inventor Sakata Wakahiko 1-1-1, Ichigaga-cho, Shinjuku-ku, Tokyo No.1 Dai Nippon Printing Co., Ltd. F-term (reference) 2H095 BB01 BB02 BD01 5B046 AA08 BA04 DA05 GA01 JA02 5F064 DD08 DD13 DD24 HH10 HH15

Claims (3)

[Claims] 1. A predetermined distance from each figure in the design data is set to photomask pattern data with an additional figure in which a plurality of square figures for uniforming the figure density are provided in the design data. A method of verifying photomask pattern data with an additional figure, which verifies whether or not the rectangular figure is formed in a two-dimensional array at a predetermined pitch in each of the X direction and the Y direction in a region having no figure. (A) pattern data obtained by oversizing the design data by a predetermined value with respect to the design data obtained by removing the additional graphic from the photomask pattern data with the additional graphic, and the photomask pattern with the additional graphic Pattern data obtained by oversizing a rectangular figure by a predetermined value that connects the rectangular figures to the pattern data excluding the design data figure from the data. After performing a logical OR graphic process on the data and obtaining composite data, a logical NOT graphic process is performed on the obtained composite data and all area data representing the entire area of the design data, and a photomask pattern with an additional graphic is obtained. An additional figure lacking area data creating process for creating pattern data representing only an area where a rectangular figure of data is missing;
(B) pattern data obtained by oversizing a rectangular figure by a predetermined value connecting the rectangular figures to the pattern data obtained by removing the design data figure from the photomask pattern data with the additional figure; And logic A
A method of verifying photomask pattern data with an additional figure, comprising performing ND figure processing and performing overlapping part data creation processing for creating pattern data representing only the overlapping part of both pattern data. 2. The photomask pattern data with an additional figure with a rectangular additional figure according to claim 1,
(A) An additional graphic arrangement area representing an area in which an additional graphic is to be arranged by subtracting pattern data in which a graphic of the design data is oversized by a predetermined size from the entire area data representing the entire area of the design data by logical NOT graphic processing. (B) additional graphic arrangement area data AD, which creates data AD, and (b) a rectangular graphic in the X direction and Y direction over the entire area corresponding to the entire area of the design data. A logical AND graphic process is performed on the additional graphic pattern data DT two-dimensionally arranged at a predetermined pitch. A logical AND graphic process and (c) an undersize process are sequentially performed on the pattern data obtained by the logical AND graphic process. And oversize processing to obtain the logic A
(D) combining the design data with the pattern data obtained by the deletion processing to delete the missing additional graphic in a state where the rectangular figure is missing from the pattern data obtained by the ND graphic processing; Creates photomask pattern data with a rectangular additional figure, and performs synthesis processing. The overlapping part extraction processing is a predetermined value oversize of the pattern data obtained by the deletion processing. A logical AND graphic process is performed on the pattern data and the design data obtained as a result, and pattern data representing only an overlapping portion of the two pattern data is extracted. Verification method. 3. The method according to claim 2, wherein the pattern data representing only the area where the additional graphic is missing, obtained by the additional graphic missing area data generating processing, and the overlapping part obtained by the overlapping part data generating processing are included. A method for verifying photomask pattern data with an additional graphic, comprising combining the pattern data with the pattern data to represent the error portion.