CN104166304B - Method for correcting auxiliary pattern - Google Patents

Abstract

The invention provides a method for correcting an auxiliary pattern, which comprises the following steps. First, a computer system receives a first layout pattern and divides the first layout pattern into a plurality of first areas. Then, a plurality of auxiliary patterns are added in the first layout pattern to form a second layout pattern, at least one auxiliary pattern adjacent to any side line of any first area is defined as a selected pattern, and then the second layout pattern is divided into a plurality of second areas. Finally, a detection step is carried out on the second area with the selected pattern, and the second layout pattern is corrected to form a corrected second layout pattern.

Description

How to Correct Auxiliary Patterns

technical field

The present invention relates to a method for correcting an auxiliary pattern, especially a method for correcting an auxiliary pattern before correcting an original layout pattern by an optical proximity correction (OPC) method.

Background technique

As electronic products and their peripheral products are developing in the direction of being light, thin and short, in the semiconductor manufacturing process, component miniaturization and integration are an inevitable trend, and are also an important topic for active development in all walks of life. Among them, lithography is the key to determine the performance of components. key technologies.

The current semiconductor process is to first form the layout pattern of integrated circuits on a photomask, and then transfer the pattern on the photomask to the photoresist layer on the semiconductor chip in a certain proportion through exposure and development steps. , and further cooperate with the relevant etching process to gradually form the components on the semiconductor chip. With the improvement of the integration degree of integrated circuits, the size of components is reduced, and the distance between components is also reduced. However, due to the influence of factors such as optical proximity effect (OPE), the distance of the above-mentioned components has already faced its limit in the exposure process. For example, in order to obtain micro-sized components, the pitch of the light-transmitting regions of the mask will be reduced in accordance with the size of the components, but if the pitch between the light-transmitting regions is reduced to a certain range (the exposure wavelength is 1/2 or below), the light passing through the mask will undergo diffraction, interference and other phenomena, which will affect the resolution of the transferred pattern, resulting in a deviation of the pattern on the photoresist, such as right-angled rounding (right-angled). Corner rounded, line end shortened, and line width increase/decrease are all common photoresist pattern defects caused by optical proximity effect.

In order to solve the above-mentioned problems, the known technology reduces the photoresist by forming an assist pattern, such as a dummy pattern or a scattering bar, between the layout patterns of the integrated circuits on the photomask. Occurrence of pattern defects. How to form a suitable auxiliary pattern to further form a desired layout pattern in the target layer is a subject to be improved by those skilled in the art.

SUMMARY OF THE INVENTION

One of the objectives of the present invention is to provide a method for correcting an auxiliary pattern, so as to improve the accuracy of the mask pattern, thereby forming a desired layout pattern.

A preferred embodiment of the present invention provides a method for correcting an auxiliary pattern, which includes the following steps. First, a first layout pattern is received by a computer system, and the first layout pattern is divided into a plurality of first regions. Next, a plurality of auxiliary patterns are added to the first layout pattern to form a second layout pattern, and at least one auxiliary pattern on any side of any adjacent first region is defined as a selection pattern, and then the second layout pattern is defined The pattern is divided into a plurality of second regions. Finally, a detection step is performed on the second area having the selected pattern, and the second layout pattern is corrected to form a corrected second layout pattern.

The invention is characterized in that, before performing the optical proximity correction operation on the layout pattern, the layout pattern is first divided into two operations, so as to improve the correctness of the added auxiliary pattern. In more detail, firstly, the layout pattern is divided for the first time to form a plurality of first regions, and the auxiliary pattern on the boundary of the adjacent first region is selected as the selection pattern; then, the second division is carried out, for example: expanding The first area containing the selected pattern or the first area is translated to form the second area, so that the boundary of the second area does not overlap the selected pattern, and the pattern contained in the second area is different from the pattern contained in the first area, to further confirm The relative relationship between the selected pattern and the adjacent pattern (especially the auxiliary pattern not originally included in the first area). Accordingly, the setting of inappropriate auxiliary patterns can be avoided, and the correctness of the mask pattern can be improved to form a desired layout pattern.

Description of drawings

FIG. 1 is a flowchart illustrating a method for correcting an auxiliary pattern according to a preferred embodiment of the present invention.

2 to 9 are schematic diagrams illustrating a method for correcting an auxiliary pattern according to a preferred embodiment of the present invention.

FIG. 10 is a flowchart illustrating a method for correcting an auxiliary pattern according to a preferred embodiment of the present invention.

[label description]

10, 12, 14, 16, 18, 20, 22, 24, steps

26, 28, 30, 301, 302, 303, 304

100 First layout pattern

102, 104 First area

106 Second layout pattern

108, 110 Corrected second layout pattern

112, 114 Corrected first layout pattern

202, 204, 202', 204' Second area

D1 Horizontal I spacing

IP endpoint

L1, L2, L3, L4 Sidelines

P1 pattern P1’ auxiliary pattern

P1” corrected auxiliary pattern

P11, S1’ Corrected sub-auxiliary pattern

P2 Discrimination pattern P2’ Corrected discrimination pattern

P3, P4 Corrected auxiliary patterns

S1, S2, S3 select pattern

W width

Detailed ways

In order to enable those of ordinary skill in the technical field to which the present invention pertains to further understand the present invention, preferred embodiments of the present invention are specifically enumerated below, and in conjunction with the accompanying drawings, the composition of the present invention and the desired effect will be described in detail. .

Please refer to Figure 1. FIG. 1 is a flowchart illustrating a method for correcting an auxiliary pattern according to a preferred embodiment of the present invention. As shown in FIG. 1 , first, step 10 is performed to receive a first layout pattern from a computer system. The first layout pattern refers to a material layer (not shown) to be subsequently transferred to a mask or a semiconductor chip, such as : The ideal pattern of the photoresist layer, which includes a plurality of printable features, and these printable patterns can include any feature patterns used to form integrated circuits (IC), such as doped Miscellaneous region pattern, element pattern, circuit layout pattern, etc. As the complexity and integration of the feature patterns of the integrated circuit increase, in order to reduce the computing load of the computer system and the computing time of the subsequent steps, step 12 may be performed, and a computer system first divides the first layout pattern into a plurality of The first area, for example: when the first layout pattern is a rectangular pattern, the first layout pattern is divided into a plurality of rectangular first areas of the same size, and then the plurality of first areas are respectively input to other computer systems to Multiple computer systems perform subsequent processing steps at the same time, saving computing processing time. In one embodiment, when the first layout pattern is a square with a side length of 100 micrometers (micrometer, μm), the first layout pattern is divided into 100 first regions arranged in a matrix, and each first region has a side length. 10 micron square.

Since the distance between the transferable pattern in the first layout pattern and another adjacent transferable pattern is not necessarily the same, if the first layout pattern is directly formed on the photomask, and the photomask is used for subsequent In the lithography process, the amount of light transmission on both sides of part of the transferable pattern may be different, that is, part of the pattern formed on the material layer will be offset or deformed. Therefore, in order to improve the first For the correctness of transferring a layout pattern to the material layer, step 14 is performed to add a plurality of auxiliary patterns to the first layout pattern to form a second layout pattern. The auxiliary pattern is a non-printable feature. More specifically, when a photosensitive material layer on the wafer is subjected to a micro-pattern using the mask having the first layout pattern and the auxiliary patterns During the filming process, only the pattern corresponding to the first layout pattern will be formed on the material layer, and the pattern corresponding to the auxiliary pattern will not be formed on the material layer. In one embodiment, the first layout pattern includes a plurality of rectangular patterns, and the shape of the added auxiliary pattern is similar to that of the first layout pattern, so as to uniformize the pattern density of the second layout pattern, that is, when When the light source passes through the mask with the second layout pattern, the amount of light transmission on both sides of each transferable pattern of the second layout pattern will be relatively consistent, so that the desired amount of light can be formed on the material layer during the subsequent lithography process. layout pattern. The size, shape, quantity and arrangement of the auxiliary pattern can be adjusted according to the process requirements. In addition, the size range and arrangement of the auxiliary pattern must conform to the process rule check (PRC) rules of the auxiliary pattern. For example: critical Line width (critical dimension) and critical spacing (critical space) constraints. In one embodiment, the width of each auxiliary pattern is smaller than a specific value, that is, the maximum size of the pattern that will not be exposed on the mask in this lithography process, and is larger than the exposure limit of the mask making machine, which can be determined by The minimum size of the pattern formed by the mask fabrication machine, in more detail, taking a semiconductor process with a feature size of 20 nanometers (nm) as an example, the maximum size of the pattern that will not be exposed in the mask is substantially about 32 nanometers, and the exposure limit of the mask fabrication machine is substantially about 13 nanometers, so the width of the auxiliary pattern is substantially between 13 nanometers and 32 nanometers, but not limited thereto.

In addition, in order to save the computing time of the computer system, the auxiliary pattern is preferably added to the first layout pattern of each first area by a plurality of computer systems at the same time, that is, the present invention uses a plurality of computer systems to simultaneously The first layout patterns in the different first regions are respectively corrected, and the first layout patterns in the different first regions are independently corrected to add required auxiliary patterns. Then, the first layout patterns and the auxiliary patterns of the first regions are recombined to form a second layout pattern. It is worth noting that, because each first area only contains a part of the first layout pattern, which is different from the complete original first layout pattern, that is, the computer system provides the auxiliary pattern according to the partial first layout pattern. The correction effect may be different from the correction effect provided by the auxiliary pattern added by the computer system according to the complete first layout pattern. Therefore, the present invention will further use the auxiliary patterns in the two adjacent first areas to refer to each other to confirm each first area. The correctness of the auxiliary pattern. In order to shorten the time required for confirming the correctness of the auxiliary pattern, the present invention selects the auxiliary pattern adjacent to the edge of the first area to perform the subsequent first detection step. The at least one auxiliary pattern is a selection pattern. In other embodiments, at least one auxiliary pattern whose distance from any edge of any first region is less than a predetermined value can also be defined as a selection pattern.

Next, step 16 is performed, and the second layout pattern is re-divided into a plurality of second regions. The method of dividing the second layout pattern into a plurality of second regions may include:

a. Resize the first region to form the second region; or

b. Move each original first region in either direction to form a second region; or

c. With the selected pattern as a reference point, select a specific range.

Further, the edge of the re-divided second area is preferably not in contact with any auxiliary pattern, and the pattern contained in the single second area, that is, the first layout pattern and the auxiliary pattern contained in the second area are different from the corresponding single first layout pattern. The pattern included in the region is the first layout pattern and the auxiliary pattern included in the corresponding first region. It is worth noting that changing the size of the first area to form the second area also includes expanding the first area or reducing the first area, and the number of the second area after division may not be equal to the number of the first area. The rear second regions may partially overlap the corresponding first regions. For example, the method for enlarging the first area includes moving at least one edge of each first area in any direction, especially the edge of the first area that is in contact with or adjacent to the auxiliary pattern, and translates it as an edge of the second area , and the distance between the edge of each second area (re-segmented) and the corresponding edge of the first area (original segmentation) (that is, the moving distance of the edge of the first area) is substantially greater than or equal to a specific value, and Make the area of the second area larger than the area of the first area; or, directly expand the first area in situ, that is, move each edge of each first area to form a corresponding second area. The number of the divided second areas is equal to the number of the first areas, and the re-divided second areas will partially overlap each other, for example: each first area is a square with a side length of 10 microns, and each second area is a side A square with a length of 13 microns. Taking the selected pattern as a reference point and selecting a specific area to divide the second layout pattern, the specific area includes a circular area with an endpoint of the selected pattern as a center and a specific value as a radius. Wherein, the setting of the specific value may correspond to the size of the auxiliary pattern, for example: the specific value is a maximum side length of a pattern substantially larger than the auxiliary patterns, or corresponds to the critical line width of the auxiliary pattern, for example: the specific value It is the maximum size of a pattern in the mask that will not be exposed for a lithography process using a mask.

After that, go to step 18 to perform a first detection step on the second layout pattern, especially select a second area with the selected pattern to perform a first detection step. It is worth noting that, in a preferred embodiment, multiple computer systems are used to simultaneously detect the auxiliary patterns (with selected patterns) of each second region, that is, the present invention utilizes multiple computer systems to simultaneously The auxiliary patterns (which have selected patterns) in each second area are independently tested to confirm whether the auxiliary patterns, especially whether the selected patterns conform to the process rules of the auxiliary patterns, are detected, such as: the critical line width and the critical line width of the auxiliary patterns. Spacing restrictions. In addition, in another preferred embodiment, the second area with the selected pattern can also be directly screened for independent detection. For example, the second layout pattern is divided into 100 second areas, but only 50 second areas have If the pattern is selected, it is only necessary to use multiple computer systems to independently test the auxiliary patterns in the 50 second regions at the same time to confirm whether the auxiliary patterns conform to the rules of the process rule detection of the auxiliary patterns; or, directly The selected patterns in the 50 second regions are independently detected. In addition, in another preferred embodiment, the method for performing the first detection step may also include directly performing the first detection step on a single selected pattern to confirm whether the selected pattern conforms to the process rule detection rule of the auxiliary pattern, for example: the auxiliary pattern The critical line width and critical spacing limit, or first combine the selected pattern and any auxiliary pattern adjacent to the selected pattern to form a discriminating pattern, and then confirm whether the discriminating pattern conforms to the process rule detection of the auxiliary pattern.

When any of the auxiliary patterns, eg, the selection pattern or the discrimination pattern, fails the first detection step, step 20 is performed to correct the second layout pattern to form a corrected second layout pattern. The method of revising the second layout pattern includes revising the selection pattern, for example: increasing the side length of the selection pattern, so that the side length of the revised selection pattern is greater than the minimum length limit of the side length of the auxiliary pattern, so that the revised selection pattern can reach the set The function of the auxiliary pattern is, for example, to homogenize the light transmittance of the subsequently formed mask; or to reduce the side length of the selected pattern so that the side length of the corrected selected pattern is smaller than the maximum size of the pattern that will not be exposed in the mask, That is to say, the modified selection pattern will not be formed on the target material layer by a subsequently formed photomask. Accordingly, the corrected second layout pattern includes the first layout pattern, part of the original auxiliary pattern and the corrected selection pattern.

Similarly, the auxiliary patterns corresponding to the discriminant patterns can also be respectively corrected in the above-mentioned manner to form a plurality of revised sub-auxiliary patterns, and then the revised sub-auxiliary patterns can be combined to form a revised discriminant pattern, for example: When the side length of the discriminant pattern is larger than the maximum size of the pattern that will not be exposed in the mask, the side length of the selected pattern and the side length of the auxiliary pattern of the adjacent selected pattern in the discriminant pattern are respectively reduced to form a plurality of corrected patterns. Sub-assistant pattern (including the corrected selection pattern and corrected auxiliary pattern), and then, the corrected sub-assistant pattern is combined into the corrected discrimination pattern, so that the corrected discrimination pattern will not pass through the mask formed subsequently is formed on the target material layer. In other embodiments, the modification of the discrimination pattern may only modify any one of the selected pattern in the discrimination pattern and the auxiliary pattern adjacent to the selected pattern in the discrimination pattern. Accordingly, the corrected second layout pattern includes the first layout pattern, part of the original auxiliary pattern and the corrected discrimination pattern.

Next, go to step 22, after correcting part of the auxiliary pattern (especially the selection pattern), perform at least one optical proximity correction (OPC) on the corrected second layout pattern to form a corrected first layout pattern and several corrected auxiliary patterns. Optical Proximity Correction (OPC) may include first collecting the width, sparseness and sparseness of each geometric pattern (ie, the first layout pattern, the original auxiliary pattern, and the corrected selection pattern/corrected discrimination pattern) in the corrected second layout pattern. The density and relative position are then compared with the correction benchmarks in the database, and the correction values of each geometric pattern are calculated to correct the line width, straight line ends and corners of each line segment in each geometric pattern. In general, the correction method includes adjusting the line width of the line segment, or adding auxiliary blocks such as serif or hammerhead patterns at the ends or corners of the line.

Then, go to step 24, that is, a second detection step is performed to check whether the corrected first layout pattern and the corrected auxiliary pattern that have completed the first detection step and the optical proximity correction operation respectively conform to the process rules of the layout pattern. The rule and the process rule detection rule of the auxiliary pattern are used to further confirm the correctness of the corrected first layout pattern and the corrected auxiliary pattern. For example, a process rule is input through the simulation mode of the computer system, and the process rule detection is used to detect the straight line ends and corners of each line segment in the modified first layout pattern, so as to determine whether these geometric patterns conform to the designed integration. The limits of the critical dimension and critical space of the feature pattern of the circuit or other rules of the process design. When the corrected first layout pattern and the corrected auxiliary pattern completely conform to the rules detected by the respective process rules, as shown in step 26, the computer system can output the corrected first layout pattern and the corrected auxiliary pattern to a photomask; however, if some or all of the corrected first layout pattern and/or the corrected auxiliary pattern do not meet the rules of the process rule inspection, the corrected first layout pattern and/or the corrected first layout pattern and/or the corrected The auxiliary pattern of , again utilizes the computer system to perform partial or complete re-correction with the aforementioned steps. Finally, as shown in step 28, a lithography process is performed on a material layer using the mask to form a first layout pattern on a material layer, and any auxiliary patterns and modified auxiliary patterns are not formed on the material layer . The material layer includes a photoresist layer disposed on a wafer.

In addition, when the first detection step shown in step 18 is completed and the second layout pattern passes the detection step, an optical proximity correction (OPC) step similar to that shown in step 22 can be performed, that is, as shown in step 30 , directly performing at least one optical proximity correction (OPC) on the second layout pattern to form a corrected first layout pattern and a plurality of corrected auxiliary patterns. Then, go to step 24 in the same way: check whether the corrected first layout pattern and the corrected auxiliary pattern respectively conform to the rules of the process rule detection of the layout pattern and the process rule detection of the auxiliary pattern after completing the optical proximity correction (OPC). Rule, if yes, then go to step 26: output the modified first layout pattern and the modified auxiliary pattern to a mask by the computer system, if not, send the modified first layout pattern and/or the modified auxiliary pattern The pattern is then partially or fully re-corrected using the computer system in the aforementioned steps. Finally, as shown in step 28, a lithography process is performed on the material layer using the mask to form the first layout pattern on a material layer, and no auxiliary pattern is formed on the material layer.

In order to describe the above steps in more detail, please refer to FIGS. 2 to 9 . FIGS. 2 to 9 are schematic diagrams illustrating a method for correcting an auxiliary pattern according to a preferred embodiment of the present invention, and please refer to the preferred embodiment of FIG. 1 . each process step.

Step 10: Receive a first layout pattern by a computer system.

Step 12: Divide the first layout pattern into a plurality of first regions.

As shown in FIG. 2, first, a first layout pattern 100 is received by a storage medium of a computer system (not shown), and the first layout pattern 100 is divided into a plurality of first regions 102/104, wherein the first The layout pattern 100 includes a plurality of transferable patterns P1, ie, feature patterns used to form an integrated circuit (IC). In this embodiment, the first layout pattern 100 is divided into two first regions 102/104 of the same area, but not limited to this, the first layout pattern 100 may be divided into more first regions to The processing time of more subsequent steps is shortened, and each first region can include transferable patterns of different shapes, numbers or arrangements.

Step 14: Add a plurality of auxiliary patterns to form a second layout pattern, and define at least one auxiliary pattern on any side of any adjacent first region as a selection pattern.

Next, as shown in FIG. 3 , in order to prevent pattern defects from being formed on the material layer due to the optical proximity effect, a plurality of auxiliary patterns P1 ′ are respectively added to different first regions 102 / 104 by different computer systems, and then combined The first regions 102/104 already have the auxiliary patterns to form a second layout pattern 106. At this time, both the pattern P1 and the auxiliary pattern P1' of the second layout pattern 106 have not been corrected by optical proximity correction (OPC). The size, shape, quantity and arrangement of the auxiliary patterns P1' can be adjusted according to the process requirements. In this embodiment, the size of the auxiliary pattern P1' is substantially larger than the size of the original pattern P1 of the first layout pattern 100. In addition, the auxiliary pattern P1 ′ close to the edge of the first area 102 / 104 can be preselected for subsequent detection steps, and the detection steps of other auxiliary patterns P1 ′ can be omitted to reduce the fabrication time of the mask. The detection step refers to The auxiliary patterns P1 ′ in the two adjacent first regions 102 / 104 confirm the correctness of the auxiliary patterns P1 ′ in each of the first regions 102 / 104 . In this embodiment, the auxiliary pattern P1' contacting the side line L1 of the first region 102 is defined as a selection pattern S1. In other embodiments, the auxiliary pattern P1' whose distance between the second layout pattern 106 and the edge L2 of the first region 104 is less than a predetermined value can also be selected as the selection pattern S2. In addition, when two adjacent first regions 102/104 in the second layout pattern 106 both have an auxiliary pattern P1' on both sides of the same edge L1 as the selection pattern, only any one of them is selected, for example: the first The selection pattern S1 of the area 102 is used as the target pattern to carry out the subsequent first detection step, and another such as: the selection pattern S3 of the first area 104 is used as the target pattern to carry out the subsequent detection steps, so as to avoid repeated calculation and increase the computer system load. The following embodiments will be described by defining the implementation aspect of selecting the pattern S1 as the target pattern.

Step 16: Divide the second layout pattern into a plurality of second regions.

Next, the second layout pattern 106 is divided into a plurality of second areas 202/204, so that the edge of the second area 202 does not directly contact the selection pattern S1, and the first layout pattern 100 (also That is, the pattern P1) and the auxiliary pattern P1' are different from the first layout pattern 100 and the auxiliary pattern P1' contained in the corresponding first regions 102/104. The method of dividing the second layout pattern 106 into a plurality of second regions 202/204 includes moving each first region in either direction, eg, expanding the first region 102 with the selection pattern S1 to form the second region 202, as shown in FIG. 4 . For example, moving the edge L1 of the first region 102 along the horizontal direction D1, that is, moving the first region 102 contacted by the auxiliary pattern P1' (selected pattern S1) The edge L1 of the second region 202 is used as the edge L3 of the second region 202, and the distance I between the edge L3 of the second region 202 and the corresponding edge L1 of the first region 102 is substantially greater than or equal to a specific value, in order to effectively confirm the auxiliary pattern For the correctness of P1', the specific value can be greater than the maximum side length of a pattern of the auxiliary pattern P1' in the second layout pattern 106, preferably the critical line width of the auxiliary pattern P1', for example, using a photomask for lithography During the manufacturing process, the maximum size of a pattern that will not be exposed in the mask is preferably the sum of a critical line width and a critical spacing of the auxiliary pattern P1'. In this embodiment, only the right edge L1/L2 of each first area 102/104 is moved along the horizontal direction D1, and other original edges of each first area 102/104 are retained, so as to separate the second layout pattern 106 from Different from the division by unit interval of the first layout pattern 100 , in more detail, the left edge of the second area 202 corresponds to the original left edge of the first area 102 , and the right edge corresponds to the horizontally shifted The right side line L1 of the first region 102 is the side line L3. Similarly, the left sideline of the second area 204 is the original left sideline of the corresponding first area 104 (ie, the right sideline L1 of the first area 102 ), and the right sideline is the corresponding horizontally moved sideline The right edge L2 of the first region 104 is the edge L4. At this time, the distances between the sidelines L3/L4 of the second areas 202/204 and the sidelines L1/L2 of the corresponding first areas 102/104 are equal, and the total number of the second areas is substantially equal to that of the first areas. However, the area occupied by each second region 202/204 will be substantially larger than that of the corresponding first region 102/104. For example, the first region is a square with a side length of 10 microns, and the second region It is a rectangle with a side length of 13 microns and a side length of 10 microns.

The method of dividing the second layout pattern 106 into a plurality of second regions is not limited to the above, and in other embodiments, only the right edge L1 of the first region 102 may be moved along the horizontal direction D1, that is, only the selected pattern may be moved. The edge L1 contacted by S1 is used as the right edge L3 of a second area, and the original right edge of the first area 104 is retained. For example, the edge L2 of the first area 104 is not moved, so that the The right side line will overlap the side line L2 of the first area 104. At this time, the occupied area of part of the second area (including the selection pattern S1) will be substantially larger than the area occupied by the corresponding first area, while part of the second area The occupied area of the region (excluding the selection pattern S1 ) will be substantially smaller than the occupied area of the corresponding first region.

In addition, in another embodiment, the selection pattern may be directly selected. As shown in FIG. 5 , taking the selected pattern S1 as a reference point, and taking an endpoint IP of the selected pattern S1 as the center of the circle, a circular area with a radius of the above-mentioned specific value is selected as a second area 202 ′, and the second layout is The other ones of the patterns 106 are defined as another second region 204'.

Step 18: Select the second area with the selected pattern to perform a first detection step.

Next, the auxiliary patterns in each of the second regions 202 / 204 are simultaneously detected by two computer systems to confirm whether the auxiliary patterns, especially the selected patterns S1 , S2 , and S3 conform to the process rule detection rules of the auxiliary patterns. For example, the first detection step is performed on the second region 202 with the selection patterns S1, S3. The method for performing the first detection step includes directly performing the first detection step on the selected pattern S1 to confirm whether the selected pattern S1 conforms to the process rule detection rule of the auxiliary pattern P1', for example: the difference between the critical line width and the critical spacing of the auxiliary pattern P1'. limitations, and limitations on the spacing between the auxiliary pattern P1' and the transferability pattern P1. Or first combine the selected pattern S1 and the auxiliary pattern P1' adjacent to the selected pattern S1, for example: select the pattern S3 to form a discrimination pattern P2, and then confirm whether the discrimination pattern P2 conforms to the process rule detection of the auxiliary pattern P1'.

Step 20: Modify the second layout pattern to form a corrected second layout pattern.

When the selection pattern S1 or the discrimination pattern P2 cannot pass the first detection step, the second layout pattern 106 needs to be corrected, that is, the selection pattern S1 or the discrimination pattern P2 is corrected. The method for correcting the selection pattern S1 is described as follows. Since the selection pattern S1 contacts the adjacent auxiliary pattern P1' (the selection pattern S3), which does not conform to the detection of the auxiliary pattern process rules, the size of the selection pattern S1 can be reduced, for example, a width of the selection pattern S1 can be reduced, or the selection pattern can be removed. Pattern S1, so that the corrected auxiliary pattern P1" is for example: the combined pattern of the corrected selection pattern S1 and the adjacent auxiliary pattern P1' (selection pattern S3), or the remaining adjacent auxiliary pattern P1' (selection pattern S3) , which can conform to the rules of the auxiliary pattern process rule detection to form a modified second layout pattern 108 , as shown in FIG. 6 .

In addition, the method of correcting the discrimination pattern P2 will be described below. After combining the selection pattern S1 and the auxiliary pattern P1' (the selection pattern S3) near the boundary of the first area 102/104, that is, the edge line L1, into the discrimination pattern P2, a width W of the discrimination pattern P2 is substantially larger than the auxiliary pattern P1' When the critical line width is , the width W of the discrimination pattern P2 can be reduced. For example, the width of the selected pattern S1 can be reduced to form a modified sub-auxiliary pattern S1 ′ and/or the width of the auxiliary pattern P1 ′ constituting the discrimination pattern P2 can be reduced to form a modified auxiliary pattern S1 ′. Sub auxiliary pattern P11, then, these modified sub auxiliary patterns S1'/P11 are combined to form a modified discrimination pattern P2', so that the side length of the corrected discrimination pattern P2' is substantially smaller than that in the photomask. The maximum size of the exposed pattern complies with the rule of the auxiliary pattern process rule detection to form a modified second layout pattern 110 , as shown in FIG. 7 . At this time, the size of the corrected discrimination pattern P2' and the size of each auxiliary pattern P1' in the corrected second layout pattern 110 are still substantially larger than the size of any pattern P1 of the first layout pattern 100.

Step 22: After correcting the selected pattern, perform optical proximity correction (OPC) on the corrected second layout pattern to form a corrected first layout pattern and a plurality of corrected auxiliary patterns.

After selecting the pattern S1 in the correction part and improving the correctness of the auxiliary pattern P1', as shown in FIG. 8 and FIG. At least one optical proximity correction (OPC) correction is performed at the end and the corner to form a corrected first layout pattern 112/114 and a plurality of corrected auxiliary patterns P3/P4. At this time, the size of any one of the corrected auxiliary patterns P3/P4 will be substantially smaller than the size of any one of the corrected first layout patterns 112/114.

Step 24: Perform a second detection step to check whether the corrected first layout pattern and the corrected auxiliary pattern that have completed the first detection step and the optical proximity correction operation respectively conform to the rules of the process rule detection of the layout pattern and the auxiliary pattern. Routing rule detection rules.

Step 26: The computer system outputs the corrected first layout pattern and the corrected auxiliary pattern to a mask.

Step 28: Use a photomask to perform a lithography process on the material layer to form a first layout pattern to a material layer.

Finally, it is confirmed again whether the corrected first layout patterns 112 / 114 and the plurality of corrected auxiliary patterns P3 / P4 conform to the rules of the process rule detection of the layout patterns and the rules of the process rule detection of the auxiliary patterns. After confirming that they are in compliance, the subsequent steps (step 26 and step 28) can be performed to form the first layout pattern 100 to a material layer, and the auxiliary patterns P1' are not formed to the material layer.

In brief, please refer to Figure 10. FIG. 10 is a flowchart illustrating a method for correcting an auxiliary pattern according to a preferred embodiment of the present invention. As shown in step 301, a first layout pattern is first received by a computer system, and the first layout pattern is divided into a plurality of first regions. As shown in step 302, the present invention firstly utilizes multiple computer systems to perform independent correction processing on the layout patterns in each first area at the same time, so as to add required auxiliary patterns, and then combine the multiple computer systems that already have auxiliary patterns. a first region to form a second layout pattern. Next, as shown in step 303, the second layout pattern including the temporary auxiliary pattern and the first layout pattern is re-divided into a plurality of second regions, and then, as shown in step 304, multiple computer systems are used to simultaneously The auxiliary patterns (including the selected patterns) in each second area are independently tested to confirm whether the auxiliary patterns, especially the selected patterns, conform to the rules of the process rule detection of the auxiliary patterns, and are corrected to obtain the optical The final auxiliary pattern before proximity correction. In addition, at least one optical proximity correction (OPC) may be additionally performed on the corrected second layout pattern (ie, the final auxiliary pattern before the optical proximity correction and the first layout pattern). In other words, the present invention will perform secondary pattern division. The first pattern division is used to add the required auxiliary patterns in each first area, and the second pattern division is used to confirm each second area. Whether the auxiliary pattern, especially the selected pattern, conforms to the rules of the process rule detection of the auxiliary pattern.

To sum up, the present invention is characterized in that, before performing the optical proximity correction operation on the layout pattern, the layout pattern is first divided into two operations to improve the accuracy of the added auxiliary pattern. In more detail, firstly, the layout pattern is divided for the first time to form a plurality of first regions, and the auxiliary pattern on the boundary of the adjacent first region is selected as the selection pattern; then, the second division is carried out, for example: expanding The first area containing the selected pattern or the first area is translated to form the second area, so that the boundary of the second area does not overlap the selected pattern, and the pattern contained in the second area is different from the pattern contained in the first area, to further confirm The relative relationship between the selected pattern and the adjacent pattern (especially the auxiliary pattern not originally included in the first area). Accordingly, the setting of inappropriate auxiliary patterns can be avoided, and the correctness of the mask pattern can be improved to form a desired layout pattern.

Claims (19)

1. A method of correcting an auxiliary pattern, comprising: receiving a first layout pattern by a computer system; dividing the first layout pattern into a plurality of first regions; A plurality of auxiliary patterns are added to the first layout pattern to form a second layout pattern, and at least one of the auxiliary patterns that is in contact with any edge of any of the first regions or whose distance is less than a predetermined value is defined as a selection pattern; The second layout pattern is divided into a plurality of second areas, so that the edges of the plurality of second areas do not contact any auxiliary pattern, and the first layout pattern and the auxiliary pattern contained in the second area are different from the corresponding first layout patterns. a first layout pattern and an auxiliary pattern included in a region; performing a detection step on the second area having the selected pattern; and The second layout pattern is modified to form a modified second layout pattern. 2. The method for revising auxiliary patterns according to claim 1, further comprising: At least one optical proximity correction is performed on the corrected second layout pattern to form a corrected first layout pattern and a plurality of corrected auxiliary patterns. 3. The method of claim 2, wherein a size of any one of the plurality of modified auxiliary patterns is substantially smaller than a size of any one of the modified first layout patterns. 4. The method for revising auxiliary patterns according to claim 2, further comprising: outputting the modified first layout pattern and the modified auxiliary pattern to a reticle by the computer system; and A lithography process is performed on a material layer using the photomask to form the modified first layout pattern on the material layer. 5. The method of claim 4, wherein the plurality of modified auxiliary patterns are not formed on the material layer. 6. The method of claim 1, wherein the method of dividing the second layout pattern into a plurality of second regions comprises changing the size of at least one of the first regions to form the second regions. 7 . The method of claim 6 , wherein the distance between an edge of each of the second regions and the edge of the corresponding first region is substantially greater than or equal to a specific value, wherein the specific The value corresponds to the size of the auxiliary pattern or to the critical line width of the auxiliary pattern. 8. The method of claim 7, wherein the specific value is substantially greater than a maximum side length of any one of the auxiliary patterns among the plurality of auxiliary patterns. 9 . The method of claim 7 , wherein the specific value is a maximum size of a pattern that will not be exposed when a photomask is used for a lithography process. 10 . 10 . The method of claim 1 , wherein each of the second regions partially overlaps at least one corresponding first region. 11 . 11. The method of claim 1, wherein the number of the plurality of second regions is substantially not equal to the number of the plurality of first regions. 12. The method of claim 1, wherein the method of dividing the second layout pattern into a plurality of second regions comprises moving each of the first regions in any direction. 13. The method of claim 12, wherein an area of each of the second regions is substantially equal to an area of each of the corresponding first regions. 14. The method of claim 1, wherein the method of dividing the second layout pattern into a plurality of second regions comprises using the selected pattern as a reference point, and selecting a specific range, wherein the specific range It includes a circular area with an end point of the selected pattern as the center and a specific value of the radius, the specific value corresponding to the size of the auxiliary pattern or corresponding to the critical line width of the auxiliary pattern. 15. The method of claim 14, wherein the specific value is substantially greater than a maximum side length of any one of the auxiliary patterns in the auxiliary patterns. 16 . The method of claim 1 , wherein the detecting step comprises confirming whether the selected pattern complies with a rule of process rule detection of an auxiliary pattern. 17 . 17. The method of claim 1, wherein the detecting step comprises: combining the selected pattern and any of the auxiliary patterns adjacent to the selected pattern to form a discrimination pattern; and It is confirmed whether the discriminating pattern complies with the rules of the process rule detection of an auxiliary pattern. 18. The method for revising an auxiliary pattern according to claim 17, wherein the method for revising the second layout pattern comprises: respectively correcting the plurality of auxiliary patterns corresponding to the discriminant patterns to form a plurality of corrected sub-auxiliary patterns; and The plurality of modified sub-auxiliary patterns are combined to form a modified discrimination pattern. 19. The method of claim 18, wherein in the modified second layout pattern, the size of the modified discrimination pattern and the size of each of the auxiliary patterns are substantially larger than the first The dimensions of either pattern of the layout pattern.

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