TW201443555A - Method of correcting assist features - Google Patents

Abstract

A method of correcting assist features includes the following steps. At first, a first layout pattern is received by a computer system, and the first layout pattern is split into a plurality of first regions. Subsequently, a plurality of assist features are added into the first layout pattern to form a second layout pattern, wherein at least one of the assist features neighboring any one of the edges of the first regions is defined as a selected pattern. Then, the second layout pattern is split into a plurality of second regions. Afterwards, a check step is performed on the second region including the selected pattern, and the second layout pattern is corrected to form a corrected second layout pattern.

Description

Method of correcting auxiliary patterns

The present invention relates to a method of correcting an auxiliary pattern, and more particularly to a method of correcting an auxiliary pattern before correcting an original layout pattern by an optical proximity correction (OPC) method.

As electronic products and their peripheral products are developing in a light, thin and short direction, in the semiconductor manufacturing process, component shrinkage and accumulation are inevitable trends, and they are also important topics for active development. Among them, lithography determines component performance. The key technology.

The current semiconductor process firstly forms a layout pattern of integrated circuits on a photomask, and then transfers the pattern on the photomask to a photoresist layer on the semiconductor wafer by a ratio of exposure and development steps. And further, in conjunction with the associated etching process, the components are gradually formed on the semiconductor wafer. As the integration of the integrated circuit increases, the component size shrinks and the distance between the component and the component decreases. However, due to factors such as optical proximity effect (OPE), the distance of the above components has reached its limit in the exposure process. For example, in order to obtain a small-sized component, the pitch of the light-transmitting region of the photomask will be reduced in accordance with the size of the device, but if the interval between the light-transmitting regions is reduced to a specific range (the exposure wavelength is 1/2) Or when the light passing through the reticle may be diffracted, interfered, etc., thereby affecting the resolution of the transferred pattern, causing deviations in the pattern on the photoresist, such as right-angled round-angled Corner rounded), line end shortened, and line width increase/decrease are all common photoresist pattern defects caused by optical proximity effects.

In order to solve the above problem, the prior art reduces light by forming an aid pattern (for example, a dummy pattern or a scattering bar) between layout patterns of integrated circuits on the photomask. The occurrence of resistance pattern defects. How to form a suitable auxiliary pattern to further form a desired layout pattern in the target layer is a subject that the related art desires to improve.

One of the objects of the present invention is to provide a method of correcting an auxiliary pattern to improve the accuracy of the reticle pattern and thereby form a desired layout pattern.

A preferred embodiment of the present invention provides a method of correcting an auxiliary pattern comprising 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. Then, a plurality of auxiliary patterns are added in the first layout pattern to form a second layout pattern, and at least one auxiliary pattern defining any edge of any adjacent first region is a selected pattern, and then the second layout is The pattern is divided into a plurality of second regions. Finally, a detecting step is performed on the second region having the selected pattern, and the second layout pattern is modified to form a corrected second layout pattern.

The invention is characterized in that before the optical proximity correction operation is performed on the layout pattern, the layout pattern is subjected to two division operations to improve the correctness of the added auxiliary pattern. In more detail, first, the layout pattern is first divided to form a plurality of first regions, and the auxiliary patterns of the boundaries of the adjacent first regions are selected as the selection pattern; then, the second division is performed, for example, expansion Include the first region of the selected pattern or translate the first region to form the second region such that the boundary of the second region does not overlap the selected pattern, and the second region includes a pattern different from the pattern included in the first region to further confirm the selection The relative relationship between the pattern and the adjacent pattern (especially the auxiliary pattern not originally included in the first area). According to this, the setting of the inappropriate auxiliary pattern can be avoided, and the correctness of the mask pattern can be improved to form the intended layout pattern.

10,12,14,16,18,20,22,24,26,28,30,301,302,303,304‧‧

100‧‧‧First layout pattern

102,104‧‧‧First area

106‧‧‧Second layout pattern

108,110‧‧‧Fixed second layout pattern

112,114‧‧‧Fixed first layout pattern

202,204,202’,204’‧‧‧Second area

D1‧‧‧ horizontal direction

I‧‧‧ spacing

IP‧‧‧ endpoint

L1, L2, L3, L4‧‧‧ edge

P1‧‧‧ pattern

P1’‧‧‧Auxiliary pattern

P1”‧‧‧Auxiliary pattern after correction

P11, S1'‧‧‧ modified sub-auxiliary pattern

P2‧‧‧ discriminant pattern

P2'‧‧‧ corrected discriminant pattern

P3, P4‧‧‧ modified auxiliary pattern

S1, S2, S3‧‧‧ select patterns

W‧‧‧Width

1 is a flow chart showing a method of modifying an auxiliary pattern according to a preferred embodiment of the present invention.

2 to 9 are schematic views showing a method of modifying an auxiliary pattern according to a preferred embodiment of the present invention.

Figure 10 is a flow chart showing a method of modifying an auxiliary pattern in accordance with a preferred embodiment of the present invention.

The present invention will be further understood by those of ordinary skill in the art to which the present invention pertains. .

Please refer to Figure 1. 1 is a flow chart showing a method of modifying an auxiliary pattern according to a preferred embodiment of the present invention. As shown in FIG. 1, first, step 10 is performed, and a first layout pattern is received by a computer system. The first layout pattern refers to a material layer (not shown) that is subsequently transferred to a photomask or a semiconductor wafer. For example, an ideal pattern of a photoresist layer, which includes a plurality of printable features, and the transferable patterns may include any feature pattern for forming an integrated circuit (IC). For example, a doped region pattern, an element pattern, a layout of a circuit, and the like. As the complexity of the feature pattern of the integrated circuit increases and the degree of integration increases, in order to reduce the computational load of the computer system and the operation time of the subsequent steps, step 12 may be performed, first dividing a first layout pattern into a plurality by a computer system. a 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, The subsequent processing steps are performed simultaneously by a plurality of computer systems to save computation processing time. In one embodiment, when the first layout pattern is a square having a length of 100 micrometers (μm), the first layout pattern is divided into 100 first regions arranged in a matrix, and each of the first regions is one side long. 10 micron square.

Since the distance between the transferability pattern and the adjacent another transferability pattern in the first layout pattern is not necessarily the same, if the first layout pattern is directly formed on the reticle, and the reticle is used for subsequent The lithography process, the amount of light transmitted on both sides of the transferable pattern may be different, that is, the pattern formed on the material layer will be shifted or deformed, therefore, A correct layout of the layout pattern onto the material layer, step 14 is performed, and a plurality of auxiliary patterns are added to the first layout pattern to form a second layout pattern. The auxiliary pattern is a non-printable feature, and in more detail, when a mask having a first layout pattern and the auxiliary patterns is used to perform a photosensitive layer on one of the wafers In the lithography process, only the pattern corresponding to the first layout pattern is formed on the material layer, and the pattern corresponding to the auxiliary pattern will not be formed on the material layer. In an embodiment, the first layout pattern includes a plurality of rectangular patterns, and the shape of the added auxiliary patterns is similar to the pattern of the first layout patterns to uniformize the pattern density of the second layout patterns, that is, when When the light source passes through the reticle having the second layout pattern, the amount of light transmission on both sides of each of the transferability patterns of the second layout pattern will be relatively uniform, so that the subsequent formation of the lithography process can form an expected layer on the material layer. Layout pattern. The size, shape, number and arrangement of the auxiliary patterns can be adjusted according to the process requirements. In addition, the size range and arrangement of the auxiliary patterns must conform to the rules of the process rule check (PRC) such as: criticality. Limits for critical dimensions and critical spaces. In an embodiment, the width of each auxiliary pattern is less than a specific value, that is, the maximum size of the pattern that the mask is not exposed in the lithography process, and is greater than the exposure limit of the mask manufacturing machine. The minimum size of the pattern formed by the mask manufacturing machine, and more specifically, the semiconductor process having a feature size of 20 nanometers (nm), for example, the maximum size of the pattern that is not exposed in the mask is substantially It is 32 nm, and the exposure limit of the reticle making machine is substantially about 13 nm, so the width of the auxiliary pattern is substantially between 13 nm and 32 nm, but not limited thereto.

In addition, in order to save the computing time of the computer system, the auxiliary pattern is preferably composed of a plurality of electric The brain system is simultaneously added to the first layout patterns of the respective first regions, that is, the present invention utilizes a plurality of computer systems to simultaneously correct the first layout patterns in the plurality of different first regions, respectively, and is correct The first layout patterns in the different first regions are subjected to independent correction processing to add the required auxiliary patterns. Subsequently, the first layout patterns and the auxiliary patterns of the respective first regions are recombined to form a second layout pattern. It is worth noting that, since each of the first regions only contains a part of the first layout pattern, and is different from the original 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 further cross-references the auxiliary patterns in the two adjacent first regions to confirm the first regions. The correctness of the auxiliary pattern. In order to shorten the time required to confirm the correctness of the auxiliary pattern, the present invention selects an auxiliary pattern adjacent to the edge of the first region for a subsequent first detecting step, in one embodiment, defining any edge contacting any of the first regions. At least one auxiliary pattern is a selected pattern. In other embodiments, at least one auxiliary pattern that is less than a defined value from any of the edges of any of the first regions may be defined as a selected pattern.

Next, proceeding to step 16, the second layout pattern is re-divided into a plurality of second regions. The method of dividing the second layout pattern into the plurality of second regions may include: a. changing the size of the first region to form the second region; or b. moving each of the original first regions in either direction to form the second region Or c. Select a pattern as a reference point and select a specific range.

Further, the edge of the second region that is re-segmented is preferably not in contact with any of the auxiliary patterns, and the pattern included in the single second region, that is, the first layout pattern and the auxiliary pattern included in the second region are different from the corresponding single first 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 further includes expanding the first area or reducing the first area, and the number of the second areas after the division may be different. In the first area, the second area may partially overlap the corresponding first area. For example, the method of expanding the first region includes moving at least one side line of each first region in any direction, particularly an edge of the first region that the auxiliary pattern contacts or is adjacent, and translates it as an edge of the second region. And the distance between the edge of each second region (re-segmentation) and the edge of the corresponding first region (original segmentation) (that is, the moving distance of the edge of the first region) is substantially greater than or equal to a specific value, and Making the area of the second area larger than the area of the first area; or, directly expanding the first area in situ, that is, moving each edge of each first area to form a corresponding second area, at this time, The number of the divided second regions is equal to the number of the first regions, and the second regions after the re-segmentation will partially overlap each other, for example, each of the first regions is a square having a side length of 10 micrometers, and each of the second regions is one side long. 13 micron square. Taking the selected pattern as a reference point, a specific range in the method of selecting a specific range to divide the second layout pattern includes a circular area in which a certain end of the selected pattern is a center, and a specific value is a radius. Wherein, the setting of the specific value may correspond to the size of the auxiliary pattern, for example, the specific value is substantially larger than a maximum side length of one of the auxiliary patterns, or corresponds to a critical line width of the auxiliary pattern, for example: a specific value Using a reticle for a lithography process, the maximum size of a pattern in the reticle that will not be exposed.

Then, step 18 is performed to perform a first detecting step on the second layout pattern, in particular, selecting a second region having the selected pattern to perform a first detecting step. It should be noted that, in a preferred embodiment, the auxiliary patterns of the second regions (including the selected patterns) are separately detected by a plurality of computer systems, that is, the present invention utilizes a plurality of computer systems to simultaneously separate Independently detecting the auxiliary patterns in each of the second regions (with the selected patterns therein) to confirm the auxiliary patterns, in particular, the rules for detecting whether the patterns conform to the processing rules of the auxiliary patterns, for example, the critical line width and the criticality of the auxiliary patterns The spacing is limited. In addition, in another preferred embodiment, the second region having the selected pattern may be directly screened for independent detection, for example, the second layout pattern is divided into 100 second regions, but only 50 of the second regions have To select a pattern, it is only necessary to use multiple computer systems to separately perform independent detection on the auxiliary patterns in the 50 second regions. Measure to confirm whether the auxiliary pattern conforms to the rule of the process rule detection of the auxiliary pattern; or directly, independently select the selected patterns in the 50 second regions. In addition, in another preferred embodiment, the method for performing the first detecting step may further include performing a first detecting step directly on the single selected pattern to confirm whether the selected pattern conforms to a rule of the process rule detection of the auxiliary pattern, for example: an auxiliary pattern. The critical line width and the critical spacing are limited, or the selected pattern and any auxiliary pattern adjacent to the selected pattern are first combined to form a discriminating pattern, and then the method for confirming whether the discriminating pattern conforms to the auxiliary pattern is detected.

When any of the auxiliary patterns, for example, the selection pattern or the discrimination pattern cannot pass the first detecting step, step 20 is performed to correct the second layout pattern to form a corrected second layout pattern. The method for correcting the second layout pattern comprises modifying the selected pattern, for example, increasing the side length of the selected pattern, so that the side length of the modified selected pattern is greater than the minimum length limit of the side length of the auxiliary pattern, so that the corrected selected pattern can reach the setting. The function of the auxiliary pattern is, for example, homogenizing the amount of light transmitted by the subsequently formed reticle; or reducing the side length of the selected pattern so that the side length of the modified selected pattern is smaller than the maximum size of the pattern that is not exposed in the reticle, That is to say, the modified selection pattern will not be formed on the target material layer through the subsequently formed photomask. Accordingly, the corrected second layout pattern includes the first layout pattern, a portion of the original auxiliary pattern, and the corrected selection pattern.

Similarly, the auxiliary patterns corresponding to the discrimination patterns may be respectively modified to form a plurality of modified sub-auxiliary patterns, and then the modified sub-auxiliary patterns are combined to form a corrected discrimination pattern, for example: When the length of the side of the pattern is larger than the maximum size of the pattern that is not exposed in the mask, the side length of the selected pattern is reduced and the side length of the auxiliary pattern of the adjacent selected pattern in the pattern is respectively determined to form a plurality of corrected a sub-auxiliary pattern (including the modified selected pattern and the modified auxiliary pattern), and then the corrected sub-auxiliary pattern is combined into the corrected discriminating pattern so that the corrected discriminating pattern does not pass through the subsequently formed mask It is formed on the target material layer. In other embodiments, the correction discrimination pattern may also only correct the selected pattern in the discrimination pattern and Any one of the auxiliary patterns adjacent to the selected pattern in the pattern is discriminated. Accordingly, the corrected second layout pattern includes the first layout pattern, a portion of the original auxiliary pattern, and the corrected discrimination pattern.

Next, proceeding to step 22, after correcting the auxiliary pattern (especially the selected pattern), performing at least one optical proximity correction (OPC) on the modified second layout pattern to form a corrected first layout. The pattern and a plurality of modified auxiliary patterns. The optical proximity correction (OPC) may include first collecting the widths of the geometric patterns (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 to the correction reference in the database, and the correction values of the geometric patterns are calculated to correct the line width, the end of the line, and the corner of each line segment in each geometric pattern. In general, the method of correction includes adjusting the line width of the line segment, or adding a pattern of auxiliary blocks such as a serif or a hammerhead at the end or corner of the line.

Then, step 24 is performed, that is, a second detecting step is performed to check whether the corrected first layout pattern and the corrected auxiliary pattern that complete the first detecting step and the optical proximity correction operation are respectively in accordance with the process rule detection of the layout pattern. The rule and the rule of the process rule detection of the auxiliary pattern are further confirmed to confirm the correctness of the corrected first layout pattern and the corrected auxiliary pattern. For example, through the simulation method of the computer system, a process rule is input, and the process rule detection is used to detect the straight end and the corner of each line segment in the corrected first layout pattern to determine whether the geometric patterns conform to the designed product. The critical dimension and critical space of the characteristic pattern of the bulk circuit or other rules governing the process design. When the corrected first layout pattern and the modified auxiliary pattern completely comply with the rules of the respective process rule detection, as shown in step 26, the corrected first layout pattern and the corrected auxiliary pattern may be output by the computer system to the first a reticle; however, if the corrected first layout pattern and/or the modified auxiliary pattern partially or completely does not conform to the rules of the process rule detection, the corrected first layout pattern and/or the corrected The auxiliary pattern is again utilized by the computer system to perform the aforementioned steps. Or all the corrections. Finally, as shown in step 28, a lithography process is performed on the material layer using the reticle to form the first layout pattern to a material layer, and the auxiliary patterns and the modified auxiliary patterns are not formed to the material layer. . The material layer includes a photoresist layer disposed on a wafer.

In addition, when the first detecting step as shown in step 18 is completed, and the second layout pattern passes through the detecting step, an optical proximity correction (OPC) step similar to the step 22 can be performed, that is, as shown in step 30. At least one optical proximity correction (OPC) is performed directly on the second layout pattern to form a modified first layout pattern and a plurality of modified auxiliary patterns. Subsequently, step 24 is performed in the same manner: checking whether the corrected first layout pattern and the modified auxiliary pattern respectively satisfy the rule 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) Rules, if yes, proceed to step 26: the computer system outputs the corrected first layout pattern and the modified auxiliary pattern to a mask, and if not, the corrected first layout pattern and/or the corrected auxiliary The pattern is again partially or completely re-corrected using the computer system in the aforementioned steps. Finally, as shown in step 28, the material layer is subjected to a lithography process using the reticle to form a first layout pattern to a material layer, and no auxiliary pattern is formed to the material layer.

In order to explain the above steps in more detail, please refer to FIG. 2 to FIG. 9 . FIG. 2 to FIG. 9 are schematic diagrams showing a method for modifying an auxiliary pattern according to a preferred embodiment of the present invention, and please refer to FIG. 1 . The various process steps of the preferred embodiment.

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 A layout pattern 100 includes a plurality of transferable patterns P1, that is, used to form a product A characteristic pattern of a body 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 thereto, the first layout pattern 100 may be divided into more first regions. The processing time of more subsequent steps is reduced, and each first region may comprise a transferability pattern of a different shape, number or arrangement.

Step 14: Add a plurality of auxiliary patterns to form a second layout pattern, and define at least one auxiliary pattern of any one of the adjacent first regions to be a selected pattern.

Next, as shown in FIG. 3, in order to prevent pattern defects caused by optical proximity effects from being formed on the material layer, a plurality of auxiliary patterns P1' are respectively added to different first regions 102/104 by different computer systems, and then The first region 102/104 having the auxiliary pattern is combined to form a second layout pattern 106, at which time both the pattern P1 and the auxiliary pattern P1' of the second layout pattern 106 have not undergone optical proximity correction (OPC) correction. The size, shape, number and arrangement of the auxiliary patterns P1' can be adjusted according to the process requirements. In the present 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 region 102 / 104 may be selected in advance to perform a subsequent detecting step, and the detecting step of the other auxiliary pattern P1 ′ is omitted to reduce the manufacturing time of the mask, wherein the detecting step is referred to The auxiliary pattern P1' in the two adjacent first regions 102/104 confirms the correctness of the auxiliary pattern P1' of each of the first regions 102/104. In the present embodiment, the auxiliary pattern P1' contacting the one side line L1 of the first region 102 is defined as a selection pattern S1. In other embodiments, the auxiliary pattern P1' of the second layout pattern 106 that is less than a defined value from the edge line L2 of the first region 104 may be the selected pattern S2. In addition, when two adjacent first regions 102/104 in the second layout pattern 106 respectively have an auxiliary pattern P1' as a selection pattern on both sides of the same edge line L1, only one of them is selected, for example: first The selection pattern S1 of the area 102 is used as the target pattern for the subsequent first detection step, and the subsequent detection step is skipped with the other one, for example, the selection pattern S3 of the first area 104 as the target pattern, to avoid double counting and increase the computer system. The load. The following embodiment will define the selection pattern S1 Description will be made as an embodiment of the target pattern.

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

Next, the second layout pattern 106 is divided into a plurality of second regions 202/204 such that the edge of the second region 202 does not directly contact the selected pattern S1, and the second region 202/204 includes 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' included in the corresponding first region 102/104. The method of dividing the second layout pattern 106 into the plurality of second regions 202/204 includes moving the first regions in either direction, for example, expanding the first region 102 having the selected pattern S1 to form the second region 202, as shown in FIG. As shown, the edge of the first region 102/104 is moved in a certain direction by a specific distance, for example, the edge L1 of the first region 102 is moved along a horizontal direction D1, that is, the first contact of the moving auxiliary pattern P1' (selection pattern S1). The edge line L1 of the region 102 is taken as the one side line L3 of the second region 202, and the distance between the edge line L3 of the second region 202 and the edge line L1 of the corresponding first region 102 is substantially greater than or equal to a specific value. Effectively confirming the correctness of the auxiliary pattern P1', the specific value may be greater than a maximum side length of the pattern of one of the auxiliary patterns P1' in the second layout pattern 106, preferably the critical line width of the auxiliary pattern P1', for example: using one When the reticle is subjected to a lithography process, the maximum size of a pattern that is not exposed in the reticle is more preferably the sum of a critical line width and a critical distance of the auxiliary pattern P1'. In this embodiment, only one right side line L1/L2 of each first area 102/104 is moved in the horizontal direction D1, while other original edges of each first area 102/104 are retained to make the second layout pattern 106 Different from the unit interval of the first layout pattern 100, in more detail, the left side line of the second area 202 is the original left side line of the corresponding first area 102, and the right side line is corresponding to the horizontal side. The right side line L1 of a region 102 is also the edge line L3. Similarly, the left side edge of the second area 204 is the original left side edge of the corresponding first area 104 (ie, the right side edge L1 of the first area 102), and the right side line is the corresponding first area 104 after the horizontal movement. The right side line L2 is also the side line L4. At this time, the distance between the edge line L3/L4 of each second region 202/204 and the edge line L1/L2 of the corresponding first region 102/104 is equal, and the total number of the second region is The area is equal to the total number of the first area, but the area occupied by each of the second areas 202/204 will be substantially larger than the area occupied by the corresponding first area 102/104, for example, the first area is one side long and 10 The micrometer square has a rectangular shape with a side length of 13 μm and a side length of 10 μm.

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

Moreover, in another embodiment, the selection may be made directly for the selected pattern. As shown in FIG. 5, the selected pattern S1 is taken as a reference point, and a circular area having the radius of the specific value is selected as a second area 202' as the center of the selected pattern S1, and the second area 202' is selected. The other patterns in the layout pattern 106 are defined as another second region 204'.

Step 18: Select a second region having a selected pattern to perform a first detecting step.

Next, the auxiliary patterns in the second regions 202/204 are simultaneously detected by the two computer systems to confirm the auxiliary patterns, in particular, whether the patterns S1, S2, and S3 are selected to conform to the rule of the process rule detection of the auxiliary patterns. For example, a first detecting step is performed on the second region 202 having the selected patterns S1, S3. The method of performing the first detecting step comprises performing a first detecting step directly on the selected pattern S1 to confirm whether the selected pattern S1 conforms to the rule of the process rule detection of the auxiliary pattern P1', for example: the critical line width and the critical spacing of the auxiliary pattern P1' Restriction, as well as auxiliary pattern P1' and transferable The limit of the distance between the sexual patterns P1. Alternatively, the selection pattern S1 and the auxiliary pattern P1' adjacent to the selection pattern S1 are merged, for example, the pattern S3 is selected to form a discrimination pattern P2, and it is confirmed whether the discrimination pattern P2 conforms to the process rule detection of the auxiliary pattern P1'.

Step 20: Correct the second layout pattern to form a modified second layout pattern.

When the selection pattern S1 or the discrimination pattern P2 cannot pass the first detecting step, the second layout pattern 106, that is, the correction selection pattern S1 or the discrimination pattern P2, needs to be corrected. Among them, the method of correcting the selection pattern S1 is explained as follows. Since the selection pattern S1 contacts the adjacent auxiliary pattern P1 ′ (the selection pattern S3 ) and does not conform to the auxiliary pattern process rule detection, the size of the selection pattern S1 can be reduced, for example, the width of the selection pattern S1 is reduced, or the selection is removed. The pattern S1 is such that the corrected auxiliary pattern P1" is, for example, a merged pattern of the corrected selected pattern S1 and the adjacent auxiliary pattern P1' (selected pattern S3), or the remaining adjacent auxiliary pattern P1' (selected pattern S3) The rules of the auxiliary pattern process rule detection may be met to form a modified second layout pattern 108, as shown in FIG.

Further, a method of correcting the discrimination pattern P2 will be described below. After the selection pattern S1 adjacent to the boundary of the first region 102/104, that is, the edge line L1 and the auxiliary pattern P1' (the selection pattern S3) are merged into the discrimination pattern P2, when the width W of the discrimination pattern P2 is substantially larger than the auxiliary pattern P1' When the critical line width is wide, the width W of the discrimination pattern P2 can be reduced, for example, the width of the selection pattern S1 is reduced to form the corrected sub-auxiliation pattern S1' and/or the width of the auxiliary pattern P1' of the composition discrimination pattern P2 is reduced to form a corrected Sub-auxiliary pattern P11, and then combining the modified sub-auxiliation patterns S1'/P11 to form a corrected discrimination pattern P2', so that the side length of the corrected discrimination pattern P2' is substantially smaller than that in the mask The maximum size of the exposed pattern conforms to the rules of the auxiliary pattern process rule detection to form a modified second layout pattern 110, as shown in FIG. At this time, the size of the corrected discrimination pattern P2' and the size of each of the auxiliary patterns P1' in the corrected second layout pattern 110 are still substantially larger than the size of any one of the patterns P1 of the first layout pattern 100.

Step 22: After the correction portion selects the pattern, optically adjacent correction (OPC) is performed on the modified second layout pattern to form a corrected first layout pattern and a plurality of modified auxiliary patterns.

After the correction portion selects the pattern S1 to improve the correctness of the auxiliary pattern P1', as shown in FIGS. 8 and 9, the line width of each line segment of each geometric pattern in the corrected second layout pattern 108/110 At least one optical proximity correction (OPC) correction is performed at the end of the line and at the corner to form a modified first layout pattern 112/114 and a plurality of modified auxiliary patterns P3/P4. At this time, the size of any of the modified auxiliary patterns P3/P4 will be substantially smaller than the size of any of the modified first layout patterns 112/114.

Step 24: Perform a second detecting step of checking whether the corrected first layout pattern and the corrected auxiliary pattern of the optical proximity correction operation and the corrected auxiliary pattern respectively conform to the rule of the process rule detection of the layout pattern and the auxiliary pattern Rules for process rule detection.

Step 26: The corrected first layout pattern and the modified auxiliary pattern are outputted by the computer system to a mask.

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

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

In short, please refer to Figure 10. Figure 10 is a flow chart showing a method of modifying an auxiliary pattern in accordance with 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 first utilizes a plurality of computer systems to separately perform independent correction processing on the layout patterns in the respective first regions to add the required auxiliary patterns, and then merge the plural patterns already having the auxiliary patterns. The first regions are formed 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, a plurality of computer systems are simultaneously used to simultaneously Separate detection is performed on the auxiliary patterns (including the selected patterns) in the respective second regions to confirm the auxiliary patterns, in particular, to confirm whether the selected patterns meet the rules of the process rule detection of the auxiliary patterns, and perform correction to obtain optical Near the final auxiliary pattern before 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 performs secondary pattern segmentation, the first pattern segmentation is to add the required auxiliary patterns in each of the first regions, and the second pattern segmentation is used to confirm each of the second regions. The auxiliary pattern, especially the selected pattern, conforms to the rules of the process rule detection of the auxiliary pattern.

In summary, the present invention is characterized in that before the optical proximity correction operation is performed on the layout pattern, the layout pattern is subjected to two division operations to improve the correctness of the added auxiliary pattern. In more detail, first, the layout pattern is first divided to form a plurality of first regions, and the auxiliary patterns of the boundaries of the adjacent first regions are selected as the selection pattern; then, the second division is performed, for example, expansion Include the first region of the selected pattern or translate the first region to form the second region such that the boundary of the second region does not overlap the selected pattern, and the second region includes a pattern different from the pattern included in the first region to further confirm the selection The relative relationship between the pattern and the adjacent pattern (especially the auxiliary pattern not originally included in the first area). According to this, the setting of the inappropriate auxiliary pattern can be avoided, and the correctness of the mask pattern can be improved to form the intended layout pattern.

10,12,14,16,18,20,22,24,26,28,30‧‧

Claims (20)

A method for 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; adding a plurality of auxiliary patterns in the first layout pattern to form a first Layout pattern, and defining at least one of the auxiliary patterns adjacent to any one of the edges of the first region as a selected pattern; dividing the second layout pattern into a plurality of second regions; and having the selected pattern The second area performs a detecting step; and the second layout pattern is modified to form a corrected second layout pattern. The method of modifying an auxiliary pattern according to claim 1, further comprising: performing at least one optical proximity correction (OPC) on the modified second layout pattern to form a corrected first layout pattern and a plurality A modified auxiliary pattern. The method of modifying an auxiliary pattern according to claim 2, wherein a size of any one of the modified auxiliary patterns is substantially smaller than a size of any one of the modified first layout patterns. The method for modifying an auxiliary pattern according to claim 2, further comprising: outputting, by the computer system, the corrected first layout pattern and the modified auxiliary pattern to a mask; and using the mask to a material layer A lithography process is performed to form the first layout pattern to the material layer. The method of modifying an auxiliary pattern according to claim 4, wherein the auxiliary patterns are not formed to the material Material layer. The method of modifying an auxiliary pattern according to claim 1, wherein the method of dividing the second layout pattern into the plurality of second regions comprises changing a size of at least one of the first regions to form the second region. The method of modifying an auxiliary pattern according to claim 6, wherein a distance between an edge of each of the second regions and the corresponding edge of the first region is substantially greater than or equal to a specific value. The method of modifying an auxiliary pattern according to claim 7, wherein the specific value is substantially greater than a maximum side length of one of the auxiliary patterns. The method of modifying an auxiliary pattern as claimed in claim 7, wherein the specific value is a lithography process using a mask, the maximum size of a pattern in the mask that is not exposed. The method of modifying an auxiliary pattern according to claim 1, wherein each of the second regions partially overlaps at least one corresponding first region. The method of modifying an auxiliary pattern according to claim 1, wherein the number of the second regions is substantially not equal to the number of the first regions. The method of modifying an auxiliary pattern according to claim 1, wherein the method of dividing the second layout pattern into the plurality of second regions comprises moving each of the first regions in either direction. The method of modifying an auxiliary pattern as claimed in claim 12, wherein an area of each of the second regions is substantially equal to an area of the corresponding first region. The method of modifying an auxiliary pattern according to claim 1, wherein the method of dividing the second layout pattern into a plurality of second regions comprises selecting a specific range by using the selected pattern as a reference point. The method of modifying an auxiliary pattern as claimed in claim 14, wherein the specific range comprises a circular area having a radius of a specific value of an end point of the selected pattern. The method of modifying an auxiliary pattern of claim 15, wherein the specific value is substantially greater than a maximum side length of one of the auxiliary patterns. The method of modifying an auxiliary pattern according to claim 1, wherein the detecting step comprises a rule of confirming whether the selected pattern conforms to a process rule check (PRC) of an auxiliary pattern. The method for modifying an auxiliary pattern according to claim 1, wherein the detecting step comprises: combining the selected pattern and any one of the auxiliary patterns adjacent to the selected pattern to form a discrimination pattern; and confirming whether the determination pattern conforms to a The rule of the process rule check (PRC) of the auxiliary pattern. The method of modifying an auxiliary pattern according to claim 18, wherein the method of modifying the second layout pattern comprises: respectively correcting the auxiliary patterns corresponding to the discrimination pattern to form a plurality of modified sub-auxiliary patterns; and combining the The modified sub-auxiliary pattern forms a corrected discriminant pattern. The method of modifying an auxiliary pattern according to claim 19, wherein in the corrected second layout pattern, the size of the corrected discrimination pattern and the size of each of the auxiliary patterns are substantially large The size of any of the first layout patterns.