KR100812090B1 - Mask pattern and the forming method thereof - Google Patents

Abstract

The present invention relates to a mask pattern and a method of forming a mask pattern, and more particularly, to a method of forming a mask pattern through predetermined pattern correction using a layout pattern including a plurality of subpatterns in a semiconductor manufacturing process. Forming a first result corrected by a predetermined rule based OPC in the pattern, and in accordance with each segment-zone divided by an extension line of the subpattern boundary line, Forming a second result corrected by the second result; and applying and correcting both the first result and the second result when both the first result and the second result exist in each segment zone. In accordance with the present invention, the fidelity improvement of the mask pattern of the final OPC results According to remove Tonbridge (Pattern bridge) in advance, and eopeojim unnecessary pattern there is an effect that it is possible to significantly improve the OPC correction speed.

Mask, Pattern, Optical Proximity Correction (OPC), Hybrid

Description

Mask pattern and the forming method

1 to 7 schematically show a method of forming a conventional mask pattern.

8 to 15 are diagrams showing a process diagram of one embodiment of a mask pattern and a mask pattern forming method according to the present invention.

16 shows a comparative example in a mask pattern forming method.

FIG. 17 is a diagram illustrating a mask pattern when only a Model based OPC is applied in a conventional mask pattern forming method. FIG.

18 is a view illustrating a conventional mask pattern forming method and a mask pattern forming method according to the present invention;

The present invention relates to a mask pattern and a method of forming a mask pattern, and more particularly, to Hybrid Proximity Correction (hereinafter referred to as "OPC") to which Model based OPC is applied after Rule based OPC.

In general, the OPC refers to a pattern for correcting the deformation value by calculating a value to be deformed in advance when the mask pattern is projected onto the substrate, and is also referred to as "proximity effect correction" and " optical proximity compensation".

When the OPC is described in more detail, an image of a layout pattern, which is a circuit pattern projected on a substrate, is different from the shape of an actual mask pattern when performing an exposure process using light diffraction. In particular, when the spacing of adjacent patterns on the mask is close, they affect each other, which causes a lot of difference from the design value. This phenomenon is called an optical proximity effect (OPE). Therefore, in order to correct the optical proximity effect, it is necessary to reinforce the size of the pattern or the edge of the mask to approximate the data of the mask through additional simulation to the CAD data for design.

In the early days of OPC, only the function of increasing or decreasing the line width of one-dimensional circuit patterns was possible, but now two-dimensional OPC is possible with shorter edges of the circuit patterns. Recently, Full Chip OPC that uses OPC to the periphery and core areas as well as the repetitive cell pattern is widely used.

OPC is divided into the case of presenting rule by pattern size (hereinafter referred to as "Rule based OPC") and the simulation based OPC (hereinafter referred to as "Model based OPC"). In the case of rule based OPC, OPC is easy. On the other hand, the accuracy is low, and in the case of Model-based OPC, the accuracy is high, but the data production is not easy, so the mask production is not easy. Generally, it is better to apply Rule based OPC because of the simple and repetitive circuit pattern in DRAM. In the case of LOGIC, Model based OPC method is recommended.

However, in order to obtain more accurate OPC results, hybrid OPCs that use Rule-based OPC and Model-based OPC are frequently used. Hybrid OPC aims to maximize satisfaction with OPC results by complementing each other's shortcomings.

Normally, Hybrid OPC applies Model based OPC after Rule based OPC. When Model based OPC is performed after Rule based OPC, unnecessary results are generated in some patterns, which increases the pattern complexity, which makes the mask around. Time (1 / Programmability, hereinafter referred to as "TAT") is degraded, and in severe cases, it may cause a pattern bridge, which is a phenomenon in which different patterns to be separated are attached. Hereinafter, the problems of the related art will be described in detail with reference to the accompanying drawings.

FIG. 1 is a diagram illustrating a layout pattern before OPC correction, and when there are patterns indicated by 11 and 12 in FIG. 1, the portions indicated by 13 and 14 are modified as described below according to the application of Rule based OPC. .

FIG. 2 is a diagram illustrating a deformation according to the application of Rule based OPC with respect to FIG. 1, and patterns such as 23, 24, and 25 are additionally generated. Accordingly, parts shown by 13 and 14 of FIG. Steps 21 and 22 resulted in STEP.

3 is a diagram illustrating a mask pattern generated by applying Model based OPC after Rule based OPC by a conventional mask pattern forming method.

That is, when the Rule based OPC result of FIG. 2 is used as an input of the Model based OPC, patterns such as 31, 34, 35, and 36 are generated in the layout patterns of 32 and 33.

However, 35 and 36 of FIG. 3 show unnecessary patterns generated by applying Model based OPC after Rule based OPC.

That is, according to the conventional mask pattern forming method, a rule-based OPC is applied to a layout pattern, and the resultant is input to the input of the model-based OPC, and an unwanted pattern is generated in the final OPC resultant. This result is due to a Model based OPC feature called division (hereinafter referred to as "dissection").

Model based OPC divides the layout pattern to be corrected to correct the pattern, and the segmented-zone segments are moved by applying the correction weight generated by the simulation result. If the correction weight is positive (+), the pattern is added, and if it is negative (-), the pattern is cut out, and if it is zero (0), the correction is not performed.

Hereinafter, the problems of the prior art will be described in more detail with reference to the drawings.

FIG. 4 illustrates a general model based OPC dissection applied to the layout pattern shown in FIG. 1. When a general model based OPC dissection is performed on the layout pattern, the dissection is performed as shown in FIG. 1, which is represented by 12, 41, 42, 43, 44, 45, 46, and 47 of FIG. 4. 41, 42, 46, and 47 are divided into segment-zones called "VERT" to prevent corner rounding of the pattern, and 43, 44, and 45 are related to the correction of the line width of the pattern. RUN "into the segment zone. Of these, "VERT" is divided into the same segment zone, different from "RUN" to solve corner rounding. 44 has a different size than 43 and 45 belonging to the same "RUN".

FIG. 5 is a diagram illustrating a general model based OPC applied after the dissection according to FIG. 4. When OPC is performed through the dissection as shown in FIG. 4, a corrected pattern such as 51, 52, 53, 55, 56, and 57 is generated in the layout pattern represented by 54. When the general model based OPC is made as shown in Figure 5 does not cause a problem.

However, the situation is different for Hybrid OPC, which is used to further compensate for things like etch bias in patterns such as isolated lines.

FIG. 6 illustrates a situation in which Dissection is performed on the result of Rule based OPC rather than the layout pattern because the Rule based OPC result becomes the INPUT of the Model based OPC. Accordingly, comparing FIG. 4 with FIG. 6, 61 in FIG. 6 has no change in dissection as in FIG. 4. However, 62, 63, 64, 65, 66 and 67 of FIG. 6 are moved to the pattern after the pattern is corrected due to the application of Rule based OPC. In particular, 68 and 69, in which the step (STEP) occurs in the pattern, are changed into segment zones completely different from those shown in 58 of FIG. 5 is divided into a segment zone called "RUN", but 68 and 69 of FIG. 6 are classified into a segment zone called "VERT" due to Rule based OPC.

That is, as the Model based OPC is applied after the rule based OPC, one "RUN" segment zone is changed into two "VERT" segment zones. As such, the segment zones increase after dissection.

FIG. 7 is a diagram illustrating a result of a pattern to which Model based OPC is applied to Dissection of FIG. 6. After rule based OPC, pattern correction such as 71, 72, 73, 74, 75 76, 77, and 78 of FIG.

However, 77 and 78 of FIG. 7 show that unnecessary and unwanted pattern correction is generated.

In addition, this increases the pattern complexity as described above, and worsens the mask fabrication TAT.

In particular, since an unnecessary pattern such as 78 of FIG. 7 may occur, a pattern bridge may occur, resulting in difficulty in process progression.

Therefore, the present invention not only prevents unwanted mask patterns from being generated in the final result of Hybrid Optical Correction Correction (OPC), but also prevents pattern bridges while maximizing pattern fidelity, the ultimate goal of OPC. It is an object of the present invention to provide a mask pattern and a mask pattern forming method that can reduce the TAT (Turn Around Time) when manufacturing a mask.

A mask pattern forming method according to the present invention for achieving the above object is a method for forming a mask pattern through a predetermined pattern correction using a layout pattern including a plurality of sub-pattern in the semiconductor manufacturing process, the layout pattern Forming a corrected first result by applying a predetermined rule based OPC to the predetermined pattern based OPC according to each segment-zone divided into extension lines of the subpattern boundary line in the layout pattern; Applying to form a corrected second result; And correcting by applying both the first result and the second result when both values of the first result and the second result exist in the respective segment zones.

In addition, the correcting by applying both the first result and the second result may be corrected by mutually canceling values of the first result and the second result for each segment zone.

The correcting by applying both the first resultant and the second resultant may be performed when the values of the first resultant and the second resultant for each segment zone are plus. The sum of the values of the first result and the second result can be added and corrected.

The correcting by applying both the first resultant and the second resultant may be performed when the value of the first resultant and the second resultant for each segment zone is both minus. The value of the first and second results can be trimmed and corrected.

In addition, the correcting by applying both the first result and the second result may be corrected by the value of the result which is not zero when only one of the first result and the second result is zero.

The correcting by applying both the first resultant and the second resultant may be performed by adjusting the value of the first resultant and the second resultant when one of the first resultant and the second resultant is positive and the other is negative. You can compensate by canceling each other out.

In addition, the step of applying and correcting both the first resultant and the second resultant is performed to add an additional correction if the values of mutually canceling the first resultant and the second resultant are positive, and if the result is negative, if not corrected, I can correct a cutting off.

In addition, the mask pattern according to the present invention for achieving the above object is characterized in that it is made by any one of the mask pattern forming method of the mask pattern forming method in the mask pattern in the semiconductor manufacturing process.

According to the present invention, it is possible to improve the fidelity of the mask pattern of the final OPC result, it is possible to remove the unwanted pattern bridge (Pattern bridge) in advance by the filtering process by performing the hybrid OPC, unnecessary As the pattern disappears, the OPC correction speed can be significantly improved, and if the OPC is made according to the method proposed in the present invention, the TAT (Turn Around Time), which takes a mask manufacturing time due to a significant reduction in the number of patterns, is reduced. There is an advantage that can be significantly shortened.

Hereinafter, an embodiment of a mask pattern and a mask pattern forming method according to the present invention will be described in detail with reference to the accompanying drawings.

In the present invention, when applying Model based OPC after Rule based OPC, Dissection about layout pattern is maintained and the rule based OPC result and Model based OPC result are canceled in each segment zone so that they appear in final result. There is this.

8 (a) is a diagram showing the original Dissection applied to the rule based OPC results as it is. Dissection applied here is the same as Dissection shown in FIG. 4 but has a different Dissection from that shown in FIG. 6 according to the prior art.

Each pattern divided by Dissection in the layout pattern is called a subpattern.

FIG. 8 (b) shows the rule pattern OPC in each segment zone while maintaining the Dissection for the layout pattern when applying the model based OPC after the rule based OPC which is the biggest feature of the mask pattern and the mask pattern forming method according to the present invention. This figure shows the process of adding the result and the Model based OPC result to the final result through calculation.

In detail, when the result of Rule based OPC is ⓐ (see FIG. 6) and the result of Model based OPC is ⓑ (see FIG. 5), the final result (ⓒ) is obtained by the following equation.

Ⓒ = (ⓐ + ⓑ) xⓚ.

However, if (ⓐ AND ⓑ) = 0 and ⓚ = 0, or (ⓐ AND ⓑ) ≠ 0, substitute ⓚ = 1 into ⓚ respectively to obtain the final result (ⓒ).

That is, if ⓐ and ⓑ are zero between each of the segment zones, and if any of the values of ⓐ and ⓑ is zero {(ⓐ AND ⓑ) = 0}, ⓚ = 0. If the corrected pattern does not appear and the values of ⓐ and ⓑ are both present {(ⓐ AND ⓑ) ≠ 0}, ⓚ = 1, and the final result (ⓒ) is a value of "ⓐ + ⓑ".

FIG. 9 is a diagram illustrating a process of OPC with Dissection for a layout pattern even after Rule based OPC.

10 to 14 are diagrams illustrating a process of applying Hybrid OPC by dividing a problem part after Rule based OPC as shown in 91, 92, 93, and 94 in FIG.

FIG. 10 is a diagram illustrating a process in which a hybrid OPC is applied to a portion 91 of FIG. 9 according to a mask pattern and a mask pattern forming method according to the present invention.

That is, in FIG. 10 (a), 101 is a result corrected by applying Rule based OPC (ⓐ, +) (see FIG. 6), and in FIG. 10 (b), 102 is corrected by applying Model based OPC (ⓑ). , 0) (see FIG. 5).

However, if any of the values of ⓐ and ⓑ is zero {(ⓐ AND ⓑ) = 0}, ⓚ = 0, and the final result ⓒ does not show a corrected pattern at all. There is no corrected value, such as 103 at (ⓒ = 0).

FIG. 11 is a diagram illustrating a process in which Hybrid OPC is applied to part 92 of FIG. 9 according to the present invention.

That is, in FIG. 11 (a), 111 is a correction result (ⓐ, +) to which Rule based OPC is applied as shown in 92 in FIG. 9, and the part indicated by 112 in FIG. The calibration result (ⓑ, 0) is applied to the model based OPC. Similarly, if any of the values of ⓐ and ⓑ is zero {(ⓐ AND ⓑ) = 0} and ⓚ = 0, the corrected pattern does not appear in the final result (ⓒ). There is no corrected value, such as 113 at (ⓒ = 0).

FIG. 12 is a diagram illustrating a process in which Hybrid OPC of part 93 of FIG. 9 is applied according to the present invention.

12 shows a different phenomenon from those in FIGS. 10 and 11.

12 (a) is a correction result (ⓐ, +) to which Rule based OPC is applied as indicated by 93 in FIG. 9, and a portion indicated by 122 in FIG. 12 (b) is included in the layout pattern. This is the correction result (ⓑ, +) applied to the model based OPC.

In this case, if both ⓐ and ⓑ have values {(ⓐ AND ⓑ) ≠ 0}, ⓚ = 1, and the final result (ⓒ) has a value of "ⓐ + ⓑ" as shown in 12 (c) 123. It is delivered.

FIG. 13 is a diagram illustrating a process in which Hybrid OPC is applied to a portion 94 of FIG. 9 according to the present invention.

That is, referring to the OPC process of 94 of FIG. 9, FIG. 13 (a) shows the correction result (ⓐ, +) to which the rule based OPC is applied, and FIG. 13 (b) shows that the Model based OPC for the layout pattern The applied correction results (ⓑ, +) are shown as 132, and FIG. 13 (c) shows the sum (ⓐ + ⓑ) for these results as 133. Again, as in the case of FIG. 12, when both ⓐ and ⓑ have values {(ⓐ AND ⓑ) ≠ 0}, ⓚ = 1, and the final result (ⓒ) is equal to 133 in 13 (c). The value of ⓐ + ⓑ "is passed.

FIG. 14 shows the results of OPC for each part from FIG. 10 to FIG. 13 collectively, and results are shown as 141, 142, 143, and 144.

15 is a view showing the final result of the mask pattern according to the present invention. As shown in FIG. 15, the mask pattern according to the present invention, unlike the mask pattern according to the related art of FIG. 7, shows that the unnecessary patterns 77 and 78 are not only disappeared but also excellent in terms of preventing the pattern bridge. As a result, the present invention has a filtering process that can prevent the pattern bridge phenomenon by dissection of the layout pattern rather than dissection of the rule based OPC result when performing the model based OPC after the rule based OPC (151 in FIG. 15). , 152). That is, the present invention produces a filtering effect according to the AND operation in the mask pattern process even though there is no separate filtering process.

16 is a diagram illustrating a mask pattern by an associated method without undergoing a filtering process. As shown in parts 161 and 162 of FIG. 16, the pattern bridge phenomenon is likely to occur because the filtering is not performed. As a result, according to the present invention, it can be seen that the filtering effect (151, 152 of FIG. 15) is more effective in preventing the pattern bridge.

17 illustrates a mask pattern when only a model based OPC is applied to a layout pattern. A space of 151 and 152 of FIG. 15, which is a mask pattern according to the present invention, may have the same value as that of 171 and 172 of FIG. 17 when only a model based OPC is applied. Therefore, the mask pattern according to the present invention has the advantage that can enjoy the effect of Model based OPC less pattern bridge occurs.

18 is a diagram illustrating a state in which a mask pattern is written (hereinafter, referred to as "Writing"). However, when the hybrid OPC according to the conventional method is applied, because of the disadvantage of pattern complexity in terms of mask production, as shown in FIG. 18 (a), eight patterns are written to write one pattern. There was a hassle to write.

However, if the pattern is Hybrid OPC according to the mask pattern and the mask pattern forming method according to the present invention as shown in Figure 18 (b), by writing five patterns has the effect that the TAT for the mask manufacturing can be significantly improved Occurs.

As described above, according to the mask pattern and the mask pattern forming method according to the present invention, the layout pattern is independent of the result of rule based OPC rather than applying a model based OPC by dissection to the rule based OPC result in the existing hybrid OPC. By maintaining the Dissection for the model, applying the model based OPC has the effect of improving the fidelity of the mask pattern of the final OPC results.

In addition, according to the present invention, the unwanted pattern bridge can be removed in advance by the filtering process by performing the hybrid OPC, and the OPC correction speed is excellent as the unnecessary pattern disappears. There are also benefits that can be improved.

In addition, according to the present invention, by significantly reducing the number of mask patterns, it is possible to significantly reduce the TAT required for the mask manufacturing time, thereby obtaining more customers, resulting in many time and economic benefits. It also works.

Claims (8)

In the method of forming a mask pattern through a predetermined pattern correction using a layout pattern including a plurality of sub-pattern in the semiconductor manufacturing process, Forming a corrected first result by applying a predetermined Rule based OPC to the layout pattern; Forming a corrected second result by applying a predetermined Model based OPC to the layout pattern according to each segment-zone divided by an extension line of the subpattern boundary line; And And correcting by applying both the first result and the second result when both values of the first result and the second result exist in each segment zone. According to claim 1, Correcting by applying both the first result and the second result is Mask pattern forming method, characterized in that for correcting by canceling the value of the first result and the second result for each segment zone. According to claim 1, Correcting by applying both the first result and the second result is If both the first result and the second result for each segment zone are positive, the first result and the second result for each segment zone are added and corrected. Mask pattern forming method. According to claim 1, Correcting by applying both the first result and the second result is If the value of the first result and the second result for each segment zone are both minus, the first result and the second result for each segment zone are trimmed as much as the sum of the values. Mask pattern forming method. The method of claim 1, Correcting by applying both the first result and the second result is If only one of the first result and the second result is zero, the mask pattern forming method characterized in that for correcting by the value of the non-zero result. According to claim 1, Correcting by applying both the first result and the second result is And if one of the first result and the second result is positive and the other is negative, the values of the first result and the second result cancel each other and correct the mask pattern. According to claim 1, Correcting by applying both the first result and the second result is A mask pattern forming method according to claim 1, wherein the first resultant and the second resultant are mutually corrected, and a correction is added when the values are positive. A mask pattern made by the mask pattern forming method according to any one of claims 1 to 7.

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