Model establishment method and system, layout correction method and device and storage medium

Abstract

The invention discloses a model establishment method and system, a layout correction method and device and a storage medium. The establishment method comprises the following steps: providing a plurality of test patterns; performing actual exposure on the test pattern to obtain an actual exposure pattern; acquiring optical characteristic parameters of the test pattern in the actual exposure process; etching along the actual exposure pattern to obtain an actual etching pattern; obtaining an etching deviation compensation value corresponding to the test pattern according to the actual etching pattern and the actual exposure pattern; and establishing an etching deviation compensation model in combination with the optical characteristic parameters of the test pattern and the etching deviation compensation value. According to the invention, accurate etching deviation compensation is facilitated.

Description

TECHNICAL FIELD

[0001] Embodiments of the present application relate to the field of semiconductor manufacturing, and in particular to a model establishing method and system, a layout correction method, an equipment and a storage medium. BACKGROUND

[0002] To realize the transfer of the pattern from the mask to the surface of the silicon wafer, it is usually necessary to go through the exposure step, the developing step after the exposure step and the etching step after the developing step. In the exposure step, light is irradiated onto the silicon wafer coated with photoresist through the light-transmitting area of the mask, and the photoresist undergoes chemical reaction under the irradiation of the light; in the developing step, the photoresist is developed to form a photoetching pattern based on the difference in the solubility of the developed and undeveloped photoresist to the developing agent, so as to realize the transfer of the pattern from the mask to the photoresist; in the etching step, the silicon wafer is etched based on the photoetching pattern formed by the photoresist layer, so as to further transfer the pattern of the mask to the silicon wafer.

[0003] However, as the size of the device is increasingly reduced, the difference between the pattern on the surface of the chip and the original mask pattern also increases after the photoetching process. In order to avoid the optical proximity effect from causing the pattern on the chip to be inconsistent with the mask pattern, the current solution is usually to compensate for the etching deviation of the mask pattern, and then to transfer the pattern according to the mask pattern compensated for the etching deviation.

[0004] However, the correction accuracy of the etching deviation compensation still needs to be improved. SUMMARY

[0005] The problem solved by the embodiments of the present application is to provide a method and system for establishing an etching deviation compensation model, a layout correction method, an equipment and a storage medium, which are beneficial to more accurate etching deviation compensation.

[0006] To solve the above problem, the embodiments of the present application provide a method for establishing an etching deviation compensation model, which comprises the following steps: providing a plurality of test patterns; performing actual exposure on the test patterns to obtain actual exposure patterns; obtaining optical characteristic parameters of the test patterns in the actual exposure process; etching along the actual exposure patterns to obtain actual etching patterns; obtaining etching deviation compensation values corresponding to the test patterns according to the actual etching patterns and the actual exposure patterns; and establishing an etching deviation compensation model in combination with the optical characteristic parameters of the test patterns and the etching deviation compensation values.

[0007] Optionally, in the step of obtaining etching deviation compensation values corresponding to the test patterns according to the actual etching patterns and the actual exposure patterns, the size difference between the actual exposure patterns and the actual etching patterns is obtained as the etching deviation compensation values.

[0008] Optionally, in the step of acquiring the optical characteristic parameter of the test pattern in the actual exposure process, the image logarithmic slope of the test pattern in the actual exposure process is acquired; and in the step of establishing the etching deviation compensation model by combining the optical characteristic parameter of the test pattern and the etching deviation compensation value, the etching deviation compensation model is established by combining the image logarithmic slope of the test pattern and the etching deviation compensation value.

[0009] Optionally, the step of establishing the etching deviation compensation model by combining the image logarithmic slope of the test pattern and the etching deviation compensation value comprises: performing function fitting on the multiple image logarithmic slopes of the test pattern and the etching deviation compensation values to obtain a function function of layout correction.

[0010] Optionally, the step of performing function fitting on the multiple image logarithmic slopes of the test pattern and the etching deviation compensation values to obtain a function function of layout correction comprises: setting a polynomial fitting function with the image logarithmic slope as the independent variable and the etching deviation compensation value as the dependent variable; and fitting the polynomial fitting function according to the multiple image logarithmic slopes of the test pattern and the etching deviation compensation values to obtain fitting coefficients of the polynomial fitting function, so as to obtain the polynomial fitting function as the function function of layout correction.

[0011] Optionally, in the step of fitting the polynomial fitting function according to the multiple image logarithmic slopes of the test pattern and the etching deviation compensation values to obtain fitting coefficients of the polynomial fitting function, so as to obtain the polynomial fitting function as the function function of layout correction, the expression of the function function comprises: Wherein, x is the image logarithmic slope, and f(x) is the etching deviation compensation value.

[0012] Optionally, the test pattern comprises a metal layer blocking pattern in the step of providing multiple test patterns.

[0013] Correspondingly, the embodiment of the present application further provides a layout correction method, comprising: providing a target pattern; acquiring an optical characteristic parameter of the target pattern under a preset exposure condition; obtaining an etching deviation compensation value corresponding to the target pattern according to the optical characteristic parameter and an etching deviation compensation model obtained by the method for establishing the etching deviation compensation model provided by the embodiment of the present application; and obtaining a layout pattern corresponding to the target pattern according to the etching deviation compensation value and the target pattern.

[0014] Optionally, in the step of acquiring the optical characteristic parameter of the target pattern under the preset exposure condition, the optical characteristic comprises an image logarithmic slope.

[0015] Optionally, the step of obtaining the layout pattern corresponding to the target pattern according to the etching deviation compensation value and the target pattern comprises: taking the sum of the size of the target pattern and the etching deviation compensation value as the size of the layout pattern.

[0016] Optionally, the target pattern includes a metal layer blocking pattern.

[0017] Correspondingly, the embodiment of the present application further provides a system for establishing an etching deviation compensation model, comprising: a test pattern providing module configured to provide a plurality of test patterns; an actual exposure module configured to perform actual exposure on the test patterns to obtain actual exposure patterns; an optical characteristic parameter obtaining module configured to obtain optical characteristic parameters of the test patterns in the actual exposure process; an actual etching module configured to perform etching along the actual exposure patterns to obtain actual etching patterns; an etching deviation compensation value obtaining module configured to obtain etching deviation compensation values corresponding to the test patterns according to the actual etching patterns and the actual exposure patterns; and an etching deviation compensation model obtaining module configured to establish an etching deviation compensation model in combination with the optical characteristic parameters of the test patterns and the etching deviation compensation values.

[0018] Correspondingly, the embodiment of the present application further provides a device comprising at least one memory and at least one processor, the memory storing one or more computer instructions, wherein the one or more computer instructions are executed by the processor to implement the method for establishing an etching deviation compensation model provided by the embodiment of the present application.

[0019] Correspondingly, the embodiment of the present application further provides a storage medium, the storage medium storing one or more computer instructions, the one or more computer instructions being used to implement the method for establishing an etching deviation compensation model provided by the embodiment of the present application.

[0020] Compared with the prior art, the technical scheme of the embodiment of the present application has the following advantages:

[0021] In the method for establishing an etching deviation compensation model provided by the embodiment of the present application, the etching deviation compensation model is established in combination with the optical characteristic parameters of the test patterns and the etching deviation compensation values; in the embodiment of the present application, the etching deviation compensation model is established according to the optical characteristic parameters and the etching deviation compensation values, the compensation strategy established based on the optical characteristic parameters can take the optical effect into account, which is beneficial to obtaining a more accurate etching deviation compensation model, thereby being beneficial to performing more accurate etching deviation compensation.

[0022] According to the optical characteristic parameter, the etching deviation compensation model obtained by the etching deviation compensation model establishment method provided in the embodiment of the present application is used to obtain the etching deviation compensation value corresponding to the target pattern, and the etching deviation compensation value and the target pattern are used to obtain the layout pattern corresponding to the target pattern; in the embodiment of the present application, the etching deviation compensation model is established according to the optical characteristic parameter and the etching deviation compensation value, and the compensation strategy established based on the optical characteristic parameter can take the optical effect into account, which is beneficial to obtain a relatively accurate etching deviation compensation model, thereby being beneficial to perform relatively accurate etching deviation compensation; and the etching deviation compensation value corresponding to the target pattern obtained according to the etching deviation compensation model provided in the embodiment of the present application is relatively accurate, thereby being beneficial to obtain a layout pattern with relatively accurate pattern size. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 is a flowchart of a layout correction method;

[0024] Figure 2 is a schematic diagram corresponding to each step in the layout correction method;

[0025] Figure 3 is a flowchart of an embodiment of the etching deviation compensation model establishment method of the present application;

[0026] Figure 4 is a correlation diagram of the etching deviation compensation value-image logarithmic slope in an embodiment of the etching deviation compensation model establishment method of the present application;

[0027] Figure 5 is a flowchart of an embodiment of the layout correction method of the present application;

[0028] Figure 6 is a functional block diagram of an embodiment of the etching deviation compensation model establishment system of the present application;

[0029] Figure 7 is a hardware structure diagram of an embodiment of the device provided by the present application. DETAILED DESCRIPTION

[0030] At present, it is difficult to perform relatively accurate etching deviation compensation, and the reasons why it is difficult to perform relatively accurate etching deviation compensation are analyzed in combination with a layout correction method.

[0031] Figure 1 is a flowchart of a layout correction method; Figure 2 is a schematic diagram corresponding to each step in the layout correction method.

[0032] In combination with reference Figure 1 and Figure 2 , the layout correction method comprises:

[0033] Step s1: providing a target pattern;

[0034] Step s2: selecting an etching deviation compensation value corresponding to the target pattern from an etching deviation compensation table;

[0035] Step s3: obtaining a layout pattern corresponding to the target pattern according to the etching deviation compensation value and the target pattern;

[0036] Step s4: exposing the layout pattern to a photoresist layer 100.

[0037] In the process of exposing the layout pattern to the photoresist layer 100, due to the influence of optical effect, the pattern side-wall in the photoresist layer 100 presents a slope, the measured pattern size is the middle CD at the half height of the photoresist layer 100, while in the process of transferring the pattern in the photoresist layer 100 to the etching layer 200 and then to the pattern layer 300, it is determined by the bottom CD of the pattern in the photoresist layer 100, and the etching deviation compensation is determined by the difference between the etching pattern size and the exposed pattern size, therefore, the actual etching deviation compensation value is affected by the optical effect, and the etching deviation compensation value corresponding to the target pattern is selected from the etching deviation compensation table in the prior art, without considering the influence of the optical effect, therefore, it is difficult to perform relatively accurate etching deviation compensation at present.

[0038] To solve the technical problem, the embodiment of the present application provides a method for establishing an etching deviation compensation model. Figure 1 Figure 1 shows a flowchart of the method for establishing the etching deviation compensation model according to the embodiment of the present application.

[0039] In the embodiment, the optical proximity correction method comprises the following basic steps:

[0040] Step S1: providing a plurality of test patterns;

[0041] Step S2: performing actual exposure on the test patterns to obtain actual exposure patterns;

[0042] Step S3: obtaining optical characteristic parameters of the test patterns in the actual exposure process;

[0043] Step S4: etching along the actual exposure patterns to obtain actual etching patterns;

[0044] Step S5: obtaining etching deviation compensation values corresponding to the test patterns according to the actual etching patterns and the actual exposure patterns;

[0045] Step S6: establishing an etching deviation compensation model in combination with the optical characteristic parameters of the test patterns and the etching deviation compensation values.

[0046] The method for establishing the etching deviation compensation model provided by the embodiment of the present application combines the optical characteristic parameters of the test patterns and the etching deviation compensation values to establish the etching deviation compensation model. In the embodiment of the present application, the etching deviation compensation model is established according to the optical characteristic parameters and the etching deviation compensation values. The compensation strategy based on the optical characteristic parameters can take the optical effect into account, which is conducive to obtaining a more accurate etching deviation compensation model, thereby facilitating more accurate etching deviation compensation.

[0047] In order to make the above objectives, characteristics and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application will be described in detail below with reference to the drawings.

[0048] Figure 4 FIG. 1 is a schematic diagram of the correlation between the etching deviation compensation values and the image logarithmic slopes in the method for establishing the etching deviation compensation model according to an embodiment of the present application.

[0049] In combination with reference Figure 3 and Figure 4 , step S1 is performed: providing a plurality of test patterns.

[0050] The test patterns are used to form target patterns to be transferred onto a wafer.

[0051] The etching deviation compensation model established by the establishing method of the embodiment is applicable in the step of performing optical proximity correction processing.

[0052] Specifically, in the semiconductor field, it is usually necessary to perform corresponding processing on the edges of the target patterns according to different environments in which the target patterns are located. In the embodiment, in the process of optical proximity correction processing, in order to realize the transfer of the target patterns onto the wafer, it is usually necessary to obtain a mask according to the target patterns, and then perform an exposure and development step using the mask, and then perform an etching step. After the photolithography process and the etching process, the transfer of the target patterns onto the wafer is completed, and the critical dimension of the pattern formed on the wafer has deviation from the critical dimension of the target pattern. Therefore, etching deviation compensation needs to be performed when the mask is obtained according to the target patterns.

[0053] In the embodiment, the test patterns in the plurality of test patterns include metal layer cut patterns.

[0054] The metal layer cut (M0 cut) patterns are used to cut the metal layer so as to electrically isolate the metal layer. Therefore, the number of the metal layer cut patterns is usually large and the size of the patterns is small, and thus the etching deviation has a greater impact on the metal layer cut patterns. Therefore, the method for establishing the etching deviation compensation model of the embodiment is particularly suitable for the metal layer cut patterns.

[0055] Step S2 is performed: performing actual exposure on the test patterns to obtain actual exposure patterns.

[0056] The actual exposure is performed on the test pattern, and an exposed and developed pattern (ADI) is obtained in the photoresist, which is an actual exposure pattern, and the actual exposure pattern is used for subsequent etching to obtain an actual etching pattern.

[0057] Specifically, in the embodiment, the actual exposure is performed on the test pattern to obtain an actual exposure pattern, including: obtaining a layout pattern according to the test pattern; obtaining a mask according to the layout pattern; and performing exposure and development by using the mask to obtain the actual exposure pattern.

[0058] Step S3 is performed: obtaining optical characteristic parameters of the test pattern in the actual exposure process.

[0059] The optical characteristic parameters of the test pattern in the actual exposure process are obtained, which are used to consider the influence of optical effects in the establishment of the etching bias compensation model.

[0060] In the embodiment, the image log slope of the test pattern in the actual exposure process is obtained in the obtaining of the optical characteristic parameters of the test pattern in the actual exposure process.

[0061] The image log slope (ILS) is related to the reaction of the photoresist and the light source at the edge of the actual exposure pattern in the exposure and development process, and thus the image log slope has an influence on the formation of the side wall of the actual exposure pattern, and thus the image log slope has an influence on the numerical value of the etching bias compensation. Therefore, in the embodiment, the image log slope of the test pattern in the actual exposure process is obtained in the obtaining of the optical characteristic parameters of the test pattern in the actual exposure process, which is used as a consideration of the optical effects to establish the etching bias compensation model, and thus a more accurate etching bias compensation model can be established.

[0062] Specifically, in the embodiment, the expression of the image log slope is wherein I Edge and are the light intensity and its slope at the edge of the pattern, respectively.

[0063] In the embodiment, the image log slope of the test pattern in the actual exposure process is obtained, including: obtaining the image log slope of the test pattern in the actual exposure process according to the mask and the exposure system.

[0064] Step S4 is performed: etching along the actual exposure pattern to obtain an actual etching pattern.

[0065] The actual etching pattern is obtained by etching along the actual exposure pattern, and the actual etching pattern is a structure of the target pattern transferred to the wafer.

[0066] Specifically, in the embodiment, in the process of etching along the actual exposure pattern to obtain the actual etching pattern, due to the influence of the etching process, the critical dimension of the pattern of the structure formed on the wafer has etching bias with the critical dimension of the target pattern, therefore, etching bias compensation is needed for the target pattern to obtain a more accurate actual etching pattern.

[0067] Step S5 is performed: according to the actual etching pattern and the actual exposure pattern, an etching bias compensation value corresponding to the test pattern is obtained.

[0068] In the process of transferring the actual exposure pattern to the wafer, due to the influence of the etching process, the critical dimension of the pattern of the structure formed on the wafer has etching bias with the critical dimension of the target pattern, therefore, according to the actual etching pattern and the actual exposure pattern, an etching bias compensation value corresponding to the test pattern is obtained to establish an etching bias compensation model according to the actual etching bias compensation value.

[0069] Specifically, in the embodiment, according to the actual etching pattern and the actual exposure pattern, an etching bias compensation value corresponding to the test pattern is obtained, and the size difference between the actual exposure pattern and the actual etching pattern is obtained as the etching bias compensation value.

[0070] Step S6 is performed: an etching bias compensation model is established in combination with the optical characteristic parameter of the test pattern and the etching bias compensation value.

[0071] In the embodiment, the etching bias compensation model is established according to the optical characteristic parameter and the etching bias compensation value, and the compensation strategy established based on the optical characteristic parameter can take the optical effect into account, which is beneficial to obtain a more accurate etching bias compensation model, thereby being beneficial to perform more accurate etching bias compensation.

[0072] Correspondingly, in the embodiment, the etching bias compensation model is established in combination with the optical characteristic parameter of the test pattern and the etching bias compensation value, and the etching bias compensation model is established in combination with the image log slope of the test pattern and the etching bias compensation value.

[0073] The image log slope of the test pattern in the actual exposure process is obtained to be used as the consideration of the optical effect to establish the etching bias compensation model, which is beneficial to establish a more accurate etching bias compensation model, therefore, the etching bias compensation model is established in combination with the image log slope of the test pattern and the etching bias compensation value, which is beneficial to take the influence of the optical effect into account and establish a more accurate etching bias compensation model.

[0074] In the embodiment, the etching deviation compensation model is established by combining the image log slope of the test pattern and the etching deviation compensation value, including: performing function fitting on the multiple image log slopes and the etching deviation compensation values of the test pattern to obtain a function function of layout correction.

[0075] As known from the foregoing, the image log slope has an influence on the numerical value of the etching deviation compensation, therefore, the function function of layout correction obtained by performing function fitting on the multiple image log slopes and the etching deviation compensation values of the test pattern can represent the etching deviation compensation model considering the influence of the optical effect.

[0076] In the embodiment, the function fitting on the multiple image log slopes and the etching deviation compensation values of the test pattern to obtain a function function of layout correction includes: setting a polynomial fitting function with the image log slope as the independent variable and the etching deviation compensation value as the dependent variable.

[0077] As an example, in the embodiment, the expression of the polynomial fitting function is f(x)=Ax 3 +Bx 2 +Cx+D, where x is the image log slope, f(x) is the etching deviation compensation value, and A, B, C and D are the fitting coefficients of the polynomial fitting function.

[0078] In other embodiments, the polynomial fitting function can also be set to a higher-order polynomial or a lower-order polynomial.

[0079] In the embodiment, the fitting coefficients of the polynomial fitting function are obtained by fitting the polynomial fitting function according to the multiple image log slopes and the etching deviation compensation values of the test pattern, so as to obtain the polynomial fitting function as the function function of layout correction.

[0080] As an example, in the embodiment, the polynomial fitting function f(x)=Ax 3 +Bx 2 +Cx+D is used, and the fitting coefficients A, B, C and D of the polynomial fitting function are obtained by fitting the polynomial fitting function according to the multiple image log slopes and the etching deviation compensation values, so as to obtain the polynomial fitting function as the function function of layout correction.

[0081] As an example, in the embodiment, the test pattern in the plurality of test patterns includes a metal layer isolation pattern, and the expression of the function function includes: Wherein, x is the image logarithmic slope, f(x) is the etching deviation compensation value.

[0082] It should be noted that, in combination with reference Figure 4 , Figure 4 is the correlation diagram of the etching deviation compensation value and the image logarithmic slope in the embodiment, wherein the abscissa is the image logarithmic slope, the ordinate is the etching deviation compensation value, the point diagram is the etching deviation compensation value-image logarithmic slope point diagram corresponding to a plurality of test patterns, it can be seen that the etching deviation compensation value and the image logarithmic slope have correlation, therefore, it is reasonable to establish the etching deviation compensation model according to the image logarithmic slope, the straight line in the figure illustrates the average value of the etching deviation compensation, and the curve in the figure illustrates the function function of the etching deviation compensation model, it can be seen that the etching deviation compensation model obtained by the establishing method of the embodiment is relatively accurate and has good applicability.

[0083] Correspondingly, the application also provides a layout correction method. Figure 5 is a flowchart of an embodiment of the layout correction method of the application.

[0084] Reference Figure 5 , execute step T1: provide a target pattern.

[0085] The target pattern is used for subsequent transfer to the wafer to form a structure on the wafer.

[0086] Specifically, in the semiconductor field, it is usually necessary to perform corresponding processing on the edges of the target pattern according to different environments in which the target pattern is located, in the embodiment, in the process of optical proximity correction, in order to realize the transfer of the target pattern to the wafer, it is usually necessary to obtain a mask according to the target pattern, and then use the mask to perform an exposure and development step, and then perform an etching step, after the photolithography process and the etching process, the target pattern is transferred to the wafer, and the critical dimension of the pattern formed on the wafer has deviation from the critical dimension of the target pattern, therefore, the layout correction method of the embodiment is used to perform etching deviation compensation when the mask is obtained according to the target pattern.

[0087] In the embodiment, the target pattern in the provided target pattern includes a metal layer cut pattern.

[0088] The metal layer cut (M0 cut) pattern is used to cut the metal layer so that the metal layer is electrically isolated, therefore, the metal layer cut pattern usually has a large number and small size, and the etching deviation has a greater impact on the metal layer cut pattern, so that the layout correction method of the embodiment is particularly suitable for the metal layer cut pattern.

[0089] Execute step T2: obtain the optical characteristic parameters of the target pattern under a preset exposure condition.

[0090] The optical characteristic parameter of the target pattern under the preset exposure condition is acquired, which is used to obtain the etching deviation compensation value of the target pattern according to the light characteristic parameter.

[0091] In the embodiment, the optical characteristic parameter of the target pattern under the preset exposure condition includes the image log slope.

[0092] The image log slope is related to the reaction between the photoresist and the light source at the edge of the actual exposure pattern in the exposure and development process, and thus the image log slope has an influence on the formation of the side-wall of the actual exposure pattern, and thus the image log slope has an influence on the value of the etching deviation compensation. Therefore, in the embodiment, the optical characteristic parameter of the target pattern under the preset exposure condition includes the image log slope, which is used to obtain the etching deviation compensation value, and thus the layout correction can be performed more accurately.

[0093] The step T3 is performed: the etching deviation compensation value corresponding to the target pattern is obtained according to the optical characteristic parameter and the etching deviation compensation model obtained by the method for establishing the etching deviation compensation model provided in the foregoing embodiments.

[0094] In the embodiment, the etching deviation compensation model is established according to the optical characteristic parameter and the etching deviation compensation value. The compensation strategy established based on the optical characteristic parameter can consider the optical effect, and thus the etching deviation compensation model obtained more accurately, and thus the etching deviation compensation can be performed more accurately, and thus the layout pattern corresponding to the target pattern obtained according to the etching deviation compensation value is more accurate, and thus the pattern size of the layout pattern is more accurate.

[0095] The step T4 is performed: the layout pattern corresponding to the target pattern is obtained according to the etching deviation compensation value and the target pattern.

[0096] The layout pattern corresponding to the target pattern is obtained according to the etching deviation compensation value and the target pattern, so as to perform the etching deviation compensation on the target pattern, and thus the deviation possibly caused by the photolithography process and the etching process is compensated in the layout pattern in advance, and thus the matching degree between the pattern formed on the wafer after the photolithography and etching processes and the target pattern is improved.

[0097] Specifically, in the embodiment, the layout pattern corresponding to the target pattern is obtained according to the etching deviation compensation value and the target pattern, including: the sum of the size of the target pattern and the etching deviation compensation value is used as the size of the layout pattern.

[0098] Correspondingly, the application further provides a system for establishing an etching deviation compensation model. Figure 6is a functional block diagram of an embodiment of the etching deviation compensation model establishment system of the present application.

[0099] Reference Figure 6 The etching deviation compensation model establishment system 50 comprises: a test layout providing module 501 configured to provide a plurality of test patterns; an actual exposure module 502 configured to perform actual exposure on the test patterns to obtain actual exposure patterns; an optical characteristic parameter acquisition module 503 configured to acquire optical characteristic parameters of the test patterns in the actual exposure process; an actual etching module 504 configured to perform etching along the actual exposure patterns to obtain actual etching patterns; an etching deviation compensation value acquisition module 505 configured to acquire etching deviation compensation values corresponding to the test patterns according to the actual etching patterns and the actual exposure patterns; and an etching deviation compensation model acquisition module 506 configured to establish an etching deviation compensation model in combination with the optical characteristic parameters of the test patterns and the etching deviation compensation values.

[0100] The test layout providing module 501 is configured to provide a plurality of test patterns.

[0101] The test patterns are used to form target patterns to be transferred onto a wafer.

[0102] The etching deviation compensation model established by the establishment method of the present embodiment is applicable in the step of performing optical proximity correction processing.

[0103] Specifically, in the semiconductor field, it is generally necessary to perform corresponding processing on the edges of target patterns according to different environments in which the target patterns are located. In the present embodiment, in the process of optical proximity correction processing, in order to realize the transfer of target patterns onto a wafer, a mask is generally obtained according to the target patterns, and then the mask is used to perform an exposure and development step, followed by an etching step. After the photolithography process and the etching process, the transfer of the target patterns onto the wafer is completed, and the critical dimension of the pattern formed on the wafer has deviation from the critical dimension of the target pattern. Therefore, etching deviation compensation needs to be performed when the mask is obtained according to the target patterns.

[0104] In the present embodiment, the test patterns provided in the plurality of test patterns comprise metal layer cut patterns.

[0105] The metal layer cut (M0 cut) patterns are used to cut metal layers so as to electrically isolate the metal layers. Therefore, the number of metal layer cut patterns is generally large and the size of the metal layer cut patterns is small, and thus the influence of etching deviation on the metal layer cut patterns is large. Therefore, the etching deviation compensation model establishment method of the present embodiment is particularly suitable for metal layer cut patterns.

[0106] The actual exposure module 502 is configured to perform actual exposure on the test patterns to obtain actual exposure patterns.

[0107] The test pattern is actually exposed to obtain an exposed and developed pattern (ADI) in the photoresist, that is, an actual exposure pattern, and the actual exposure pattern is used for subsequent etching to obtain an actual etching pattern.

[0108] Specifically, in the embodiment, the actual exposure of the test pattern is performed to obtain the actual exposure pattern, including: obtaining a layout pattern according to the test pattern; obtaining a mask according to the layout pattern; and performing exposure and development by using the mask to obtain the actual exposure pattern.

[0109] The optical characteristic parameter acquisition module 503 is configured to acquire the optical characteristic parameter of the test pattern in the actual exposure process.

[0110] The optical characteristic parameter of the test pattern in the actual exposure process is acquired to consider the influence of the optical effect in the establishment of the etching deviation compensation model.

[0111] In the embodiment, the image log slope of the test pattern in the actual exposure process is acquired as the optical characteristic parameter of the test pattern in the actual exposure process.

[0112] The image log slope (ILS) is related to the reaction between the photoresist and the light source at the edge of the actual exposure pattern in the exposure and development process, and thus the image log slope has an influence on the formation of the side-wall of the actual exposure pattern, and thus the image log slope has an influence on the numerical value of the etching deviation compensation. Therefore, in the embodiment, the image log slope of the test pattern in the actual exposure process is acquired as the optical characteristic parameter of the test pattern in the actual exposure process to establish the etching deviation compensation model by considering the optical effect, which is beneficial to establishing a more accurate etching deviation compensation model.

[0113] Specifically, in the embodiment, the expression of the image log slope is wherein, I Edge and are the light intensity and the slope thereof at the edge of the pattern, respectively.

[0114] In the embodiment, the image log slope of the test pattern in the actual exposure process is acquired, including: acquiring the image log slope of the test pattern in the actual exposure process according to the mask and the exposure system.

[0115] The actual etching module 504 is configured to etch along the actual exposure pattern to obtain an actual etching pattern.

[0116] The actual etching pattern is obtained by etching along the actual exposure pattern, and the actual etching pattern is a structure of the target pattern transferred to the wafer.

[0117] Specifically, in the embodiment, in the process of etching along the actual exposure pattern to obtain the actual etching pattern, due to the influence of the etching process, the critical dimension of the pattern of the structure formed on the wafer has etching bias with the critical dimension of the target pattern, therefore, etching bias compensation is needed for the target pattern to obtain a more accurate actual etching pattern.

[0118] The etching bias compensation value acquisition module 505 is configured to obtain the etching bias compensation value corresponding to the test pattern according to the actual etching pattern and the actual exposure pattern.

[0119] In the process of transferring the actual exposure pattern to the wafer, due to the influence of the etching process, the critical dimension of the pattern of the structure formed on the wafer has etching bias with the critical dimension of the target pattern, therefore, the etching bias compensation value corresponding to the test pattern is obtained according to the actual etching pattern and the actual exposure pattern, and the etching bias compensation model is established according to the actual etching bias compensation value.

[0120] Specifically, in the embodiment, the size difference between the actual exposure pattern and the actual etching pattern is obtained as the etching bias compensation value according to the actual etching pattern and the actual exposure pattern.

[0121] The etching bias compensation model acquisition module 506 is configured to establish the etching bias compensation model in combination with the optical characteristic parameter of the test pattern and the etching bias compensation value.

[0122] In the embodiment, the etching bias compensation model is established according to the optical characteristic parameter and the etching bias compensation value, the compensation strategy established based on the optical characteristic parameter can take the optical effect into account, which is beneficial to obtain a more accurate etching bias compensation model, thereby being beneficial to more accurate etching bias compensation.

[0123] Correspondingly, in the embodiment, the etching bias compensation model is established in combination with the image log slope of the test pattern and the etching bias compensation value.

[0124] The image log slope of the test pattern in the actual exposure process is obtained to be used as the consideration of the optical effect to establish the etching bias compensation model, which is beneficial to establish a more accurate etching bias compensation model, therefore, the etching bias compensation model is established in combination with the image log slope of the test pattern and the etching bias compensation value, which is beneficial to take the influence of the optical effect into account and establish a more accurate etching bias compensation model.

[0125] In the embodiment, the etching deviation compensation model is established by combining the image log slope of the test pattern and the etching deviation compensation value, including: performing function fitting on the multiple image log slopes and the etching deviation compensation values of the test pattern to obtain a function function of layout correction.

[0126] As known from the foregoing, the image log slope has an influence on the numerical value of the etching deviation compensation, therefore, the function function of layout correction obtained by performing function fitting on the multiple image log slopes and the etching deviation compensation values of the test pattern can represent the etching deviation compensation model considering the influence of the optical effect.

[0127] In the embodiment, the function fitting is performed on the multiple image log slopes and the etching deviation compensation values of the test pattern to obtain the function function of layout correction, including: setting a polynomial fitting function with the image log slope as the independent variable and the etching deviation compensation value as the dependent variable.

[0128] As an example, in the embodiment, the expression of the polynomial fitting function is: f(x)=Ax 3 +Bx 2 +Cx+D, where x is the image log slope, f(x) is the etching deviation compensation value, and A, B, C and D are the fitting coefficients of the polynomial fitting function.

[0129] In other embodiments, the polynomial fitting function can also be set to a higher-order polynomial or a lower-order polynomial.

[0130] In the embodiment, the fitting coefficients of the polynomial fitting function are obtained by fitting the polynomial fitting function according to the multiple image log slopes and the etching deviation compensation values of the test pattern, so as to obtain the polynomial fitting function as the function function of layout correction.

[0131] As an example, in the embodiment, the polynomial fitting function f(x)=Ax 2 +Bx 2 +Cx+D is used, and the fitting coefficients A, B, C and D of the polynomial fitting function are obtained by fitting the polynomial fitting function according to the multiple image log slopes and the etching deviation compensation values, so as to obtain the polynomial fitting function as the function function of layout correction.

[0132] As an example, in the embodiment, the test pattern in the multiple test patterns includes a metal layer isolation pattern, and the expression of the function function in the function function of layout correction obtained by fitting the polynomial fitting function according to the multiple image log slopes and the etching deviation compensation values of the test pattern includes: Wherein, x is the image logarithmic slope, f(x) is the etching deviation compensation value.

[0133] The embodiment of the present application also provides a device which can implement the optical proximity correction method provided by the embodiment of the present application by loading the optical proximity correction method in the form of a program. An optional hardware structure of the terminal device provided by the embodiment of the present application can be as shown in the figure, comprising at least one processor 01, at least one communication interface 02, at least one memory 03 and at least one communication bus 04. Figure 7

[0134] In the embodiment, the number of the processor 01, the communication interface 02, the memory 03 and the communication bus 04 is at least one, and the processor 01, the communication interface 02 and the memory 03 complete the communication with each other through the communication bus 04. The communication interface 02 can be the interface of the communication module for network communication, such as the interface of the GSM module. The processor 01 can be a central processing unit CPU, or a specific integrated circuit (Application Specific Integrated Circuit, ASIC), or one or more integrated circuits configured to implement the embodiment of the present application. The memory 03 can contain a high-speed RAM memory and can also include a non-volatile memory (non-volatile memory, NVM), such as at least one disk memory. The memory 03 stores one or more computer instructions, and the processor 01 executes the one or more computer instructions to implement the optical proximity correction method provided by the embodiment of the present application.

[0135] It should be noted that the terminal device described above can also include other devices (not shown) that can not be necessary for the disclosure of the embodiment of the present application. Since these other devices can not be necessary for understanding the disclosure of the embodiment of the present application, the embodiment of the present application does not introduce them one by one.

[0136] The embodiment of the present application also provides a storage medium, which stores one or more computer instructions, and the one or more computer instructions are used to implement the establishment method of the etching deviation compensation model provided by the embodiment of the present application.

[0137] In the establishment method of the etching deviation compensation model provided by the embodiment of the present application, the etching deviation compensation model is established in combination with the optical characteristic parameter of the test pattern and the etching deviation compensation value. In the embodiment of the present application, the etching deviation compensation model is established according to the optical characteristic parameter and the etching deviation compensation value. The compensation strategy established based on the optical characteristic parameter can take the optical effect into account, which is beneficial to obtain a more accurate etching deviation compensation model, thereby being beneficial to more accurate etching deviation compensation.

[0138] ​The above-described embodiments of the application are combinations of elements and features of the applications. The elements or features can be applied to one another only in combinations, unless otherwise indicated. Each individual element or feature can be replaced by alternative elements or features serving the same, equivalent or similar purpose, unless otherwise stated. The numerous individual features or elements of a specific embodiment are equally applicable in, and can be replaced with, alternative embodiments and equivalents thereof as set forth. Various modifications to these embodiments can be made by those skilled in the art, without departing from the spirit or scope of the application. Therefore, the scope of the application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0139] Embodiments of the present application can be implemented by various means, for example hardware, firmware, software, or a combination thereof. In a hardware configuration, the methods according to exemplary embodiments of the present application can be implemented by one or more Application Specific Integrated Circuits (ASICs), Digital Signal Processors (DSPs), Digital Signal Processing Devices (DSPDs), Programmable Logic Devices (PLDs), Field Programmable Gate Arrays (FPGAs), processors, controllers, micro-controllers, microprocessors, etc. In a firmware or software configuration, embodiments of the present application can be implemented in the form of modules, procedures, functions, etc. of doing tasks. Software code can be stored in a memory unit and executed by a processor. The memory unit is located at the interior or exterior of the processor and can transmit data to and receive data from the processor via various known means.

[0140] The above description of disclosed embodiments is merely intended to illustrate the general principles of the application. Various modifications can be made to the embodiments described in specific embodiments of the present application, as will be apparent to those skilled in the art. All such modifications will be within the scope of the present application as defined by the following claims, and their equivalents.

[0141] While the application has been disclosed in connection with the embodiments presented, it should be understood that modifications and / or improvements can be made to the above-described embodiments without departing from the spirit and scope of the application. Thus, the scope of the application should not be limited to the specific illustrative embodiments but rather should be given the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for establishing an etching deviation compensation model, characterized in that: include: Provide multiple test patterns; Performing actual exposure on the test pattern to obtain an actual exposure pattern; Obtaining optical characteristic parameters of the test pattern during actual exposure; Etching along the actual exposure pattern to obtain an actual etching pattern; Obtaining an etching deviation compensation value corresponding to the test pattern according to the actual etching pattern and the actual exposure pattern; The etching deviation compensation model is established by combining the optical characteristic parameters of the test pattern and the etching deviation compensation value.

2. The method for establishing an etching deviation compensation model according to claim 1, wherein: In obtaining the etching deviation compensation value corresponding to the test pattern according to the actual etching pattern and the actual exposure pattern, a size difference between the actual exposure pattern and the actual etching pattern is obtained as the etching deviation compensation value.

3. The method for establishing an etching deviation compensation model according to claim 1, wherein: Obtaining the optical characteristic parameters of the test pattern during the actual exposure process, and obtaining the image logarithmic slope of the test pattern during the actual exposure process; In establishing the etching deviation compensation model by combining the optical characteristic parameters of the test pattern and the etching deviation compensation value, the etching deviation compensation model is established by combining the image logarithmic slope of the test pattern and the etching deviation compensation value.

4. The method for establishing an etching deviation compensation model according to claim 3, wherein: The etching deviation compensation model is established in combination with the image logarithmic slope and etching deviation compensation value of the test pattern, including: performing function fitting on multiple image logarithmic slopes and etching deviation compensation values ​​of the test pattern to obtain a functional function of the etching deviation compensation model.

5. The method for establishing an etching deviation compensation model according to claim 4, wherein: Performing function fitting on a plurality of image logarithmic slopes and etching deviation compensation values ​​of the test pattern to obtain a functional function of the etching deviation compensation model, comprising: setting a polynomial fitting function with the image logarithmic slope as an independent variable and the etching deviation compensation value as a dependent variable; The polynomial fitting function is fitted according to multiple image logarithmic slopes and etching deviation compensation values ​​of the test pattern to obtain fitting coefficients of the polynomial fitting function, so as to obtain the polynomial fitting function as a functional function of the etching deviation compensation model.

6. The method for establishing an etching deviation compensation model according to claim 5, wherein: According to the multiple image logarithmic slopes of the test pattern and the etching deviation compensation value, the polynomial fitting function is fitted to obtain the fitting coefficient of the polynomial fitting function, so as to obtain the polynomial fitting function as the functional function of the etching deviation compensation model, wherein the expression of the functional function includes: Where x is the logarithmic slope of the image, and f(x) is the etching deviation compensation value.

7. The method for establishing an etching deviation compensation model according to claim 1 or 6, wherein: A plurality of test patterns are provided, wherein the test patterns include metal layer isolation patterns.

8. A layout correction method, characterized in that: include: Provide target graphics; Obtaining optical characteristic parameters of the target pattern under preset exposure conditions; According to the optical characteristic parameters, an etching deviation compensation value corresponding to the target pattern is obtained by using an etching deviation compensation model obtained by the method for establishing an etching deviation compensation model according to any one of claims 1 to 6; A layout pattern corresponding to the target pattern is obtained according to the etching deviation compensation value and the target pattern.

9. The layout correction method according to claim 8, wherein: The optical characteristic parameters of the target pattern under a preset exposure condition are obtained, where the optical characteristic includes an image logarithmic slope.

10. The layout correction method according to claim 8, wherein: Obtaining a layout pattern corresponding to the target pattern according to the etching deviation compensation value and the target pattern, including: taking the sum of the size of the target pattern and the etching deviation compensation value as the size of the layout pattern.

11. The layout correction method according to claim 8, wherein: In providing a target pattern, the target pattern includes a metal layer isolation pattern.

12. A system for establishing an etching deviation compensation model, characterized in that: include: A test pattern providing module is used to provide multiple test patterns; An actual exposure module, used for actually exposing the test pattern to obtain an actual exposure pattern; An optical characteristic parameter acquisition module, used to obtain the optical characteristic parameters of the test pattern during the actual exposure process; An actual etching module, configured to perform etching along the actual exposure pattern to obtain an actual etching pattern; an etching deviation compensation value acquisition module, configured to obtain an etching deviation compensation value corresponding to the test pattern according to the actual etching pattern and the actual exposure pattern; The etching deviation compensation model acquisition module is used to establish the etching deviation compensation model by combining the optical characteristic parameters of the test pattern and the etching deviation compensation value.

13. A device, characterized in that The method comprises at least one memory and at least one processor, wherein the memory stores one or more computer instructions, wherein the one or more computer instructions are executed by the processor to implement the method for establishing an etching deviation compensation model according to any one of claims 1 to 7.

14. A storage medium, characterized in that The storage medium stores one or more computer instructions, and the one or more computer instructions are used to implement the method for establishing an etching deviation compensation model according to any one of claims 1 to 7.

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