CN114077153A - Chip manufacturing method - Google Patents

Abstract

The embodiment of the application discloses a manufacturing method of a chip, which comprises the following steps: providing a photomask; dividing the first surface of the photomask into a plurality of preset areas with the same size and shape; acquiring the graph density of each preset area in the plurality of preset areas according to the number of preset graphs in each preset area; obtaining a correction area according to the graph density of the preset area, wherein the correction area comprises at least one preset area with the graph density value range between a first preset value and a second preset value, and the preset area comprises end point values; selecting a plurality of measuring points in the correction area, and adjusting the exposure dose when the photomask is used for manufacturing a chip according to the line widths of preset graphs at the positions of the measuring points; according to the adjusted exposure dose, the photomask is used for manufacturing the chip, the uniformity of the line width of the chip can be effectively improved, and the yield of the chip is improved.

Description

Chip manufacturing method

Technical Field

The application relates to the technical field of semiconductors, in particular to a manufacturing method of a chip.

Background

With the development of semiconductor technology and the demand of industrial production, the size of semiconductor devices is continuously reduced, and the reduction of the size of semiconductor devices inevitably leads to the continuous reduction of chip line width (CD).

However, the line width of the chip is continuously decreased, which increases the difficulty of controlling the line width of the chip when manufacturing the chip, and affects the line width uniformity (CDU) of the chip, resulting in poor line width uniformity of the chip, thereby affecting the yield of the chip. Therefore, in order to effectively avoid the influence of the uniformity of the line width of the chip on the yield of the chip, the chip manufacturing method capable of improving the uniformity of the line width of the chip is provided, which becomes a research focus of those skilled in the art.

Disclosure of Invention

In order to solve the above technical problem, embodiments of the present application provide a method for manufacturing a chip, which can help to improve uniformity of a line width, thereby helping to improve yield of the chip.

In order to solve the above problem, the embodiment of the present application provides the following technical solutions:

a method of fabricating a chip, the method comprising:

providing a photomask, wherein the first surface of the photomask is provided with a plurality of preset patterns;

dividing the first surface of the photomask into a plurality of preset areas with the same size and shape;

acquiring the graph density of each preset area in the plurality of preset areas according to the number of preset graphs in each preset area;

obtaining a correction area according to the graph density of each preset area in the plurality of preset areas, wherein the correction area comprises at least one preset area with the graph density value range between a first preset value and a second preset value, and the preset area comprises end point values;

selecting a plurality of measuring points in the correction area, wherein the measuring points are positioned on a preset graph in the correction area, and adjusting the exposure dose when the photomask is used for manufacturing a chip according to the line width of the preset graph at the positions of the measuring points;

and manufacturing a chip by using the photomask according to the adjusted exposure dose.

Optionally, obtaining the corrected area according to the pattern density of each preset area in the plurality of preset areas includes:

obtaining a graph density curve of the photomask according to the graph density of each preset area in the plurality of preset areas;

obtaining the first preset value and the second preset value according to the graph density curve;

and obtaining the correction area according to the first preset value and the second preset value.

Optionally, the correction area includes at least one preset area, and selecting a plurality of measurement points in the correction area includes:

selecting a plurality of measuring points in at least one preset area in the correction area;

wherein selecting a plurality of measurement points in at least one preset region in the correction region comprises:

selecting a plurality of measuring points in a first direction and a second direction of at least one preset area in the correction area respectively;

the first direction and the second direction are parallel to a first surface of the reticle, and the first direction is perpendicular to the second direction.

Optionally, the correction area includes a plurality of preset areas, and selecting a plurality of measurement points in the correction area includes:

selecting a plurality of measuring points in each preset area in the correction area;

wherein selecting a plurality of measurement points in each preset region in the correction region comprises:

selecting a plurality of measuring points in the first direction and the second direction of each preset area in the correction area;

the first direction and the second direction are parallel to a first surface of the reticle, and the first direction is perpendicular to the second direction.

Optionally, adjusting the exposure dose when the photomask is used to manufacture a chip according to the line width of the preset pattern at the position of the plurality of measurement points includes:

obtaining the line widths of the positions of the plurality of measuring points;

comparing the line widths of the preset patterns at the positions of the plurality of measuring points with the preset line width of the chip to obtain the difference value between the line widths of the preset patterns at the positions of the plurality of measuring points and the preset line width of the chip;

adjusting the exposure dose when the photomask is used for manufacturing a chip according to the difference value;

the preset line width of the chip is an ideal value of the line width of the chip.

Optionally, adjusting the exposure dose when the photomask is used to manufacture a chip according to the difference comprises:

when the difference value between the line width of the preset graph at the position of the measuring point and the preset line width of the chip is smaller than a third preset value, and the chip is manufactured by using the photomask, the exposure dose of the wafer of the chip corresponding to the position of the measuring point is increased;

when the difference value between the line width of the preset graph at the position of the measuring point and the preset line width of the chip is larger than a fourth preset value, reducing the exposure dose of the wafer of the chip corresponding to the position of the measuring point when the chip is manufactured by using the photomask;

and when the value range of the difference value between the line width of the preset graph at the position of the measuring point and the preset line width of the chip is between the third preset value and the fourth preset value, including an end point value, and when the chip is manufactured by using the photomask, the exposure dose of the wafer of the chip corresponding to the position of the measuring point is not changed.

Compared with the prior art, the technical scheme has the following advantages:

the technical scheme provided by the embodiment of the application comprises the following steps: providing a photomask, wherein the first surface of the photomask is provided with a plurality of preset patterns; dividing the first surface of the photomask into a plurality of preset areas with the same size and shape; acquiring the graph density of each preset area in the plurality of preset areas; obtaining a correction area according to the graph density of the preset area, wherein the correction area comprises at least one preset area with the graph density value range between a first preset value and a second preset value, and the preset area comprises end points; selecting a plurality of measuring points in the correction area, and adjusting the exposure dose when the photomask is used for manufacturing a chip according to the line width of a preset graph at the position of the measuring points; and manufacturing the chip by using the photomask according to the adjusted exposure dose. As can be seen from the above, the method provided in the embodiment of the present application obtains the corrected region according to the pattern densities of the plurality of preset regions on the first surface of the photomask, and selects the plurality of measurement points in the corrected region, knowing that the value range of the pattern density of the corrected region is between the first preset value and the second preset value, including the end point value, which can avoid the too large or too small pattern density of the corrected region, and further avoid the too large or too small line width of the positions of the plurality of measurement points selected in the corrected region, so that the line width of the positions of the selected measurement points can more truly reflect the actual line width distribution of the photomask, and thus when adjusting the exposure dose according to the line width of the positions of the measurement points, the exposure dose can be accurately adjusted, the uniformity of the line width of the manufactured chip is better according to the adjusted exposure dose, and the uniformity of the line width of the chip can be improved, thereby contributing to improving the yield of the chip.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a graph showing a relationship between a line width at a position of a measurement point on a predetermined pattern in a photomask and a density of the photomask pattern;

fig. 2 is a flowchart of a method for manufacturing a chip according to an embodiment of the present disclosure;

FIG. 3 is a top view of a mask in a method for fabricating a chip according to an embodiment of the present disclosure;

FIG. 4 is a comparison graph of line width distribution curves of chips manufactured by different chip manufacturing methods;

FIG. 5 is a mask pattern density profile in a method for fabricating a chip according to an embodiment of the present disclosure;

fig. 6 is a graph density distribution diagram of a plurality of predetermined regions of a mask in a method for manufacturing a chip according to an embodiment of the present disclosure.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application, but the present application may be practiced in other ways than those described herein, and it will be apparent to those of ordinary skill in the art that the present application is not limited to the specific embodiments disclosed below.

Next, the present application will be described in detail with reference to the drawings, and in the detailed description of the embodiments of the present application, the cross-sectional views illustrating the structure of the device are not enlarged partially according to the general scale for convenience of illustration, and the drawings are only examples, which should not limit the scope of the protection of the present application. In addition, the three-dimensional dimensions of length, width and depth should be included in the actual fabrication.

As described in the background section, in order to effectively avoid the influence of the line width uniformity of the chip on the yield of the chip, it is a research focus of those skilled in the art to provide a chip manufacturing method capable of improving the line width uniformity of the chip.

As the size of semiconductor devices is continuously reduced, the control of the line width uniformity of chips is becoming more and more important to ensure the yield of chips.

Under a normal condition, when a chip is manufactured, in order to improve the line width uniformity of the manufactured chip, a plurality of measuring points are generally selected on a photomask, the line widths of positions of the plurality of measuring points are obtained, the deviation between the line widths of the positions of the plurality of measuring points on the photomask and the ideal line width of the chip is obtained according to the line widths of the positions of the plurality of measuring points on the photomask and the ideal line width of the chip, a compensation value of an exposure dose when the chip is manufactured according to the photomask is obtained according to the deviation between the line widths of the positions of the plurality of measuring points on the photomask and the ideal line width of the chip, the exposure dose when the chip is manufactured is accurately adjusted as much as possible, and then a graph on the photomask is transferred onto a wafer according to the adjusted exposure dose to form the chip, so that the line width uniformity of the chip is improved.

In order to improve the line width uniformity of a chip, the line width of the chip is usually corrected by using the existing chip manufacturing method, which includes: providing a photomask, wherein the photomask is provided with a preset pattern; randomly selecting a plurality of measuring points on a photomask, generally randomly selecting 64-200 measuring points, obtaining the line widths of the positions of the plurality of measuring points, comparing the line widths of the positions of the plurality of measuring points with the ideal line width of a chip to obtain the deviation between the line widths of the positions of the plurality of measuring points on the photomask and the ideal line width of the chip, wherein the line widths of the positions of the plurality of measuring points on the photomask represent the average line width of a graph around the plurality of measuring points on the photomask, and then the average line width is used as a standard for measuring the line width distribution of the photomask, then obtaining the distribution of a compensation value of an exposure dose on the surface of a wafer which is to form the chip according to the deviation between the line widths of the positions of the plurality of measuring points on the photomask and the ideal line width of the chip, adjusting the exposure dose when the chip is manufactured by using the photomask according to the compensation value, and then adjusting the exposure dose according to the adjusted exposure dose, and transferring the preset pattern on the photomask to a wafer to form a chip by a photoetching process so as to improve the line width uniformity of the chip. It should be noted that, when a chip is manufactured, a preset pattern on the photomask needs to be transferred onto a wafer through a photolithography process, so that the preset pattern on the photomask corresponds to a pattern on the formed chip.

However, as can be seen from the above, the conventional chip fabrication method is random for selecting the measurement points on the mask. Generally, as shown in fig. 1, a mask surface has a plurality of predetermined patterns, and Pattern Densities (PDs) of different regions on the mask are different, so that line widths of regions with high Pattern Density are smaller, and line widths of regions with low Pattern Density are larger. The existing chip manufacturing method selects the measuring points on the photomask randomly, and does not consider the influence of the graph density on the line width of the position where the measuring point of the photomask is located, so that when the line width of the position where the measuring point of the photomask is located is obtained, if the selected measuring point is located in an area with high graph density, the line width of the position where the measuring point is located is small, if the selected measuring point is located in an area with low graph density, the line width of the position where the measuring point is located is large, the real line width distribution of the photomask cannot be reflected, the exposure dose cannot be correctly adjusted, the accuracy of the exposure dose when the graph on the photomask is transferred to a wafer to form a chip cannot be ensured, the line width uniformity of the chip is influenced, and the yield of the chip is further influenced.

Based on this, an embodiment of the present application provides a method for manufacturing a chip, as shown in fig. 2, the method includes the following steps:

s1: as shown in fig. 3, a mask 10 is provided, wherein a first surface of the mask 10 has a plurality of predetermined patterns 11;

s2: continuing with FIG. 3, the first surface of the mask 10 is divided into a plurality of predetermined areas 12 having the same size and shape;

s3: acquiring the pattern density of each preset area 12 in the plurality of preset areas 12 according to the number of the preset patterns 11 in each preset area 12 in the plurality of preset areas 12;

s4: obtaining a correction area 13 according to the pattern density of each preset area 12 in the plurality of preset areas 12, wherein the correction area 13 comprises at least one preset area 12 with a pattern density value range between a first preset value and a second preset value, and comprises end points;

s5: selecting a plurality of measuring points in the correction area 13, wherein the measuring points are positioned on a preset graph in the correction area, and adjusting the exposure dose when the photomask is used for manufacturing a chip according to the line width of the preset graph at the positions of the measuring points; it should be noted that the line width of the preset pattern at the position of the plurality of measurement points is the line width of the pattern line corresponding to the position of the measurement point on the preset pattern, and is not the line width of the whole preset pattern, nor the whole width of the preset pattern at the position of the measurement point.

S6: and manufacturing a chip by using the photomask according to the adjusted exposure dose.

It should be noted that the line width of the photomask has a crucial influence on the line width uniformity of the chip, and in order to improve the line width uniformity of the chip, a plurality of measurement points need to be selected from the photomask, the line widths of the preset patterns at the positions of the plurality of measurement points on the photomask are obtained, and the line width of the chip is corrected according to the line widths of the preset patterns at the positions of the plurality of measurement points on the photomask, so as to improve the line width uniformity of the chip. The line width of the preset graph at the position of the obtained measuring point of the photomask is related to the graph density of the area where the measuring point of the photomask is located, the larger the graph density is, the smaller the line width of the preset graph at the position of the measuring point of the photomask is, otherwise, the larger the line width of the preset graph at the position of the measuring point of the photomask is, so that if the graph density of the area where the selected measuring point is located is not moderate, the line width of the preset graph at the position of the measuring point cannot accurately reflect the line width of the photomask, and further, the exposure dose when the chip is manufactured by using the photomask cannot be accurately adjusted, and the chip manufactured by using the photomask can influence the line width uniformity of the chip.

In the embodiment of the application, the manufacturing method obtains the corrected area according to the pattern density of the plurality of preset areas on the first surface of the photomask, and selects the plurality of measurement points in the corrected area, knowing that the value range of the pattern density of the corrected area is between the first preset value and the second preset value, including the end point value, so that the pattern density of the corrected area can be prevented from being too large or too small, and further the line width of the preset pattern at the position of the plurality of measurement points selected in the corrected area can be prevented from being too large or too small, so that the line width of the preset pattern at the position of the selected measurement points can reflect the actual line width distribution of the photomask more truly, and therefore, when the exposure dose is adjusted according to the line width of the preset pattern at the position of the measurement points, the exposure dose can be accurately adjusted, and the uniformity of the line width of the manufactured chip is better according to the adjusted exposure dose, the method is beneficial to improving the line width uniformity of the chip, and further beneficial to improving the yield of the chip.

Specifically, as shown in fig. 4, fig. 4 is a comparison graph of chip line width distribution curves, in which a line 1 is a chip line width distribution curve manufactured by using the manufacturing method provided in the embodiment of the present application, a line 2 is a chip line width distribution curve manufactured by using the conventional chip manufacturing method, and a line 3 is a line width distribution curve of a chip manufactured by using a chip manufacturing method without adjusting an exposure dose, and it can be known from the line width distribution curves in fig. 4 that the line width distribution curve of the chip manufactured by using the method provided in the embodiment of the present application is the narrowest, the line width distribution curve of the chip manufactured by using the chip manufacturing method is the second order, and the line width distribution curve of the chip manufactured by using the chip manufacturing method without adjusting the exposure dose is the widest, so that the difference of the line widths of the chips manufactured by using the method provided in the embodiment of the present application is small, that is, the line width uniformity is the best, the method for manufacturing the chip can effectively improve the line width uniformity of the chip and is beneficial to improving the yield of the chip.

It should be noted that, in the embodiment of the present application, the surface of the photomask is scanned by a software program loaded on a certain hardware, the surface of the photomask is divided into a plurality of preset regions having the same size and shape, and the pattern density of the plurality of preset regions is obtained according to the number of preset patterns of each preset region, which is not described in detail herein.

On the basis of the foregoing embodiment, in an embodiment of the present application, obtaining the correction area according to the pattern density of each of the plurality of preset areas includes: obtaining a graph density curve of the photomask according to the graph density of each preset area in the plurality of preset areas; obtaining the first preset value and the second preset value according to the graph density curve of the photomask, obtaining the pattern density value with moderate pattern density on the first surface of the photomask according to the pattern density curve, wherein the first preset value is smaller than the second preset value, and in general, the first preset value and the second preset value are respectively located at two sides of the highest point of the graph density curve, and the difference between the figure density value corresponding to the first preset value and the figure density value corresponding to the highest point of the figure density curve is not more than 10 percent, the difference value between the graph density value corresponding to the second preset value and the graph density value corresponding to the highest point of the graph density curve is not more than 10 percent, thereby obtaining the first preset value and the second preset value according to the graph density curve of the photomask; the corrected area is obtained according to the first preset value and the second preset value, and the excessive or insufficient pattern density of the corrected area can be effectively prevented, so that the line width of the corrected area is prevented from being too small or too large, accurate adjustment of exposure dose when a chip is manufactured by using the photomask is facilitated, the line width uniformity of the chip can be effectively improved, and the yield of the chip is facilitated to be improved. It should be noted that, when determining the correction area on the photomask, the suitable value of the pattern density of the correction area is different according to the characteristics of the pattern on the chip produced by the chip factory, and needs to be determined according to the actual situation of the chip, but at present, it is generally considered that the area where the pattern density is between 10% smaller than the density value corresponding to the highest point of the pattern density curve and 10% larger than the density value corresponding to the highest point of the pattern density curve is suitable as the correction area, but the present application does not limit this area, and is determined according to the situation.

Specifically, as shown in fig. 5, fig. 5 is a graph density distribution curve of the first surface of the photomask in the method provided by the embodiment of the present application, in which an abscissa is a graph density, an ordinate is a number of preset regions corresponding to each graph density, a value of the graph density corresponding to a is a first preset value, a value of the graph density corresponding to B is a second preset value, a preset region where the graph density is smaller than the first preset value is a region where the graph density is too small, a preset region where the graph density is greater than the second preset value is a region where the graph density is too large, a preset region where the graph density is between the first preset value and the second preset value is a region where the graph density is moderate, including end points, that is, a correction region, the region where the graph density is too large and the graph density is too small can be excluded by the graph density distribution curve, and a measurement point is selected only in the correction region where the graph density is moderate, the line width of the selected measuring point can truly reflect the line width distribution of the photomask, so that the line width uniformity of the chip manufactured by the manufacturing method is improved, and the yield of the chip is improved.

As shown in fig. 6, the area C in fig. 6 is a correction area where the value range of the pattern density is between a first preset value and a second preset value, and the area D and the area E are respectively a preset area where the pattern density is smaller than the first preset value and a preset area where the pattern density is greater than the second preset value. When the line width of the chip is corrected, measuring points are selected in a correction area with the value range of the graph density between a first preset value and a second preset value, the measuring points cannot be selected in a preset area D with the graph density smaller than the first preset value and a preset area E with the graph density larger than the second preset value, and the line width of the position where the measuring points are located is prevented from being influenced by the graph density of the area where the selected measuring points are located. It should be noted that, in other embodiments of the present application, a value range of the pattern density of the correction area may also be other values, which is not limited in the present application and is determined as the case may be.

On the basis of the above embodiment, in an embodiment of the present application, selecting a plurality of measurement points in the correction area includes: selecting a plurality of measuring points in at least one preset area in the correction area; wherein selecting a plurality of measurement points in at least one preset region in the correction region comprises: the method comprises the steps of selecting a plurality of measuring points in a first direction and a second direction of at least one preset area in the correction area respectively, enabling the first direction and the second direction to be parallel to the first side surface of the photomask, enabling the first direction to be perpendicular to the second direction, enabling the selected measuring points to be capable of responding to the line width distribution of the photomask as diverse as possible, enabling the selected measuring points in the at least one preset area in the correction area to be capable of responding to the line width distribution of the photomask as possible, facilitating adjustment of exposure dose when the photomask is used for manufacturing a chip, improving the line width uniformity of the chip, and improving the yield of the chip.

In another embodiment of the present application, the correction area includes a plurality of preset areas, and selecting a plurality of measurement points in the correction area includes: selecting a plurality of measuring points in each preset area in the correction area; wherein selecting a plurality of measurement points in each preset region in the correction region comprises: the method comprises the steps of selecting a plurality of measuring points in a first direction and a second direction of each preset area in the correction area respectively, wherein the first direction and the second direction are parallel to the first side surface of the photomask, and the first direction is perpendicular to the second direction, so that the selected measuring points can reflect the line width distribution of the photomask as diverse as possible, the selected measuring points in at least one preset area in the correction area can reflect the line width distribution of the photomask as possible, the exposure dose when a chip is manufactured by using the photomask can be adjusted, the line width uniformity of the chip is improved, and the yield of the chip is improved. It should be noted that, when the correction area includes a plurality of preset areas and a plurality of measurement points are selected in the correction area, a plurality of measurement points may also be selected in at least one preset area of the plurality of preset areas of the correction area, which is not limited in this application and is determined as the case may be.

On the basis of any of the above embodiments, in an embodiment of the present application, adjusting an exposure dose when a chip is manufactured by using the photomask according to a line width of a preset pattern at a position where the plurality of measurement points are located includes: selecting a plurality of measuring points in the correction area, and obtaining the line widths of preset graphs at the positions of the measuring points; comparing the line widths of the preset patterns at the positions of the plurality of measuring points with the preset line width of the chip according to the line widths of the preset patterns at the positions of the plurality of measuring points to obtain a difference value between the line widths of the preset patterns at the positions of the plurality of measuring points and the preset line width of the chip, wherein the preset line width of the chip is an ideal value of the line width of the chip; and according to the difference value, namely the difference value between the line width of the preset graph at the position of the plurality of measuring points and the preset line width of the chip, obtaining the distribution of the compensation value of the exposure dose on the surface of the wafer when the photomask is used for manufacturing the chip, so as to adjust the exposure dose when the photomask is used for manufacturing the chip. Because the exposure dose has an important influence on the line width when the preset pattern on the photomask is transferred to the wafer to manufacture the chip, the method can correctly adjust the exposure dose when the photomask is used for manufacturing the chip by utilizing the difference value between the line width of the preset pattern at the positions of the plurality of measuring points and the preset line width of the chip, and is beneficial to improving the line width uniformity of the chip manufactured by the manufacturing method, thereby being beneficial to improving the line width uniformity of the chip and improving the yield of the chip.

On the basis of the foregoing embodiments, in an embodiment of the present application, for an embodiment in which a plurality of measurement points are selected from at least one of the preset regions in the correction region, or for an embodiment in which a plurality of measurement points are selected from each of the preset regions in the correction region, adjusting an exposure dose when a chip is manufactured by using the photomask according to the difference, that is, the difference between the line width of the position where the plurality of measurement points are located and the preset line width of the chip, includes: when the difference value between the line width of the preset pattern at the position of the measuring point and the preset line width of the chip is smaller than a third preset value, namely the preset line width of the chip is larger than the line width of the preset pattern at the position of the measuring point, and the difference value between the line width of the preset pattern at the position of the measuring point and the preset line width of the chip exceeds an allowable range, in order to improve the uniformity of the line width of the chip when the pattern on the photomask is transferred to the wafer to form the chip, when the photomask is used for manufacturing the chip, the exposure dose of the wafer at the position corresponding to the measuring point is increased, namely the compensation value of the exposure dose of the wafer at the position corresponding to the measuring point is larger than 0;

when the difference value between the line width of the preset pattern at the position of the measuring point and the preset line width of the chip is larger than a fourth preset value, namely the preset line width of the chip is smaller than the line width of the preset pattern at the position of the measuring point, and the difference value between the line width of the preset pattern at the position of the measuring point and the preset line width of the chip exceeds an allowable range, in order to transfer the pattern on the photomask to the wafer to form the chip, the uniformity of the line width of the chip is improved, when the chip is manufactured by using the photomask, the exposure dose of the chip wafer at the position corresponding to the position of the measuring point is reduced, namely the compensation value of the exposure dose at the position corresponding to the position of the measuring point is smaller than 0;

when the difference value between the line width of the preset pattern at the position of the measuring point and the preset line width of the chip is between the third preset value and the fourth preset value, the difference value includes an endpoint value, namely, the difference value between the line width of the preset pattern at the position of the measuring point and the preset line width of the chip is within an allowable range, when the chip is manufactured by using the photomask, the exposure dose of the wafer of the chip and the position corresponding to the position of the measuring point is not changed, namely, the compensation value of the exposure dose is equal to 0, and the exposure dose is not changed.

It should be noted that, when the photomask is used to manufacture the chip, the pattern of the photomask is transferred onto the chip through a photolithography process, the preset pattern on the photomask corresponds to the formed pattern on the chip, and the line width of the preset pattern at the position of the measurement point represents the line width of the peripheral region of the measurement point, so that the exposure dose of the peripheral region of the chip wafer corresponding to the position of the measurement point can be represented according to the exposure dose adjusted by the line width of the preset pattern at the position of the measurement point, thereby adjusting the exposure dose when manufacturing the chip. And when the graph on the photomask is transferred to a wafer to form a chip, the graph on the photomask needs to be projected onto the wafer, so that when the photomask is used for manufacturing the chip, the exposure dose of the position corresponding to the position of the measuring point on the photomask on the chip wafer is changed, the exposure dose during manufacturing the chip can be adjusted, the line width of the upper shape of the chip is adjusted, and the line width uniformity of the chip is improved. It should be further noted that, in the embodiment of the present application, specific values of the third preset value and the fourth preset value are not limited, and are related to the requirement of manufacturing accuracy of a chip, as the case may be.

In summary, an embodiment of the present application provides a method for manufacturing a chip, including: providing a photomask, wherein the first surface of the photomask is provided with a plurality of preset patterns; dividing the first surface of the photomask into a plurality of preset areas with the same size and shape; acquiring the graph density of each preset area in the plurality of preset areas; obtaining a correction area according to the graph density of the preset area, wherein the correction area comprises at least one preset area with the graph density value range between a first preset value and a second preset value, and the preset area comprises end points; selecting a plurality of measuring points in the correction area, and adjusting the exposure dose when the photomask is used for manufacturing a chip according to the line width of a preset graph at the position of the measuring points; and manufacturing the chip by using the photomask according to the adjusted exposure dose. As can be seen from the above, the method provided in the embodiment of the present application obtains the corrected region according to the pattern densities of the plurality of preset regions on the first surface of the photomask, and selects the plurality of measurement points in the corrected region, knowing that the value range of the pattern density of the corrected region is between the first preset value and the second preset value, including the end point value, which can avoid the too large or too small pattern density of the corrected region, and further avoid the too large or too small line width of the positions of the plurality of measurement points selected in the corrected region, so that the line width of the positions of the selected measurement points can more truly reflect the actual line width distribution of the photomask, and thus when adjusting the exposure dose according to the line width of the positions of the measurement points, the exposure dose can be accurately adjusted, the uniformity of the line width of the manufactured chip is better according to the adjusted exposure dose, and the uniformity of the line width of the chip can be improved, thereby contributing to improving the yield of the chip.

All parts in the specification are described in a mode of combining parallel and progressive, each part is mainly described to be different from other parts, and the same and similar parts among all parts can be referred to each other.

In the above description of the disclosed embodiments, features described in various embodiments in this specification can be substituted for or combined with each other to enable those skilled in the art to make or use the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present 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.

Claims (6)

1. A method for manufacturing a chip, comprising:

providing a photomask, wherein the first surface of the photomask is provided with a plurality of preset patterns;

dividing the first surface of the photomask into a plurality of preset areas with the same size and shape;

acquiring the graph density of each preset area in the plurality of preset areas according to the number of preset graphs in each preset area;

obtaining a correction area according to the graph density of each preset area in the plurality of preset areas, wherein the correction area comprises at least one preset area with the graph density value range between a first preset value and a second preset value, and the preset area comprises end point values;

selecting a plurality of measuring points in the correction area, wherein the measuring points are positioned on a preset graph in the correction area, and adjusting the exposure dose when the photomask is used for manufacturing a chip according to the line width of the preset graph at the positions of the measuring points;

and manufacturing a chip by using the photomask according to the adjusted exposure dose.

2. The method of claim 1, wherein obtaining the corrected region according to the pattern density of each of the plurality of predetermined regions comprises:

obtaining a graph density curve of the photomask according to the graph density of each preset area in the plurality of preset areas;

obtaining the first preset value and the second preset value according to the graph density curve;

and obtaining the correction area according to the first preset value and the second preset value.

3. The method of claim 1, wherein the modified region comprises at least one preset region, and wherein selecting a plurality of measurement points in the modified region comprises:

selecting a plurality of measuring points in at least one preset area in the correction area;

wherein selecting a plurality of measurement points in at least one preset region in the correction region comprises:

selecting a plurality of measuring points in a first direction and a second direction of at least one preset area in the correction area respectively;

the first direction and the second direction are parallel to a first surface of the reticle, and the first direction is perpendicular to the second direction.

4. The method of claim 1, wherein the modified region comprises a plurality of preset regions, and wherein selecting a plurality of measurement points in the modified region comprises:

selecting a plurality of measuring points in each preset area in the correction area;

wherein selecting a plurality of measurement points in each preset region in the correction region comprises:

selecting a plurality of measuring points in the first direction and the second direction of each preset area in the correction area;

the first direction and the second direction are parallel to a first surface of the reticle, and the first direction is perpendicular to the second direction.

5. The method of claim 1, wherein adjusting the exposure dose for fabricating the chip using the mask according to the line width of the predetermined pattern at the position of the measurement points comprises:

obtaining the line widths of the positions of the plurality of measuring points;

comparing the line widths of the preset patterns at the positions of the plurality of measuring points with the preset line width of the chip to obtain the difference value between the line widths of the preset patterns at the positions of the plurality of measuring points and the preset line width of the chip;

adjusting the exposure dose when the photomask is used for manufacturing a chip according to the difference value;

the preset line width of the chip is an ideal value of the line width of the chip.

6. The method of claim 5, wherein adjusting the exposure dose for fabricating the chip using the reticle according to the difference comprises:

when the difference value between the line width of the preset graph at the position of the measuring point and the preset line width of the chip is smaller than a third preset value, and the chip is manufactured by using the photomask, the exposure dose of the wafer of the chip corresponding to the position of the measuring point is increased;

when the difference value between the line width of the preset graph at the position of the measuring point and the preset line width of the chip is larger than a fourth preset value, reducing the exposure dose of the wafer of the chip corresponding to the position of the measuring point when the chip is manufactured by using the photomask;

and when the value range of the difference value between the line width of the preset graph at the position of the measuring point and the preset line width of the chip is between the third preset value and the fourth preset value, including an end point value, and when the chip is manufactured by using the photomask, the exposure dose of the wafer of the chip corresponding to the position of the measuring point is not changed.

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