阅读说明：本技术 一种光罩的缺陷修复方法及光罩 (Photomask defect repairing method and photomask ) 是由 林大伟 张健澄 吴苇 于 2018-07-16 设计创作，主要内容包括：本发明提供一种光罩的缺陷修复方法及光罩,所述方法包括：提供待修复光罩,所述待修复光罩包括遮光层以及形成在所述遮光层中的透光图案,所述透光图案包括具有缺陷的待修复图案；在所述待修复图案的外侧形成透光的若干散射条,以对所述待修复图案进行光补偿。本发明的方法过程更加容易控制,降低产生二次损伤缺陷的风险,可以提高修复合格率,降低修复循环次数。(The invention provides a photomask defect repairing method and a photomask, wherein the method comprises the following steps: providing a photomask to be repaired, wherein the photomask to be repaired comprises a light shielding layer and a light transmitting pattern formed in the light shielding layer, and the light transmitting pattern comprises a pattern to be repaired with defects; and forming a plurality of light-transmitting scattering strips on the outer side of the pattern to be repaired so as to perform light compensation on the pattern to be repaired. The method disclosed by the invention has the advantages that the process is easier to control, the risk of generating secondary damage defects is reduced, the repair qualification rate can be improved, and the repair cycle number is reduced.)

1. A method for repairing a defect of a photomask, comprising:

providing a photomask to be repaired, wherein the photomask to be repaired comprises a light shielding layer and a light transmitting pattern formed in the light shielding layer, and the light transmitting pattern comprises a pattern to be repaired with defects;

and forming a plurality of light-transmitting scattering strips on the outer side of the pattern to be repaired so as to perform light compensation on the pattern to be repaired.

2. The defect repair method of claim 1, wherein regions between the scattering bars and adjacent sides of the pattern to be repaired are opaque.

3. The defect repairing method according to claim 1, wherein at least one scattering bar is disposed outside each side of the pattern to be repaired, wherein the scattering bars are disposed in parallel with the corresponding sides of the pattern to be repaired.

4. The defect repairing method according to claim 3, wherein the pattern to be repaired is square, and one scattering bar is disposed outside each side of the pattern to be repaired.

5. The defect repairing method according to claim 1, wherein the scattering bars are disposed outside each corner of the pattern to be repaired, wherein each of the scattering bars comprises a first sub-scattering bar and a second sub-scattering bar which are respectively opposite to and parallel to different sides of the pattern to be repaired.

6. The defect repair method of claim 5, wherein the scattering bars have a zigzag shape in which one end point of the first sub-scattering bar is connected to one end point of the second sub-scattering bar.

7. The defect repair method of claim 1, wherein the reticle is used to transfer a pattern to a substrate using an exposure unit, wherein the pattern of the scattering bars is not transferred to the substrate.

8. The method for repairing defects of claim 1, wherein the mask to be repaired comprises a light-transmitting substrate and a light-shielding layer covering the light-transmitting substrate, and the defects are surface damages of a part of the light-transmitting substrate in the pattern to be repaired.

9. The defect repair method of claim 8, wherein the light-transmitting substrate is a quartz substrate, and the defects include quartz damage defects.

10. The defect repair method of claim 1, wherein forming the plurality of light-transmissive scattering bars comprises:

and etching the area of the light shielding layer, which is scheduled to form the scattering strip, so as to form an opening exposing the light-transmitting substrate of the photomask, wherein the opening is used as the scattering strip.

11. A photomask, comprising:

the light-transmitting pattern comprises a light-shielding layer and a light-transmitting pattern formed in the light-shielding layer, wherein the light-transmitting pattern comprises a pattern to be repaired with defects;

and forming a plurality of light-transmitting scattering strips on the outer side of the pattern to be repaired so as to perform optical compensation on the pattern to be repaired.

12. The mask of claim 11, wherein regions between the scattering bars and adjacent sides of the pattern to be repaired are opaque.

13. The mask of claim 11, wherein at least one scattering bar is disposed outside each side of the pattern to be repaired, wherein the scattering bars are disposed parallel to the corresponding sides of the pattern to be repaired.

14. The mask of claim 13, wherein the pattern to be repaired is square, and one scattering bar is disposed outside each side of the pattern to be repaired.

15. The mask of claim 11, wherein the scattering bars are disposed outside each corner of the pattern to be repaired, wherein each scattering bar comprises a first sub-scattering bar and a second sub-scattering bar opposite to and parallel to different sides of the pattern to be repaired, respectively.

16. The mask of claim 15, wherein the scattering bars are zigzag-shaped, and wherein an end of the first sub-scattering bar is connected to an end of the second sub-scattering bar.

17. The reticle of claim 11, wherein the reticle is for transferring a pattern to a substrate using an exposure unit, wherein the pattern of scattering bars is not transferred to the substrate.

18. The mask of claim 11, wherein the mask to be repaired comprises a light-transmitting substrate and a light-shielding layer covering the light-transmitting substrate, and the defect is a surface damage of a portion of the light-transmitting substrate in the pattern to be repaired.

19. The reticle of claim 18, wherein the light transmissive substrate is a quartz substrate and the defects comprise quartz damage defects.

Technical Field

The invention relates to the technical field of semiconductors, in particular to a photomask defect repairing method and a photomask.

Background

In the manufacturing process of a semiconductor integrated circuit, a Mask (Mask) is used to define the position of a circuit pattern, and then the projected circuit pattern is subjected to photolithography by a photolithography machine to form a desired device on a semiconductor substrate, that is, a pattern on the Mask is transferred to the semiconductor substrate by an exposure unit.

However, the mask preparation process is prone to introduce defects into the formed mask, which cause errors in the pattern of the mask, and thus the defects on the mask need to be repaired to reduce the pattern errors in the mask and obtain a mask meeting the design requirements. At present, two repairing methods are usually adopted for repairing, one is to etch a part of opaque defects (opaque defects) so as to make the repaired graph conform to the design, as shown in fig. 2A; another method is to repair by depositing a light-shielding layer on the partially transparent defect (clear defect) to make the repaired pattern conform to the design, as shown in fig. 2B. During reticle repair, a method of etching the edge of a light-transmitting pattern having quartz damage is generally used to repair quartz damage (quartz dammage), but as technology nodes improve, a repair method of etching the edge of a light-transmitting pattern (e.g., the light-transmitting pattern corresponds to a contact hole (contact) pattern intended to be formed on a substrate) has a high risk of generating secondary quartz defects, and when the repaired reticle is inspected by an aerial Image Measurement system (Aims), it is found that the improvement of Aims test results after repair is insignificant, thereby failing in repair. With the continuing improvement of technology nodes, the need for repair control becomes more challenging, and if quartz damage covers the entire transparent pattern (cleargraph), it becomes more and more difficult to etch the edges of the transparent pattern.

In view of the above problems, it is desirable to provide a novel method for repairing defects of a photomask and a photomask.

Disclosure of Invention

In this summary, concepts in a simplified form are introduced that are further described in the detailed description. This summary of the invention is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

In view of the existing problems, an aspect of the present invention provides a method for repairing defects of a mask, including:

providing a photomask to be repaired, wherein the photomask to be repaired comprises a light shielding layer and a light transmitting pattern formed in the light shielding layer, and the light transmitting pattern comprises a pattern to be repaired with defects;

and forming a plurality of light-transmitting scattering strips on the outer side of the pattern to be repaired so as to perform light compensation on the pattern to be repaired.

Illustratively, the scattering bars are opaque to light in the area between the side edges of the adjacent pattern to be repaired.

Illustratively, at least one scattering strip is respectively arranged outside each side edge of the pattern to be repaired, wherein the scattering strips are arranged in parallel with the corresponding side edges of the pattern to be repaired.

Illustratively, the shape of the pattern to be repaired is square, and one scattering strip is arranged outside each side edge of the pattern to be repaired respectively.

Illustratively, the scattering bars are arranged at the outer side of each corner of the pattern to be repaired, wherein each scattering bar comprises a first sub-scattering bar and a second sub-scattering bar which are respectively opposite to and parallel to different sides of the pattern to be repaired.

Illustratively, the scattering bars are in a zigzag shape, wherein an end point of the first sub-scattering bar is connected with an end point of the second sub-scattering bar.

Illustratively, the reticle is used to transfer a pattern to a substrate using an exposure unit, wherein the pattern of scattering bars is not transferred to the substrate.

Illustratively, the photomask to be repaired comprises a light-transmitting substrate and a light-shielding layer covering the light-transmitting substrate, and the defect is a surface damage of a part of the light-transmitting substrate in the pattern to be repaired.

Illustratively, the light-transmitting substrate is a quartz substrate, and the defects include quartz damage defects.

Illustratively, the method of forming the light-transmissive plurality of scattering bars includes:

and etching the area of the light shielding layer, which is scheduled to form the scattering strip, so as to form an opening exposing the light-transmitting substrate of the photomask, wherein the opening is used as the scattering strip.

Another aspect of the present invention provides a photomask, comprising:

the light-transmitting pattern comprises a light-shielding layer and a light-transmitting pattern formed in the light-shielding layer, wherein the light-transmitting pattern comprises a pattern to be repaired with defects;

and forming a plurality of light-transmitting scattering strips on the outer side of the pattern to be repaired so as to perform optical compensation on the pattern to be repaired.

Illustratively, the scattering bars are opaque to light in the area between the side edges of the adjacent pattern to be repaired.

Illustratively, at least one scattering strip is respectively arranged outside each side edge of the pattern to be repaired, wherein the scattering strips are arranged in parallel with the corresponding side edges of the pattern to be repaired.

Illustratively, the shape of the pattern to be repaired is square, and one scattering strip is arranged outside each side edge of the pattern to be repaired respectively.

Illustratively, the scattering bars are arranged at the outer side of each corner of the pattern to be repaired, wherein each scattering bar comprises a first sub-scattering bar and a second sub-scattering bar which are respectively opposite to and parallel to different sides of the pattern to be repaired.

Illustratively, the scattering bars are in a zigzag shape, wherein an end point of the first sub-scattering bar is connected with an end point of the second sub-scattering bar.

Illustratively, the reticle is used to transfer a pattern to a substrate using an exposure unit, wherein the pattern of scattering bars is not transferred to the substrate.

Illustratively, the photomask to be repaired comprises a light-transmitting substrate and a light-shielding layer covering the light-transmitting substrate, and the defect is a surface damage of a part of the light-transmitting substrate in the pattern to be repaired.

Illustratively, the light-transmitting substrate is a quartz substrate, and the defects include quartz damage defects.

According to the photomask defect repairing method and the photomask, the light-transmitting scattering strips are formed on the outer side of the pattern to be repaired to perform light compensation on the pattern to be repaired, so that the photomask with defects is repaired, the photomask meeting the design requirements is obtained, the process of the method is easier to control, the risk of generating secondary damage defects (such as quartz damage) is reduced, the repairing qualified rate can be improved, and the repairing cycle number is reduced.

Drawings

The following drawings of the invention are included to provide a further understanding of the invention. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

In the drawings:

FIG. 1 is a flow chart of a conventional photomask manufacturing process;

FIG. 2A is a schematic diagram illustrating defect repair by etching in a conventional repair method;

FIG. 2B shows a schematic diagram of defect repair by deposition in a conventional repair method;

FIG. 3 is a diagram illustrating a comparison of a normal pattern, a defect pattern, and a repair method pattern in one example;

FIG. 4 is a schematic diagram showing comparison of test results after repairing defects by etching in the conventional method;

FIG. 5A is a diagram illustrating a graph obtained by a defect repair method in an example of the invention;

FIG. 5B is a diagram illustrating a pattern obtained by a defect repair method according to another example of the present invention;

FIG. 6 is a graph showing a comparison of test results before and after repair according to the defect repair method of the present invention;

FIG. 7 is a schematic diagram showing the result of a repeatability test after the defect is repaired according to the defect repairing method of the present invention;

FIG. 8 is a flow chart illustrating a method for repairing defects in a reticle according to an embodiment of the present invention.

Detailed Description

In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention. It will be apparent, however, to one skilled in the art, that the present invention may be practiced without one or more of these specific details. In other instances, well-known features have not been described in order to avoid obscuring the invention.

It is to be understood that the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. In the drawings, the size and relative sizes of layers and regions may be exaggerated for clarity. Like reference numerals refer to like elements throughout.

It will be understood that when an element or layer is referred to as being "on," "adjacent to," "connected to," or "coupled to" other elements or layers, it can be directly on, adjacent to, connected or coupled to the other elements or layers or intervening elements or layers may be present. In contrast, when an element is referred to as being "directly on," "directly adjacent to," "directly connected to" or "directly coupled to" other elements or layers, there are no intervening elements or layers present. It will be understood that, although the terms first, second, third, etc. may be used to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the present invention.

Spatial relational terms such as "under," "below," "under," "above," "over," and the like may be used herein for convenience in describing the relationship of one element or feature to another element or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, then elements or features described as "below" or "beneath" other elements or features would then be oriented "above" the other elements or features. Thus, the exemplary terms "under" and "under" can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatial descriptors used herein interpreted accordingly.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. As used herein, the term "and/or" includes any and all combinations of the associated listed items.

Embodiments of the invention are described herein with reference to cross-sectional illustrations that are schematic illustrations of idealized embodiments (and intermediate structures) of the invention. As such, variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and/or tolerances, are to be expected. Thus, embodiments of the invention should not be limited to the particular shapes of regions illustrated herein but are to include deviations in shapes that result, for example, from manufacturing. For example, an implanted region shown as a rectangle will typically have rounded or curved features and/or implant concentration gradients at its edges rather than a binary change from implanted to non-implanted region. Also, a buried region formed by implantation may result in some implantation in the region between the buried region and the surface through which the implantation is performed. Thus, the regions illustrated in the figures are schematic in nature and their shapes are not intended to illustrate the actual shape of a region of a device and are not intended to limit the scope of the present invention.

In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present invention. The following detailed description of the preferred embodiments of the invention, however, the invention is capable of other embodiments in addition to those detailed.

Currently, the method for forming a mask generally includes the following processes: as shown in fig. 1, first, data preparation is performed, for example, size data of a circuit pattern to be formed is prepared, then, a light shielding layer (for example, chromium metal) and a photosensitive resist are sequentially formed on a substrate (for example, quartz glass), the designed circuit pattern is exposed on the photosensitive resist by an electronic laser device, the light shielding layer is etched using the photosensitive resist as a mask to form the circuit pattern, and then, processes of registration (registration), critical dimension Measurement (CD Measurement), Defect detection (Defect Inspection), Defect repair, cleaning and mounting, Particle Inspection (Particle Inspection), formation of a photo-masking film (Thr-Pellicle), final Inspection and & packaging, and final Shipping (Shipping) are further included, and the preparation of the photo-mask is realized through the above steps.

The defects in the photomask to be repaired are generally repaired by a pattern comparison method. The repairing method comprises the following steps: firstly, obtaining an SEM image of a normal photomask (a photomask without defects) or other normal areas in the photomask to be repaired, and taking the SEM image as a reference image; then, scanning the photomask to be repaired by adopting a scanning machine table to obtain an SEM image of the photomask to be repaired; then, comparing the reference pattern with the SEM pattern of the photomask to be repaired to determine the position of the defect in the photomask to be repaired, and further determining the position to be repaired; and finally, repairing the defects in the photomask to be repaired.

As shown in fig. 3, in which the left side is a normal pattern (normal pattern), i.e., a pattern without defects, the middle pattern is a defect pattern (damage pattern), e.g., a defect pattern with quartz damage defects, as shown in the right side of fig. 3, during reticle repair, a method of etching the edge of a transparent pattern with quartz damage is generally used to repair quartz damage (quartz damage), and the black lines in the figure indicate the etched area, but as the technology node improves, the repair method of etching the edge of a transparent pattern has a high risk of generating secondary quartz defects, as shown in fig. 4, when the reticle after repair is inspected by an aerial Image Measurement system (Aims) (atomic Measurement system), the left side of fig. 4 shows the test result before repair, the right side shows the test result after repair, and the improvement of the Aims test result after repair is found to be insignificant, the test result after repair still does not meet the design requirement, so that the repair fails. As technology nodes improve, the need for repair control turns out to be more challenging, and if quartz damage covers the entire transparent pattern (clearplate), it becomes increasingly difficult to etch the edges of the transparent pattern.

Therefore, in view of the above problems, the present invention provides a method for repairing defects of a mask, as shown in fig. 8, which mainly comprises the following steps:

step S1, providing a to-be-repaired photomask, where the to-be-repaired photomask includes a light-shielding layer and a light-transmitting pattern formed in the light-shielding layer, and the light-transmitting pattern includes a to-be-repaired pattern having a defect;

step S2, forming a plurality of light-transmitting scattering bars on the outer side of the pattern to be repaired, so as to perform optical compensation on the pattern to be repaired.

According to the photomask defect repairing method and the photomask, the light effect of the local area is changed by forming the scattering pattern on the shading layer adjacent to the defect, so that the light compensation of the pattern to be repaired is realized, the photomask with the defect is repaired, the photomask meeting the design requirement is obtained, the method process is easier to control, the small-sized challenging defect can be remedied, the method cannot damage the normal pattern on the photomask, the repairing qualified rate can be improved, and the repairing cycle number can be reduced.

The method for repairing defects of a reticle according to the present invention will be described in detail with reference to fig. 5A and 5B.

Illustratively, the method for repairing the defects of the photomask comprises the following steps:

first, step one is executed, as shown in fig. 5A and 5B, providing a to-be-repaired photomask, where the to-be-repaired photomask includes a light-shielding layer and a light-transmitting pattern formed in the light-shielding layer, and the light-transmitting pattern includes a to-be-repaired pattern 101 having a defect 102.

In one example, the photomask to be repaired comprises a light-transmitting substrate and a light-shielding layer covering the light-transmitting substrate.

Wherein the light-transmissive substrate may be any suitable light-transmissive substrate, including but not limited to a quartz substrate. The light shielding layer may be made of any suitable material having light shielding function, such as a metal material including, but not limited to, chromium (Cr), and, for example, an oxide (not shown), such as chromium oxide, may be selectively formed on the surface of the light shielding layer.

In particular, the preparation of the resulting reticle may be accomplished by any suitable method known to those skilled in the art, and in one example, the method of preparing the reticle includes: providing a light-transmitting substrate, such as fused quartz, forming a light shielding layer, such as a chromium layer, on the surface of the light-transmitting substrate, and spin-coating an electron beam photoresist on the light shielding layer; thereafter, a predetermined formed reticle pattern is transferred to the e-beam resist layer using an e-beam (or laser) direct write technique. The electron source generates a plurality of electrons which are accelerated, focused, shaped and projected on the electron beam photoresist, and scanned to form a required pattern; exposing and developing, and etching by a wet method or a dry method to remove part of the shading layer to expose the light-transmitting substrate so as to form a light-transmitting pattern; and removing the electron beam photoresist.

The mask preparation process is easy to introduce defects into the formed mask, which cause pattern errors in the mask, such as quartz damage, the existence of which affects the light transmittance and the imaging quality of the transparent pattern on the substrate, so that the defects on the mask need to be repaired to reduce the pattern errors in the mask and obtain a mask meeting the design requirements.

In the embodiment of the present invention, before repairing the photomask, the photomask may be detected, and the photomask with defects may be selected as the photomask to be repaired, and any detection method known to those skilled in the art may be used to detect the photomask.

In one example, a method of defining a pattern to be repaired having a defect includes: the method includes the steps of performing simulation detection on wafer exposure on a photomask to be repaired by using a space image measurement system, and defining a pattern with a defect, of which the imaging degree is lower than a target value, as the pattern to be repaired with the defect, according to the imaging degree of the expected photomask defect on the wafer, wherein the pattern with the defect, of which the imaging degree is lower than the target value, is defined as the pattern to be repaired with the defect, namely the pattern to be repaired by using the defect repairing method of the invention, wherein the target value can be any appropriate value meeting the specification, the target value is set according to the process requirements of a user, for example, the target value is 92% at the lowest, and once.

In one example, the location of the defect can be determined by testing the reticle to be repaired, for example, first, obtaining an SEM image of a normal reticle (reticle without defect) or other normal area in the reticle to be repaired, and using the SEM image as a reference image; then, scanning the photomask to be repaired by adopting a scanning machine table to obtain an SEM image of the photomask to be repaired; and comparing the reference pattern with the SEM pattern of the photomask to be repaired to determine the position of the defect in the photomask to be repaired.

In one example, as shown in fig. 5A, the defect 102 is a surface damage of a portion of the transparent substrate in the pattern 101 to be repaired, such as a Quartz damage (Quartz Damage), which may cause a decrease in the transmittance of the transparent substrate, and the result of the AIMS test shows that the energy intensity is lower than that of a normal portion, thereby affecting the imaging quality of the reticle, and thus requiring repair.

It should be noted that, in the present embodiment, the defect repairing method of the present invention is mainly explained and explained by taking the quartz defect as an example, but the defect repairing method of the present embodiment is not only applicable to the above defect, but also applicable to other defects affecting the transmittance of the light-transmitting pattern, such as a defect of a micro contaminant in the light-transmitting pattern.

Exemplarily, in fig. 5A and 5B, the light transmission pattern having a substantially square shape is illustrated, but the shape of the light transmission pattern of the present invention is not limited thereto, and may be any other shape, such as a circle, a polygon, and the like.

Next, step two is executed to form a plurality of light-transmitting scattering bars 103 on the outer side of the pattern to be repaired 101, so as to perform optical compensation on the pattern to be repaired 101, as shown in fig. 5A.

Illustratively, as shown in fig. 5A, the scattering bars 103 are opaque to light in the region between the side edges of the adjacent pattern 101 to be repaired.

For example, as shown in fig. 5A, the shape of the pattern to be repaired 101 is square, one scattering bar 103 is disposed outside each side of the pattern to be repaired 101, and each scattering bar 103 is disposed parallel to the corresponding side of the pattern to be repaired 101 and separated by an opaque region.

In another example, as shown in fig. 5B, the scattering bars 203 are disposed outside each corner of the pattern 101 to be repaired, wherein each scattering bar 203 includes a first sub-scattering bar and a second sub-scattering bar which are respectively opposite to and parallel to different sides of the pattern 101 to be repaired, for example, the scattering bar 203 is in a zigzag shape, wherein an end point of the first sub-scattering bar is connected with an end point of the second sub-scattering bar, and preferably, the zigzag scattering bars are bent toward the center of the pattern to be repaired.

Illustratively, as shown in fig. 5B, there is a space between adjacent scattering bars 203, i.e., adjacent scattering bars are separated by an opaque region.

Further, the first sub scattering bar and the second sub scattering bar perpendicularly intersect.

In one example, as shown in fig. 5B, the pattern to be repaired is square, and has four corners, and one scattering bar 203 is disposed at intervals outside the four corners.

In one example, the method of forming the light-transmissive plurality of scattering bars includes: and etching the area of the light shielding layer, which is scheduled to form the scattering strip, so as to form an opening exposing the light-transmitting substrate of the photomask, wherein the opening is used as the scattering strip.

The photomask is used for transferring a pattern to a substrate by using an exposure unit, and the scattering strip in the embodiment has the function of performing optical compensation on the adjacent pattern to be repaired, wherein the pattern of the scattering strip is not transferred to the substrate.

Wherein the translucent pattern and the scattering bars are regions having a higher transmittance than other regions on the mask, the translucent pattern allowing a sufficient amount of light to pass therethrough, when the light emitted from the light source is radiated onto the mask, an exposure feature having a light intensity distribution with a higher light intensity in a region corresponding to the translucent pattern is generated, and the scattering bars assist the translucent pattern with a higher degree of light. The pattern of the scattering bars is not a pattern required by design, and therefore, the pattern of the scattering bars cannot be transferred to the substrate, and the size of the scattering bars can be set appropriately so that light passing through the scattering bars cannot be resolved on the substrate (so that the size of the scattering bars is not greater than a resolution limit), for example, the scattering bars are set to have an unresolved width (for example, 20nm to 70 nm).

It should be noted that the scattering bars are also arranged according to the design rule to avoid affecting other adjacent normal patterns.

The method for repairing the photomask of the invention is used for repairing the defect such as quartz damage, before the quartz damage defect shown in figure 6 is repaired, the detection results of the quartz damage defect are about X84% and Y84% through AIMS simulation imaging detection, the values are lower than the target value, after the quartz damage defect is repaired by the method shown in figure 5A, the detection results of the quartz damage defect respectively reach X107% and Y105% through AIMS simulation imaging detection, and after the quartz damage defect is repaired by the method shown in figure 5B, the detection results of the quartz damage defect respectively reach X106% and Y103% through AIMS simulation imaging detection, the detection results respectively meet the target value, therefore, the method successfully repairs the photomask defect, and the photomask pattern meets the design requirements. In addition, the repair method of the invention is repeatedly tested to find that the repair method has good repeatability and high success rate of defect repair, as shown in fig. 7.

Thus, the description of the key steps of the method for repairing the defects of the photomask is completed, and the complete method may include other steps, which are not described herein again.

In summary, in the method for repairing a defect of a photomask and the photomask of the embodiments of the present invention, the light-transmissive scattering bars are formed on the outer side of the pattern to be repaired to perform light compensation on the pattern to be repaired, so as to repair the photomask having the defect and obtain the photomask meeting the design requirement.