阅读说明：本技术 相位移光罩缺陷补偿方法、装置及相位移光罩 (Phase shift mask defect compensation method and device and phase shift mask ) 是由 不公告发明人 于 2018-09-07 设计创作，主要内容包括：本发明涉及一种相位移光罩缺陷补偿方法、装置及相位移光罩,方法包括：根据提供的相位移光罩,获取相位移光罩的参数；根据相位移光罩的参数建立检测模型；通过检测模型结合照明条件以及晶圆的光刻胶性质,计算出相位移光罩中的相位移垫层图案上的缺陷区域；缺陷区域为相位移光罩曝光时导致晶圆的表面出现破口的区域；根据缺陷区域的边界,确定需要覆盖在缺陷区域上的不透光层的边界；不透光层覆盖缺陷区域。本发明实施例通过检测相位移垫层图案中的缺陷区域,并在缺陷区域上覆盖不透光层,实现在通过相位移光罩对晶圆曝光时,在不透光层的作用下,与缺陷区域对应的晶圆表面位置处不再出现破口。(The invention relates to a phase shift photomask defect compensation method, a phase shift photomask defect compensation device and a phase shift photomask, wherein the method comprises the following steps: acquiring parameters of the phase shift mask according to the provided phase shift mask; establishing a detection model according to the parameters of the phase shift photomask; calculating a defect area on a phase shift cushion layer pattern in the phase shift photomask by combining the detection model with the illumination condition and the photoresist property of the wafer; the defect area is an area which causes the surface of the wafer to have a break when the phase shift photomask is exposed; determining the boundary of the non-light-transmitting layer which needs to be covered on the defect region according to the boundary of the defect region; the opaque layer covers the defect area. According to the embodiment of the invention, the defect area in the phase shift cushion layer pattern is detected, and the non-light-pervious layer covers the defect area, so that when the wafer is exposed through the phase shift photomask, under the action of the non-light-pervious layer, the position of the surface of the wafer corresponding to the defect area does not have a break.)

1. A method for compensating phase shift mask defects, comprising:

acquiring parameters of the phase shift mask according to the provided phase shift mask, wherein the phase shift mask is provided with a phase shift cushion layer pattern and a phase shift circuit pattern; the length and width or the diameter of the phase shift cushion layer pattern is more than or equal to 200nm, and the line width of the phase shift line pattern is less than or equal to 40 nm;

establishing a detection model according to the parameters of the phase shift photomask;

calculating a defect region in the phase shift cushion layer pattern in the phase shift photomask by combining the detection model with the illumination condition and the photoresist property of the wafer; wherein the defect region is a region that causes a break on the surface of the wafer when the phase shift mask is exposed, and the defect region is more separated from the phase shift line pattern relative to the phase shift pad layer pattern; and

determining a second boundary of a non-light-transmitting layer required to cover the defect region according to the first boundary of the defect region; wherein the second boundary of the opaque layer is located between the first boundary of the defect region and the adjacent boundary of the phase shift pad layer pattern, for covering the defect region.

2. The method of compensating for phase shifting mask defects of claim 1, further comprising:

and according to the determined second boundary of the opaque layer, covering the opaque layer on the defect region so that no break is generated in the region corresponding to the cushion layer pattern on the surface of the wafer when the phase shift mask is exposed.

3. The method of claim 1, wherein the phase shifting mask parameters comprise: the transmittance of the phase shift mask and the area of the phase shift pad layer pattern.

4. The method of compensating for phase shifting mask imperfections of claim 3, further comprising:

judging whether the area of the phase shift cushion layer pattern is larger than a preset detection area or not;

and when the area of the phase shift cushion layer pattern is larger than the preset detection area, executing a step of establishing a detection model according to the parameters of the phase shift mask.

5. The method of compensating for phase shifting mask imperfections of claim 3, further comprising:

judging whether the area of the phase shift cushion layer pattern is larger than a preset detection area or not;

when the area of the phase shift cushion layer pattern is larger than the preset detection area, calculating the light intensity of the phase shift mask projected onto the wafer by combining the illumination condition, the photoresist property of the wafer and the penetration rate of the phase shift mask through a light intensity model;

judging whether the light intensity is smaller than a preset developing light intensity;

and when the light intensity is smaller than the preset developing light intensity, executing the step of establishing a detection model according to the parameters of the phase shift photomask.

6. The method of compensating for phase shifting mask defects of claim 1, further comprising:

and correcting the determined second boundary of the light-impermeable layer.

7. The method of compensating for phase shifting mask defects of claim 1, further comprising:

and after the phase shift cushion layer pattern is covered with the light-tight layer, re-determining the tangent point of the process window of the phase shift cushion layer pattern.

8. The method for compensating defects in a phase-shifting mask according to any one of claims 1 to 7, wherein the opaque layer is made of chromium.

9. The method of any of claims 1 to 7, wherein the light-impermeable layer comprises a silicon-molybdenum-oxynitride layer having a light transmittance of 6% or less.

10. The method for compensating the phase shift mask defect of any one of claims 1-7, wherein the opaque layer is rectangular or has the same shape as the outer contour of the defect region, and the distance from the first boundary of the defect region to the second boundary of the opaque layer is 5-10 nm.

11. A phase shift mask defect compensation apparatus, comprising:

the acquisition module is used for acquiring parameters of the phase shift photomask according to the provided phase shift photomask;

the modeling module is used for establishing a detection model according to the parameters of the phase shift photomask;

the detection module is used for calculating a defect area on a phase shift cushion layer pattern in the phase shift photomask by combining the illumination condition and the photoresist property of the wafer through the detection model; the defect area is an area which causes a break on the surface of the wafer when the phase shift mask is exposed; and

and the determining module is used for determining a second boundary of the light-tight layer which needs to be covered on the defect region according to the first boundary of the defect region.

12. The phase shifting mask defect compensation apparatus of claim 11, further comprising:

and the compensation module is used for covering the defect region with the light-tight layer according to the determined second boundary of the light-tight layer so that no break is generated in the region corresponding to the phase shift cushion layer pattern on the surface of the wafer when the phase shift photomask is exposed.

13. The phase shifting mask defect compensation apparatus of claim 11, further comprising:

the first judgment module is used for judging the size of the area of the phase shift cushion layer pattern and a preset detection area; and if the area of the phase shift cushion layer pattern is larger than the preset detection area, executing a step of establishing a detection model according to the parameters of the phase shift photomask.

14. The phase shifting mask defect compensation apparatus of claim 13, further comprising:

the second judgment module is used for judging the size of the area of the phase shift cushion layer pattern and the preset detection area; if the area of the phase shift cushion layer pattern is larger than the preset detection area, calculating the light intensity of the phase shift mask projected onto the wafer by combining the illumination condition, the photoresist property of the wafer and the penetration rate of the phase shift mask through a light intensity model; and if the light intensity is less than the preset developing light intensity, executing the step of establishing a detection model according to the parameters of the phase shift photomask.

15. A phase shifting mask, comprising:

a light-transmitting substrate;

the phase shift pad layer pattern and the phase shift line pattern are arranged on the light-transmitting substrate, the length and width or the diameter of the phase shift pad layer pattern is greater than or equal to 200nm, the line width of the phase shift line pattern is less than or equal to 40nm, the phase shift pad layer pattern is provided with a defect area, the defect area is an area which causes the surface of a wafer to be cracked when the phase shift photomask is exposed, and the defect area is more separated from the phase shift line pattern relative to the phase shift pad layer pattern; and

and the second boundary of the light-tight layer is positioned between the first boundary of the defect region and the adjacent boundary of the phase shift cushion layer pattern and is used for covering the defect region.

16. The phase shift mask of claim 15, wherein the phase shift pad pattern comprises a pattern layer having a light transmittance of 20-30% greater than that of the opaque layer.

17. The phase shift mask of claim 15, wherein the phase shift pad pattern and the phase shift line pattern are groove structures formed in the transparent substrate, or the phase shift pad pattern and the phase shift line pattern are protrusion structures integrally formed on the transparent substrate.

18. The phase shift mask of claim 15, wherein the material of the opaque layer comprises chromium.

19. The phase shift mask of claim 15, wherein the opaque layer comprises a molybdenum silicon oxynitride layer having a light transmittance of 6% or less.

20. The phase-shift mask according to any of claims 15 to 19, wherein the opaque layer is rectangular or has the same shape as the outer contour of the defect region, and the distance from the first boundary of the defect region to the second boundary of the opaque layer is 5 to 10 nm.

Technical Field

The present invention relates to the field of lithography technologies, and in particular, to a method and an apparatus for compensating for phase shift mask defects, and a phase shift mask.

Background

In the background art, a Phase Shift Mask (PSM) is mainly used to accurately and clearly transfer a pre-designed electronic circuit layout pattern onto a wafer. Due to the different transmittance of the phase shift mask, when exposing a wafer, as the transmittance of the phase shift mask increases, a recess or an opening may appear at a pattern position with a larger area formed on the wafer. So that the pattern on the phase shift mask cannot be completely transferred to the wafer. For example, as shown in fig. 1, when a phase shift mask with a transmittance of 15% is used for exposure, if the size of the designed pattern on the phase shift mask is large, a recess 202 is formed on the wafer 200 at the position of the lithography pattern 201 corresponding to the pattern after exposure. As shown in fig. 2, when the phase shift mask with a transmittance of 30% is used for exposure, if the size of the pattern designed on the phase shift mask is larger, the central portion of the position of the lithographic pattern 201 corresponding to the pattern on the wafer 200 will be completely penetrated after the exposure, so as to form an opening 203. Thereby causing the wafer to be scrapped and reducing the yield of the wafer.

The above information disclosed in the background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is known to a person of ordinary skill in the art.

Disclosure of Invention

Accordingly, embodiments of the present invention provide a method and an apparatus for compensating phase shift mask defects, and a phase shift mask, so as to solve or alleviate the technical problems in the prior art and provide at least one useful choice.

The technical scheme of the embodiment of the invention is realized as follows:

according to a first aspect of the present invention, there is provided a method for compensating phase shift mask defects, comprising:

acquiring parameters of the phase shift mask according to the provided phase shift mask, wherein the phase shift mask is provided with a phase shift cushion layer pattern and a phase shift circuit pattern; the length and width or the diameter of the phase shift cushion layer pattern is more than or equal to 200nm, and the line width of the phase shift line pattern is less than or equal to 40 nm;

establishing a detection model according to the parameters of the phase shift photomask;

calculating a defect region in the phase shift cushion layer pattern in the phase shift photomask by combining the detection model with the illumination condition and the photoresist property of the wafer; wherein the defect region is a region that causes a break on the surface of the wafer when the phase shift mask is exposed, and the defect region is more separated from the phase shift line pattern relative to the phase shift pad layer pattern; and

determining a second boundary of a non-light-transmitting layer required to cover the defect region according to the first boundary of the defect region; wherein the second boundary of the opaque layer is located between the first boundary of the defect region and the adjacent boundary of the phase shift pad layer pattern, for covering the defect region.

In some embodiments, further comprising:

and according to the determined second boundary of the opaque layer, covering the opaque layer on the defect region so that no break is generated in the region corresponding to the cushion layer pattern on the surface of the wafer when the phase shift mask is exposed.

In some embodiments, the parameters of the phase shift mask include at least: the transmittance of the phase shift mask and the area of the phase shift pad layer pattern.

In some embodiments, further comprising:

judging whether the area of the phase shift cushion layer pattern is larger than a preset detection area or not;

and when the area of the phase shift cushion layer pattern is larger than the preset detection area, executing a step of establishing a detection model according to the parameters of the phase shift mask.

In some embodiments, further comprising:

judging whether the area of the phase shift cushion layer pattern is larger than a preset detection area or not;

when the area of the phase shift cushion layer pattern is larger than the preset detection area, calculating the light intensity of the phase shift mask projected onto the wafer by combining the illumination condition, the photoresist property of the wafer and the penetration rate of the phase shift mask through a light intensity model;

judging whether the light intensity is smaller than a preset developing light intensity;

and when the light intensity is smaller than the preset developing light intensity, executing the step of establishing a detection model according to the parameters of the phase shift photomask.

In some embodiments, further comprising:

and correcting the determined second boundary of the light-impermeable layer.

In some embodiments, further comprising:

and after the cushion layer pattern is covered with the light-tight layer, re-determining the tangent point of the process window of the cushion layer pattern.

In some embodiments, the material of the light-impermeable layer comprises chromium.

In some embodiments, the opaque layer comprises a molybdenum silicon oxynitride layer having a light transmission rate of 6% or less.

In some embodiments, the opaque layer is rectangular or has the same shape as the outline of the defect region, and the distance from the first boundary of the defect region to the second boundary of the opaque layer is 5-10 nm.

According to a second aspect of the present invention, there is provided a phase shift mask defect compensation apparatus, comprising:

the acquisition module is used for acquiring parameters of the phase shift photomask according to the provided phase shift photomask;

the modeling module is used for establishing a detection model according to the parameters of the phase shift photomask;

the detection module is used for calculating a defect area on a phase shift cushion layer pattern in the phase shift photomask by combining the illumination condition and the photoresist property of the wafer through the detection model; the defect area is an area which causes a break on the surface of the wafer when the phase shift mask is exposed; and

and the determining module is used for determining a second boundary of the light-tight layer which needs to be covered on the defect region according to the first boundary of the defect region.

In some embodiments, further comprising:

and the compensation module is used for covering the defect region with the light-tight layer according to the determined second boundary of the light-tight layer so that no break is generated in the region corresponding to the phase shift cushion layer pattern on the surface of the wafer when the phase shift photomask is exposed.

In some embodiments, further comprising:

the first judgment module is used for judging the size of the area of the phase shift cushion layer pattern and a preset detection area; and if the area of the phase shift cushion layer pattern is larger than the preset detection area, executing a step of establishing a detection model according to the parameters of the phase shift photomask.

In some embodiments, further comprising:

the second judgment module is used for judging the size of the area of the phase shift cushion layer pattern and the preset detection area; if the area of the phase shift cushion layer pattern is larger than the preset detection area, calculating the light intensity of the phase shift mask projected onto the wafer by combining the illumination condition, the photoresist property of the wafer and the penetration rate of the phase shift mask through a light intensity model; and if the light intensity is less than the preset developing light intensity, executing the step of establishing a detection model according to the parameters of the phase shift photomask.

According to a third aspect of the present invention, there is provided a phase shift mask, comprising:

a light-transmitting substrate;

the phase shift pad layer pattern and the phase shift line pattern are arranged on the light-transmitting substrate, the length and width or the diameter of the phase shift pad layer pattern is greater than or equal to 200nm, the line width of the phase shift line pattern is less than or equal to 40nm, the phase shift pad layer pattern is provided with a defect area, the defect area is an area which causes the surface of a wafer to be cracked when the phase shift photomask is exposed, and the defect area is more separated from the phase shift line pattern relative to the phase shift pad layer pattern; and

and the second boundary of the light-tight layer is positioned between the first boundary of the defect region and the adjacent boundary of the phase shift cushion layer pattern and is used for covering the defect region.

In some embodiments, the phase shift pad layer pattern includes a pattern layer having a light transmittance of 20-30% and greater than that of the opaque layer.

In some embodiments, the phase shift pad layer pattern and the phase shift line pattern are groove structures formed in the transparent substrate, or the phase shift pad layer pattern and the phase shift line pattern are protrusion structures integrally formed on the transparent substrate.

In some embodiments, the material of the light-impermeable layer comprises chromium.

In some embodiments, the opaque layer comprises a molybdenum silicon oxynitride layer having a light transmission rate of 6% or less.

In some embodiments, the opaque layer is rectangular or has the same shape as the outline of the defect region, and the distance from the first boundary of the defect region to the second boundary of the opaque layer is 5-10 nm.

Due to the adoption of the technical scheme, the embodiment of the invention has the following advantages: according to the embodiment of the invention, the defect area in the phase shift cushion layer pattern is detected, and the non-light-pervious layer covers the defect area, so that when the wafer is exposed through the phase shift photomask, under the action of the non-light-pervious layer, the position of the surface of the wafer corresponding to the defect area does not have a break.

The foregoing summary is provided for the purpose of description only and is not intended to be limiting in any way. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features of the present invention will be readily apparent by reference to the drawings and following detailed description.

Drawings

In the drawings, like reference numerals refer to the same or similar parts or elements throughout the several views unless otherwise specified. The figures are not necessarily to scale. It is appreciated that these drawings depict only some embodiments in accordance with the disclosure and are therefore not to be considered limiting of its scope.

FIG. 1 is a diagram illustrating a conventional wafer with a dishing defect after exposure.

FIG. 2 is a diagram illustrating the occurrence of an opening defect after exposure of a wafer in the prior art.

FIG. 3 is a flowchart illustrating a method for compensating phase shift mask defects according to an embodiment of the present invention.

FIG. 4 is a diagram illustrating a defective area on a phase shift pad layer pattern according to an embodiment of the present invention.

FIG. 5 is a diagram illustrating an embodiment of covering a defect region with a light-impermeable layer.

FIG. 6 is a flowchart illustrating a method for compensating phase shift mask defects according to another embodiment of the present invention

FIG. 7 is a flowchart illustrating a method for compensating phase shift mask defects according to another embodiment of the present invention.

Fig. 8 is a schematic view of the phase shift pad layer pattern covering the opaque layer according to the embodiment of the invention.

FIG. 9 is a diagram illustrating a phase shift mask defect compensation apparatus according to an embodiment of the present invention.

FIG. 10 is a diagram illustrating a phase shift mask defect compensation apparatus according to another embodiment of the present invention.

FIG. 11 is a schematic structural diagram of a phase shift mask according to an embodiment of the present invention.

FIG. 12 is a schematic side view of a phase shift mask according to an embodiment of the present invention.

The reference numbers illustrate:

Detailed Description

In the following, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. Accordingly, the drawings and description are to be regarded as illustrative in nature, and not as restrictive.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the device or component in question must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered as limiting the invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; the connection can be mechanical connection, electrical connection or communication; the two components can be directly connected or indirectly connected through an intermediate medium, and the two components can be communicated with each other or mutually interacted. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly above and obliquely above the second feature, or simply meaning that the first feature is at a lesser level than the second feature.

The following disclosure provides many different embodiments or examples for implementing different features of the invention. To simplify the disclosure of the present invention, the components and arrangements of specific examples are described below. Of course, they are merely examples and are not intended to limit the present invention. Furthermore, the present invention may repeat reference numerals and/or letters in the various examples, such repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed. In addition, the present invention provides examples of various specific processes and materials, but one of ordinary skill in the art may recognize applications of other processes and/or uses of other materials.

As shown in fig. 3, an embodiment of the invention provides a method for compensating phase shift mask defects, which includes the following steps:

s100: according to the provided phase shift mask, the parameters of the phase shift mask are obtained. As shown in FIG. 4, the phase shift mask has a phase shift pad pattern 10 and a phase shift line pattern 13. The length, width or diameter of the phase shift pad pattern 10 is not less than 200nm, and the line width of the phase shift line pattern 13 is not more than 40 nm.

S200: and establishing a detection model according to the parameters of the phase shift mask. The established detection model may be stored in association with the phase shift mask parameters. When the phase shift mask with the same or similar parameters is detected again, the stored established detection model can be directly retrieved for direct use. The execution speed of the method of the embodiment is improved.

S300: the defect area 11 on the phase shift pad pattern 10 in the phase shift mask is calculated by the inspection model in combination with the illumination condition and the photoresist property of the wafer (as shown in FIG. 4). The defect region 11 reflects the light intensity in the inner portion of the phase shift pad pattern 10 projected onto the photoresist due to optical diffraction when the phase shift mask is exposed to light on the wafer. Further, during development, the photoresist that is not developed appears in the inner portion area of the phase shift pad layer pattern 10 projected onto the photoresist, which is entirely developed, and a region where a break appears on the surface of the wafer is formed. The defect region 11 is further separated from the phase shift line pattern 13 than the phase shift pad pattern 10 (i.e. the shortest distance from the defect region 11 to the phase shift line pattern 13 is greater than the shortest distance from the phase shift pad pattern 10 to the phase shift line pattern 13). The phase shift pad layer pattern 10 may be used to form pads and/or spaces on a wafer during exposure. The defect region 11 on the phase shift pad pattern 10 can be understood as an invisible virtual region. A breach can be understood as a recess or a through-opening.

S400: from the first boundary 111 of the defect region 11, a second boundary 121 (shown in fig. 5) of the light-opaque layer 12 that needs to be covered on the defect region 11 is determined. Wherein the opaque layer 12 covers the defect region 11.

In one embodiment, as shown in fig. 6, further comprising the steps of:

s500: according to the determined second boundary 121 of the opaque layer 12, the opaque layer 12 covers the defect region 11, so that no crack is generated in the region corresponding to the phase shift pad layer pattern 10 on the surface of the wafer when the phase shift mask is exposed. Due to the arrangement of the opaque layer 12, the incident light is shielded by the opaque layer 12 at the phase shift pad layer pattern 10, so that the penetrating power of the incident light is reduced or even disappears, and the surface of the wafer corresponding to the defect region 11 is effectively prevented from being cracked.

In one embodiment, the opaque layer 12 has an area greater than the area of the defect region. Preferably, the first boundary 111 of the defect region 11 is 5 to 10nm away from the boundary of the opaque layer 12. That is, after the first boundary 111 and the area of the defect region 11 are calculated, the first boundary 111 of the opaque layer 12 to be covered is determined by extending a distance of 5 to 10nm to the outside along the first boundary 111 of the defect region 11 when the opaque layer 12 is covered.

In a preferred embodiment, the area of the opaque layer 12 is larger than that of the defect region 11, and the area of the opaque layer 12 is smaller than that of the phase shift pad layer pattern 10. The opaque layer 12 is located in a region of the phase shift pad layer pattern 10.

In one embodiment, the parameters of the phase shift mask include: the transmittance of the phase shift mask and the area of the phase shift pad pattern 10. Parameters such as the shape, boundary dimensions, material of the phase shift pad pattern 10, and the transmittance of the phase shift pad pattern 10 may also be included. It should be noted that the transmittance of the phase shift mask and the phase shift pad layer pattern 10 may be the same.

In one embodiment, the illumination conditions include at least Numerical Aperture (NA), coherence (sigma), and/or polarization of the light. The photoresist properties of the wafer at least include: refractive index, dielectric constant, and/or diffusion length.

In one embodiment, the method for compensating phase shift mask defects further comprises the steps of:

it is determined whether the area of the phase shift pad pattern 10 is larger than a predetermined detection area.

When the area of the phase shift pad pattern 10 is larger than the predetermined detection area, step S200 of establishing a detection model according to the parameters of the phase shift mask is performed.

When the area of the phase shift pad pattern 10 is smaller than the predetermined detection area, the phase shift pad pattern 10 of the phase shift mask has no defect area, and the process is ended.

Preferably, the area of the detection area is not smaller than 200x200nm is preset.

In one embodiment, the method for compensating phase shift mask defects, as shown in FIG. 7, further comprises the steps of:

s110: it is determined whether the area of the phase shift pad pattern 10 is larger than a predetermined detection area. If the area of the phase shift pad pattern 10 is smaller than the predetermined detection area, the phase shift pad pattern 10 of the phase shift mask has no defect area, and the process is ended. If the area of the phase shift pad pattern 10 is larger than the predetermined detection area, step S120 is performed.

S120: and calculating the light intensity of the phase shift mask projected on the wafer by combining the illumination condition, the photoresist property of the wafer and the penetration rate of the phase shift mask through a light intensity model.

S130: and judging whether the light intensity is smaller than the preset developing light intensity. If the light intensity is less than the preset developing light intensity, step S200 of establishing a detection model according to the parameters of the phase shift mask is performed. If the light intensity is greater than the preset developing light intensity, the phase shift pad layer pattern 10 of the phase shift mask has no defect area, and the process is ended.

It should be noted that the preset detection area and the preset developing light intensity can be selected according to an empirical value, or set according to product requirements.

In one embodiment, the material of the opaque layer 12 comprises chromium (Cr).

In an alternative embodiment, the material of the opaque layer 12 comprises a MoSi or molybdenum silicon oxynitride (MoSiON) layer.

In one embodiment, the method of the present invention is mainly applied to a phase shift mask with a transmittance of not less than 6%. Since the higher the transmittance, the higher the probability of the occurrence of the crack on the wafer, the method of the embodiment of the invention is preferably applied to the phase shift mask with the transmittance not lower than 15%.

In one embodiment, the light impermeable layer 12 comprises a silicon molybdenum oxynitride (MoSiON) layer having a light transmission rate of 6% or less

In one embodiment, the opaque layer 12 is rectangular or the same shape as the outer contour of the defect area.

In one embodiment, the above steps may be executed by one execution body, or may be executed by a plurality of execution bodies. The execution body may be hardware, software, or a combination of hardware and software.

For example, steps S100 to S400 may be performed by ORC (optical rule check) software. Step S500 may be performed by OPC (Optical Proximity Correction) software. As another example, steps S100-S500 are all performed by ORC software, or steps S100-S500 are all performed by OPC software.

In one embodiment, as shown in FIG. 8, in a phase shift mask 100, when the size of the phase shift pad layer pattern 10a is 1000x1000nm, the opaque layer 12 is at least 500x500 nm. When the phase shift pad pattern 10b has a size of 500x500nm, the opaque layer 12 is covered by at least 200x200 nm. When the size of the phase shift pad layer pattern 10c is 200 × 500nm, it is not necessary to cover the opaque layer, and no crack occurs on the wafer during exposure within this size.

In one embodiment, the method for compensating phase shift mask defects further comprises the steps of: after the phase shift pad layer pattern 10 is covered with the opaque layer 12, the process window of the phase shift pad layer pattern 10 is determined again to be tangent. To ensure the accuracy of the tangent point in optical proximity trimming.

An embodiment of the present invention provides a phase shift mask defect compensation apparatus, as shown in fig. 9, including:

the obtaining module 31 is configured to obtain parameters of the phase shift mask according to the provided phase shift mask.

The modeling module 32 is configured to build a detection model according to the parameters of the phase shift mask.

The detection module 33 is configured to calculate a defect region on the phase shift pad pattern in the phase shift mask by using the detection model in combination with the illumination condition and the photoresist property of the wafer; the defect area is an area where a surface of the wafer is cracked when the phase shift mask is exposed.

And the determining module 34 is configured to determine a boundary of the opaque layer to be covered on the defect region according to the boundary of the defect region.

In one embodiment, as shown in fig. 10, the compensation module 35 is configured to cover the defect region with a light-impermeable layer, so that no break is generated in a region corresponding to the phase shift pad layer pattern on the surface of the wafer when the phase shift mask is exposed; wherein, the area of the non-light-transmitting layer is larger than that of the defect region.

In one embodiment, as shown in FIG. 10, the apparatus for compensating phase shift mask defects further comprises:

a first determining module 36, configured to determine the area of the phase shift pad pattern and a preset detection area; and if the area of the phase shift cushion layer pattern is larger than the preset detection area, executing the step of establishing a detection model according to the parameters of the phase shift photomask.

In one embodiment, as shown in FIG. 10, the apparatus for compensating phase shift mask defects further comprises:

a second determining module 37, configured to determine the size of the area of the phase shift pad pattern and a preset detection area; if the area of the phase shift cushion layer pattern is larger than the preset detection area, calculating the light intensity of the phase shift photomask projected on the wafer by combining the illumination condition, the photoresist property of the wafer and the penetration rate of the phase shift photomask through a light intensity model; and if the light intensity is less than the preset developing light intensity, executing the step of establishing a detection model according to the parameters of the phase shift photomask.

An embodiment of the present invention provides a phase shift mask, as shown in fig. 11 and 12, including:

a light-transmissive substrate 300.

The phase shift pad layer pattern 310 and the phase shift line pattern 340 are disposed on the transparent substrate 300. The length, width or diameter of the phase shift pad layer pattern 310 is greater than or equal to 200nm, and the line width of the phase shift line pattern 340 is less than or equal to 40 nm. The phase shift pad pattern 310 has a defect region 330, the defect region 330 is a region of the wafer surface that is damaged when the phase shift mask is exposed, and the defect region 330 is separated from the phase shift line pattern 340 relative to the phase shift pad pattern 310.

And a light opaque layer 320 disposed in the phase shift pad layer pattern 310. The second boundary 3201 of the opaque layer 320 is located between the first boundary 3301 of the defect region 330 and the adjacent boundary 3101 of the phase shift pad layer pattern 310, for covering the defect region.

In one embodiment, the phase shift pad layer pattern 310 has a light transmittance of 20-30%.

In one embodiment, the phase shift pad layer pattern 310 and the phase shift line pattern 340 are groove structures formed on the transparent substrate 300, or the phase shift pad layer pattern 310 and the phase shift line pattern 340 are protrusion structures formed on the transparent substrate. In a specific example, the phase shift pad layer pattern 310 and the phase shift line pattern 340 may be a bump structure attached on a MoSi layer or other known phase shift material layer of the transparent substrate 300.

The high-penetration phase shift mask of the embodiment of the invention not only meets the design requirement of manufacturing fine circuit patterns on a wafer, but also solves the problem of breaking large-area patterns.

The above description is only for the specific embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive various changes or substitutions within the technical scope of the present invention, and these should be covered by the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.