阅读说明：本技术 掩膜版 (Mask plate ) 是由 谭锦丹 孙畅 张翩 于 2021-01-18 设计创作，主要内容包括：本申请公开了一种掩膜版,包括：中心图案区,包括器件结构的光刻图案；第一图案区,包括第一划片道的光刻图案；以及第二图案区,包括第二划片道的光刻图案,其中,第一图案区与第二图案区分别位于中心图案区的两侧且沿平行方向延伸,第二图案区的光刻图案沿第一设定方向的位移图案与第二图案区的光刻图案不存在交叠的透光区,第一设定方向与第一图案区的延伸方向垂直。由于第二图案区的光刻图案沿第一设定方向的位移图案与第二图案区的光刻图案不存在交叠的透光区,防止了前一次光刻步骤经第一图案区形成的光刻图案在后一次光刻步骤中被照射,从而将经第一图案区形成的光刻图案保留在晶圆上。(The application discloses mask version includes: a central pattern region comprising a lithographic pattern of device structures; a first pattern region including a lithographic pattern of the first scribe lane; and the second pattern area comprises photoetching patterns of the second scribing channel, wherein the first pattern area and the second pattern area are respectively positioned at two sides of the central pattern area and extend along the parallel direction, the photoetching patterns of the second pattern area do not have a light-transmitting area overlapped with the photoetching patterns of the second pattern area along the displacement patterns of the first set direction, and the first set direction is vertical to the extending direction of the first pattern area. Because the displacement pattern of the photoetching pattern of the second pattern area along the first set direction and the photoetching pattern of the second pattern area do not have an overlapped light-transmitting area, the photoetching pattern formed by the first pattern area in the previous photoetching step is prevented from being irradiated in the next photoetching step, and the photoetching pattern formed by the first pattern area is reserved on the wafer.)

1. A reticle, comprising:

a central pattern region comprising a lithographic pattern of device structures;

a first pattern region including a lithographic pattern of the first scribe lane; and

a second pattern region including a lithographic pattern of second scribe lanes,

wherein the first pattern area and the second pattern area are respectively positioned at two sides of the central pattern area and extend along the parallel direction,

the displacement pattern of the photoetching pattern of the second pattern area along a first set direction and the photoetching pattern of the first pattern area do not have an overlapped light transmission area,

the first setting direction is perpendicular to the extending direction of the first pattern area.

2. The reticle of claim 1, wherein the second pattern region is opaque.

3. The reticle of claim 1, further comprising:

a third pattern region including a lithographic pattern of a third scribe lane; and

a fourth pattern region including a lithographic pattern of a fourth scribe lane,

wherein the third pattern area and the fourth pattern area are respectively positioned at two sides of the central pattern area and extend along the parallel direction, the extending directions of the first pattern area and the third pattern area are mutually vertical,

the displacement pattern of the photoetching pattern of the fourth pattern area along a second set direction and the photoetching pattern of the third pattern area do not have an overlapped light-transmitting area,

the second setting direction is perpendicular to the extending direction of the third pattern area.

4. The reticle of claim 3, wherein the fourth pattern region is opaque to light.

5. The reticle of claim 3, wherein the lithographic pattern of the first street and the lithographic pattern of the third street comprise a lithographic pattern of an auxiliary structure for forming overlay marks of a wafer test structure and/or a wafer.

6. The reticle of any one of claims 1-5, wherein the central pattern region further comprises a spacer portion, the lithographic pattern of the device structure being a plurality, the lithographic patterns of the device structure being separated by the spacer portion.

7. Reticle according to any one of claims 1-5, further comprising a light-impermeable border area, such that a set of patterns on the reticle is enclosed by the border area.

8. The reticle of claim 3, wherein the first pattern region further comprises a first positioning pattern region, the second pattern region further comprises a second positioning pattern region,

the first positioning pattern area and the second positioning pattern area are transparent and have the same shape and size,

the first pattern area and the second pattern area are identical in shape and size,

the first positioning pattern region is located at the same position in the first pattern region as the second positioning pattern region is located in the second pattern region.

9. The reticle of claim 8, wherein the first pattern region has a first overlap that coincides with the third pattern region and further has a second overlap that coincides with the fourth pattern region,

the second pattern region has a third overlapping portion overlapping with the third pattern region and a fourth overlapping portion overlapping with the fourth pattern region,

the first positioning pattern areas are two and are respectively positioned in the centers of the first superposition part and the second superposition part, and the second positioning pattern areas are two and are respectively positioned in the centers of the third superposition part and the fourth superposition part.

10. The reticle of claim 9, wherein the first, second, third, and fourth overlaps are square and uniform in size,

the area of the first superposition part except the first positioning pattern area is divided into four auxiliary areas along two central lines of the first superposition part which are vertical to each other, the auxiliary area adjacent to the central pattern area is transparent, and the rest auxiliary areas are opaque,

the pattern formed by the first overlapping part and the second overlapping part is an axisymmetric pattern,

the pattern formed by the first overlapping part and the third overlapping part is an axisymmetric pattern,

the pattern formed by the first overlapping part and the fourth overlapping part is a centrosymmetric pattern.

Technical Field

The invention relates to the technical field of semiconductor manufacturing, in particular to a mask.

Background

The Mask is a graphic master Mask used by a photoetching process commonly used by a micro-nano processing technology. A mask pattern structure is formed on a transparent substrate by an opaque shading film, and pattern information is transferred to a product substrate through an exposure process.

In the related art, some non-device structures need to be formed in the scribe lines of the wafer, and therefore some special design needs to be performed on the mask.

Disclosure of Invention

It is an object of the present invention to provide an improved reticle that prevents a lithographic pattern formed by a first pattern region from a previous lithographic step from being irradiated in a subsequent lithographic step, thereby leaving the lithographic pattern formed by the first pattern region on the wafer.

According to the implementation of the invention, the mask plate comprises: a central pattern region comprising a lithographic pattern of device structures; a first pattern region including a lithographic pattern of the first scribe lane; and a second pattern region including a lithography pattern of a second scribe lane, wherein the first pattern region and the second pattern region are respectively located at both sides of the central pattern region and extend in a parallel direction, a displacement pattern of the lithography pattern of the second pattern region in a first set direction and the lithography pattern of the first pattern region do not have an overlapped light transmission region, and the first set direction is perpendicular to the extending direction of the first pattern region.

Optionally, the second pattern region is opaque.

Optionally, the method further comprises: a third pattern region including a lithographic pattern of a third scribe lane; and a fourth pattern area including a lithography pattern of a fourth scribe lane, wherein the third pattern area and the fourth pattern area are respectively located at two sides of the central pattern area and extend in parallel directions, the extending directions of the first pattern area and the third pattern area are mutually perpendicular, a displacement pattern of the lithography pattern of the fourth pattern area along a second set direction and the lithography pattern of the third pattern area do not have a light transmission area overlapped, and the second set direction is perpendicular to the extending direction of the third pattern area.

Optionally, the fourth pattern region is opaque.

Optionally, the lithography pattern of the first scribe lane and the lithography pattern of the third scribe lane include a lithography pattern of an auxiliary structure, and the lithography pattern of the auxiliary structure is used for forming an overlay mark of a wafer test structure and/or a wafer.

Optionally, the central pattern region has a spacer portion and a plurality of device regions separated by the spacer portion, each of the device regions respectively corresponding to the lithographic pattern of the device structure.

Optionally, the mask further comprises a frame region which is not transparent to light, so that the pattern set on the mask is enclosed by the frame region.

Optionally, the first pattern area further includes a first positioning pattern area, the second pattern area further includes a second positioning pattern area, the first positioning pattern area and the second positioning pattern area are both transparent and have the same shape and size, the first pattern area and the second pattern area have the same shape and size, and the first positioning pattern area is located at the same position as the second positioning pattern area in the first pattern area.

Optionally, the first pattern area has a first overlapping portion overlapping with the third pattern area, and further has a second overlapping portion overlapping with the fourth pattern area, the second pattern area has a third overlapping portion overlapping with the third pattern area, and further has a fourth overlapping portion overlapping with the fourth pattern area, where the number of the first positioning pattern areas is two and is located at the center of the first overlapping portion and the center of the second overlapping portion, respectively, and the number of the second positioning pattern areas is two and is located at the center of the third overlapping portion and the center of the fourth overlapping portion, respectively.

Optionally, the first, second, third, and fourth overlapping portions are square and have the same size, an area of the first overlapping portion except the first positioning pattern area is divided into four auxiliary areas along two central lines perpendicular to each other of the first overlapping portion, the auxiliary area adjacent to the central pattern area is transparent, the rest of the auxiliary areas are opaque, a pattern formed by the first overlapping portion and the second overlapping portion is an axisymmetric pattern, a pattern formed by the first overlapping portion and the third overlapping portion is an axisymmetric pattern, and a pattern formed by the first overlapping portion and the fourth overlapping portion is a centrosymmetric pattern.

The mask provided by the embodiment of the invention prevents the photoetching pattern formed by the first pattern area in the previous photoetching step from being irradiated in the next photoetching step by arranging the first pattern area and the second pattern area and arranging the light transmission area in which the displacement pattern of the photoetching pattern of the second pattern area along the first set direction does not overlap with the photoetching pattern of the second pattern area, thereby keeping the photoetching pattern formed by the first pattern area on the wafer.

Drawings

The above and other objects, features and advantages of the present invention will become more apparent from the following description of the embodiments of the present invention with reference to the accompanying drawings.

Fig. 1 shows a schematic structural diagram of a reticle in the related art.

Fig. 2a to 2d show the structure of the wafer.

Fig. 3a and 3b are schematic diagrams illustrating a principle of photolithography on a wafer by using a reticle in the related art.

Fig. 4a and 4b are schematic structural diagrams of a reticle according to a first embodiment of the present invention.

Fig. 5a and 5b are schematic diagrams illustrating a principle of photolithography on a wafer by using the mask according to the first embodiment of the present invention.

Fig. 6a to 6c are schematic structural views of a reticle according to a second embodiment of the present invention.

Fig. 7a and 7b are schematic diagrams illustrating the principle of photolithography on a wafer by using a reticle according to a second embodiment of the present invention.

Detailed Description

The invention will be described in more detail below with reference to the accompanying drawings. Like elements in the various figures are denoted by like reference numerals. For purposes of clarity, the various features in the drawings are not necessarily drawn to scale. In addition, certain well known components may not be shown.

The present invention may be embodied in various forms, some examples of which are described below.

Fig. 1 shows a schematic structural diagram of a reticle in the related art.

As shown in fig. 1, a reticle 100 in the related art includes a center pattern region 110 and an edge pattern region surrounding the center pattern region 110, wherein the edge pattern region includes: a light-transmitting portion 120, a predetermined pattern 131, and a predetermined pattern 132. The predetermined pattern 131 is located at one side of the center pattern region 110 in the X-axis direction, and the predetermined pattern 132 is located at one side of the center pattern region 110 in the Y-axis direction, which is perpendicular to the Y-axis direction. The center pattern region 110, the predetermined pattern 131, and the predetermined pattern 132 are surrounded by the light-transmitting portion 120.

Fig. 2a to 2d show the structure of the wafer, wherein fig. 2a shows the planar structure of the wafer, and fig. 2b to 2d show the enlarged structure of the block 10 in fig. 2 a.

As shown in fig. 2a, the wafer 200 has a plurality of units to be photoetched 210, and the surface of the wafer 200 is coated with the photoresist 300, and each unit to be photoetched 210 has the same structure. As shown in fig. 2b and 2c, to distinguish the cells to be lithographed, the two cells to be lithographed in block 10 are labeled 210a and 210b, respectively.

Each unit to be lithographically patterned includes a device region 211 (a portion for forming a device structure), first and second scribe lanes 221 and 222 located on both sides of the device region 211 in the X-axis direction, and third and fourth scribe lanes 223 and 224 located on both sides of the device region 211 in the Y-axis direction. The first scribe line 221 and the second scribe line 222 are parallel and extend along the Y-axis direction, and the third scribe line 223 and the fourth scribe line 224 are parallel and extend along the X-axis direction.

In order to shorten the exposure time and improve the throughput of the lithography system, the unit to be lithographed is arranged such that the first scribe lane 221 of the unit to be lithographed 210a overlaps the second scribe lane 222 of the adjacent unit to be lithographed 210b along the X-axis direction, as shown in fig. 2 d. Similarly, along the Y-axis direction, the third scribe lane 223 of the unit to be lithographed overlaps the fourth scribe lane 224 of the adjacent unit to be lithographed (not shown).

Fig. 3a and 3b are schematic diagrams illustrating a principle of photolithography on a wafer by using a reticle in the related art. The principle of lithography will be described below with reference to fig. 1, 2a to 2d, and 3a and 3 b.

When the wafer 200 is subjected to photolithography by using the step-and-scan photolithography process, the reticle 100 needs to be aligned with one of the cells to be subjected to photolithography on the wafer 200 in each photolithography step. The central pattern region 110 of the mask corresponds to the device region 211 of the wafer, the edge pattern region of the mask 100 corresponds to the scribe lane of the wafer 200, and more specifically, the predetermined pattern 131 corresponds to the first scribe lane 221, and the predetermined pattern 132 corresponds to the third scribe lane 223.

As shown in fig. 3a, after the unit to be photoetched 210a is photoetched, the pattern of the reticle 100 is transferred to the unit to be photoetched 210a of the wafer, and the photoresist corresponding to the light-transmitting portion 120 of the reticle 100 is removed, so that the structural layer 201 below the photoresist is exposed. Further, after the adjacent unit to be photoetched 210b is photoetched, the pattern of the reticle 100 is transferred to the unit to be photoetched 210b of the wafer, as shown in fig. 3 b. However, in the scribe lane where the unit to be lithographed 210a overlaps the unit to be lithographed 210b, the lithography pattern 202 corresponding to the preset pattern 131 is secondarily exposed to be removed. Similarly, the lithographic pattern corresponding to the predetermined pattern 132 is removed in a subsequent lithographic step. Therefore, the mask needs to be further improved so that the lithography patterns formed in each unit to be lithographed, which correspond to the preset patterns 131 and 132, respectively, are retained.

Fig. 4a and 4b are schematic structural diagrams of a reticle according to a first embodiment of the present invention.

As shown in fig. 4a, a reticle 400 according to a first embodiment of the present invention includes: a center pattern region 410, a first pattern region 421, and a second pattern region 422. Referring to fig. 2b and 4a, the central pattern region 410 includes a lithographic pattern 401 of a device structure, and the central pattern region 410 corresponds to a device region 211 in a unit to be lithographically patterned. The first pattern region 421 includes the lithography pattern 403a of the first scribe lane, and the first pattern region 421 corresponds to the first scribe lane 221 in the unit to be lithographed. The second pattern region 422 includes the lithography pattern 404a of the second scribe lane, and the second pattern region 422 corresponds to the second scribe lane 222 in the unit to be lithographed. The first pattern area 421 and the second pattern area 422 are respectively located on two sides of the central pattern area 410 along the X-axis direction and extend along the Y-axis direction.

With further reference to fig. 4b, the reticle 400 of the first embodiment of the present invention further comprises: a third pattern region 423, and a fourth pattern region 424. Referring to fig. 2b and 4b, the third pattern region 423 includes a lithography pattern 403b of a third scribe lane, and the third pattern region 423 corresponds to the third scribe lane 223 in the unit to be lithographed. Fourth pattern region 424 includes lithographic pattern 404b of a fourth scribe lane, fourth pattern region 424 corresponding to fourth scribe lane 224 in the cell to be lithographically patterned. The third pattern region 423 and the fourth pattern region 424 are respectively located on two sides of the central pattern region 410 along the Y-axis direction and extend along the X-axis direction.

In the first, second, third and fourth pattern regions 421, 422, 423 and 424 of the present embodiment, except for the lithographic patterns 403a, 404a, 403b and 404b, the remaining portions are all transparent portions 402, and the lithographic patterns 404a and 404b are opaque and have a light masking function. The lithography patterns 403a and 403b are lithography patterns of auxiliary structures including wafer test structures and/or overlay marks of the wafer, and in some embodiments, the lithography patterns 403a and 403b have light-transmissive regions therein. Of course, in some other embodiments, the lithographic patterns 403a and 403b do not have light transmissive regions therein. The displacement pattern of the lithography pattern 404a in the X direction (first setting direction) has no light transmission region overlapping with the lithography pattern 403 a. The displacement pattern of the lithography pattern 404b in the Y direction (second setting direction) has no light transmission region overlapping with the lithography pattern 403 b.

In some embodiments, the shapes and sizes of the first pattern region 421 and the second pattern region 422 are the same, the shapes and sizes of the lithography pattern 403a and the lithography pattern 404a are the same, and the position of the lithography pattern 403a in the first pattern region 421 is the same as the position of the lithography pattern 404a in the second pattern region 422. The third pattern region 423 and the fourth pattern region 424 have the same shape and size, the lithographic pattern 403b and the lithographic pattern 404b have the same shape and size, and the position of the lithographic pattern 403b in the third pattern region 423 and the position of the lithographic pattern 404b in the fourth pattern region 424 also have the same position.

In another embodiment, none of the second pattern areas 422 is transparent, the entire second pattern area 422 is used as the lithographic pattern 404a, none of the fourth pattern areas 424 is transparent, and the entire fourth pattern area 424 is used as the lithographic pattern 404 b.

However, the embodiment of the present invention is not limited thereto, and those skilled in the art may perform other settings on the shapes, sizes and positional relationships of the patterns 403a, 404a, 403b and 404b according to the requirements, but the requirements of the light-transmitting region where the displacement pattern of the lithographic pattern 404a along the X direction does not overlap with the lithographic pattern 403a, and the light-transmitting region where the displacement pattern of the lithographic pattern 404b along the Y direction does not overlap with the lithographic pattern 403b are satisfied.

In this embodiment, reticle 400 further includes a frame region 430 that is opaque such that the collection of patterns on reticle 400 is enclosed by frame region 430.

Fig. 5a and 5b are schematic diagrams illustrating a principle of photolithography on a wafer by using the mask according to the first embodiment of the present invention.

When a step-and-scan lithography process is used to lithographically etch a wafer, it is necessary to align the reticle 400 with one of the cells to be lithographically etched on the wafer 200 in each lithography step.

After the photolithography is performed on the unit to be lithographed 210a, the pattern of the reticle 400 is transferred to the unit to be lithographed 210a of the wafer, as shown in FIG. 5 a. Further, after the adjacent unit to be photoetched 210b is photoetched, the pattern of the mask 400 is transferred to the unit to be photoetched 210b of the wafer.

Since the pattern 203 formed by the first pattern region is protected from light irradiation by the photolithography pattern 404a of the reticle 400 in the first scribe lane overlapping the second scribe lane, the pattern 203 remains on the wafer 200. Similarly, the lithographic pattern formed by the second pattern region is retained in subsequent lithographic steps.

Fig. 6a to 6c are schematic structural views of a reticle according to a second embodiment of the present invention.

As shown in fig. 6a, a reticle 500 according to a second embodiment of the present invention includes: a central pattern area 510, a first pattern area 521, and a second pattern area 522. Referring to fig. 2b and 6a, the central pattern region 510 includes a plurality of lithography patterns 501a of a device structure, and the central pattern region 510 corresponds to the device region 211 in a unit to be lithographed. The first pattern region 521 includes a lithography pattern 503a of a first scribe lane, and the first pattern region 521 corresponds to the first scribe lane 221 in a unit to be lithographed. The second pattern region 522 includes the lithography pattern 504a of the second scribe lane, and the second pattern region 522 corresponds to the second scribe lane 222 in the unit to be lithographed. In the X-axis direction, the first pattern area 521 and the second pattern area 522 are respectively located at two sides of the central pattern area 510 and both extend along the Y-axis direction. In the present embodiment, the central pattern region 510 further includes a spacer portion 501b, and the plurality of lithography patterns 501a are separated by the spacer portion 501b, wherein the spacer portion 501b transmits light.

With further reference to fig. 6b, the reticle 500 of the second embodiment of the present invention further includes: a third pattern region 523 and a fourth pattern region 524. Referring to fig. 2b and 6b, the third pattern region 523 includes a lithography pattern 503b of a third scribe lane, and the third pattern region 523 corresponds to the third scribe lane 223 in the unit to be lithographically patterned. The fourth pattern region 524 includes the lithography pattern 504b of the fourth scribe lane, and the fourth pattern region 524 corresponds to the fourth scribe lane 224 in the unit to be lithographed. The third pattern region 523 and the fourth pattern region 524 are respectively located on two sides of the central pattern region 510 along the Y-axis direction, and both extend along the X-axis direction.

In the present embodiment, the photo-etching patterns 504a and 504b are opaque and have a photo-masking function. The lithographic patterns 503a and 503b are lithographic patterns of an auxiliary structure including a wafer test structure and/or overlay marks of a wafer, the lithographic patterns 503a and 503b being surrounded by the light-transmissive portion 502. In some embodiments, the lithographic patterns 503a and 503b have light transmissive regions therein. Of course, in some other embodiments, the lithographic patterns 503a and 503b do not have light transmissive regions therein. There is no light-transmitting region where the displacement pattern of the lithography pattern 504a in the X direction (first setting direction) overlaps with the lithography pattern 503 a. There is no light-transmitting region where the displacement pattern of the lithography pattern 504b in the Y direction (second setting direction) overlaps with the lithography pattern 503 b.

With further reference to FIG. 6a, the first pattern region 521 also includes a first positioning pattern region 505 and the second pattern region 522 also includes a second positioning pattern region 506. The first positioning pattern region 505 and the second positioning pattern region 506 are both transparent.

With further reference to fig. 6 a-6 c, the first pattern region 521 has a first coinciding portion 531 coinciding with the third pattern region 523, and the first pattern region 521 also has a second coinciding portion 532 coinciding with the fourth pattern region 524. The second pattern region 522 has a third overlapped portion 533 overlapping with the third pattern region 523, and the second pattern region 522 further has a fourth overlapped portion 534 overlapping with the fourth pattern region 524.

In some preferred embodiments, two first positioning pattern regions 505 are respectively located at the centers of the first overlapping portion 531 and the second overlapping portion 532, and two second positioning pattern regions 506 are respectively located at the centers of the third overlapping portion 533 and the fourth overlapping portion 534.

The first overlapping portion 531, the second overlapping portion 532, the third overlapping portion 533, and the fourth overlapping portion 534 are square and have the same size, an area of the first overlapping portion 531 except the first positioning pattern area 505 is divided into four auxiliary areas along two central lines perpendicular to each other of the first overlapping portion 531, the auxiliary area adjacent to the central pattern area 510 is transparent, the rest of the auxiliary areas are opaque, a pattern formed by the first overlapping portion 531 and the second overlapping portion 532 is an axisymmetric pattern, a pattern formed by the first overlapping portion 531 and the third overlapping portion 532 is an axisymmetric pattern, and a pattern formed by the first overlapping portion 531 and the fourth overlapping portion 534 is a centrosymmetric pattern.

Or stated differently, the light-transmitting portion 502a located in the first overlapping portion 531, the light-transmitting portion 502b located in the second overlapping portion 532, the light-transmitting portion 502c located in the third overlapping portion 533, and the light-transmitting portion 502d located in the fourth overlapping portion 534 are all adjacent to the central pattern region 510. In the case where the first to fourth overlapped portions are overlapped with each other, each first positioning pattern region 505 and each second positioning pattern region 506 are overlapped with each other, and the light-transmitting portion 502a, the light-transmitting portion 502b, the light-transmitting portion 502c, and the light-transmitting portion 502d are adjacent in this order and are complementary to the first positioning pattern region 505/the second positioning pattern region 506. More preferably, when the first to fourth overlapped portions overlap each other, the light transmitting portion 502a, the light transmitting portion 502b, the light transmitting portion 502c, and the light transmitting portion 502d are axisymmetric with each other, or a pattern formed by the light transmitting portion 502a, the light transmitting portion 502b, the light transmitting portion 502c, and the light transmitting portion 502d is centrosymmetric with respect to a center point of the overlapped portion.

In this embodiment, the reticle 500 further includes an opaque border region (not shown) so that the pattern assembly on the reticle 500 is enclosed by the border region, and other parts of the pattern assembly except the pattern of the central pattern region 510 and the lithography patterns 503a and 503b can be automatically generated by a program, thereby achieving the purpose of convenience and rapidity.

Fig. 7a and 7b are schematic diagrams illustrating the principle of photolithography on a wafer by using a reticle according to a second embodiment of the present invention.

When a step-and-scan lithography process is used to lithographically etch a wafer, it is necessary to align the reticle 500 with one of the cells to be lithographically etched on the wafer 200 in each lithography step.

After the unit to be photoetched 210a is photoetched, the pattern of the reticle 500 is transferred to the unit to be photoetched 210a of the wafer, as shown in fig. 7 a. Further, after the adjacent unit to be photoetched 210b is photoetched, the pattern of the reticle 500 is transferred to the unit to be photoetched 210b of the wafer.

Since the lithography pattern 204 formed through the first pattern region is protected from light irradiation by the lithography pattern 504a of the reticle 500 in the first scribe lane overlapping the second scribe lane, the through pattern 204 remains on the wafer 200. Similarly, the lithographic pattern formed by the second pattern region is retained in subsequent lithographic steps.

In the present embodiment, in the overlapped first scribe lane and second scribe lane, a portion of the lithographic pattern corresponding to the first positioning pattern region 505 and a portion of the lithographic pattern corresponding to the second positioning pattern region 506 coincide. In the third scribe lane and the fourth scribe lane which overlap, a portion of the lithographic pattern corresponding to the first positioning pattern region 505 and a portion of the lithographic pattern corresponding to the second positioning pattern region 506 coincide.

The mask provided by the embodiment of the invention is aligned with one of the units to be photoetched on the wafer in each photoetching step, each unit to be photoetched on the wafer is provided with a part for forming a device structure, a first scribing way and a second scribing way, and the first scribing channel of one of the two adjacent units to be photoetched is overlapped with the second scribing channel of the other one, by arranging a first pattern area and a second pattern area which respectively correspond to the two scribing lanes in the mask plate, after a photoetching pattern is formed in one of a certain unit to be photoetched of a wafer through the mask plate, the pattern of the first pattern area is transferred into the first scribing channel, and then in the process of forming the photoetching pattern in the adjacent unit to be photoetched, the second pattern region of the mask plate protects the lithography pattern formed in the first scribe lane from light, thereby leaving the lithography pattern formed through the first pattern region on the wafer.

The second pattern area for protecting the photoetching pattern is opaque so as to completely shield the first scribing channel and the second scribing channel overlapped in the adjacent area to be photoetched.

Or in the case of corresponding to the overlapped first and second scribing lanes, the light-transmitting portion of the first pattern region and the light-transmitting portion of the second pattern region do not overlap each other, thereby preventing the lithographic pattern formed through the light-transmitting portion of the first pattern region from being secondarily exposed.

Furthermore, each unit to be photoetched on the wafer is also provided with a third scribing way and a fourth scribing way, a third pattern area and a fourth pattern area are arranged in the mask, the fourth pattern area is utilized to keep the photoetching pattern formed by the third pattern area on the wafer, and the principle is the same as that of the first pattern area and the second pattern area.

Furthermore, a first positioning pattern area and a second positioning pattern area are respectively arranged in the first pattern area and the second pattern area, and in the overlapped first scribing way and the second scribing way, the part of the photoetching pattern corresponding to the first positioning pattern area and the part of the photoetching pattern corresponding to the second positioning pattern area are overlapped, so that whether the position of the mask plate is aligned with the adjacent area to be photoetched or not can be conveniently identified after the photoetching step of a certain area to be photoetched is finished.

The embodiments of the present invention have been described above. However, these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. The scope of the invention is defined by the appended claims and equivalents thereof. Various alternatives and modifications can be devised by those skilled in the art without departing from the scope of the invention, and these alternatives and modifications are intended to fall within the scope of the invention.