CN110967920A - Double photomask and exposure method - Google Patents
Double photomask and exposure method Download PDFInfo
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- CN110967920A CN110967920A CN201811134790.7A CN201811134790A CN110967920A CN 110967920 A CN110967920 A CN 110967920A CN 201811134790 A CN201811134790 A CN 201811134790A CN 110967920 A CN110967920 A CN 110967920A
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- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
- G03F1/00—Originals for photomechanical production of textured or patterned surfaces, e.g., masks, photo-masks, reticles; Mask blanks or pellicles therefor; Containers specially adapted therefor; Preparation thereof
- G03F1/38—Masks having auxiliary features, e.g. special coatings or marks for alignment or testing; Preparation thereof
- G03F1/42—Alignment or registration features, e.g. alignment marks on the mask substrates
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- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
- G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
- G03F7/70—Microphotolithographic exposure; Apparatus therefor
- G03F7/70216—Mask projection systems
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Abstract
The invention provides a double photomask, which comprises a first photomask and a second photomask, wherein a light-tight region, a plurality of alignment patterns and a pattern size region are formed on the first photomask and the second photomask. The size of the exposure effective pattern obtained by the double photomask is larger than 26x33mm, the alignment problem of a plurality of exposure effective patterns formed by the double photomask in the vertical or horizontal combination can be solved, and the alignment problem between the front layer photomask exposure and the rear layer photomask exposure can be solved when the front layer photomask and the rear layer photomask are laminated in a front-rear layer pair, so that the product can obtain good left-right close fit and front-rear layer alignment. The invention also provides a method for exposure by adopting the double photomask, which has the technical effects.
Description
Technical Field
The invention relates to the technical field of semiconductor manufacturing, in particular to a double photomask and a method for carrying out exposure by adopting the double photomask.
Background
In a photolithography process in a manufacturing process of a semiconductor device, a liquid crystal display device, or the like, an exposure apparatus is used which illuminates a mask (a reticle) with an illumination optical system and projects an image of a pattern of the mask onto a substrate coated with a photosensitive resist layer via a projection optical system.
The current tool size is limited by the tool design, and the maximum size of the exposure area of the mask is 104x132mm, so the size of the exposure area of the standard photomask is usually smaller than this size. Fig. 1 shows a prior art exposure method using a single photomask, in which a light beam passing through the single photomask forms an exposure effective pattern 120 on a wafer 110, however, the exposure effective pattern 120 has a size smaller than 26x33mm according to a 4-fold reduction. In another exposure method using a simple dual photomask, as shown in fig. 2, a light beam passing through the simple dual photomask forms an exposure effective pattern on a wafer 210, and the exposure effective pattern includes a first exposure effective pattern 220 formed by a first photomask a and a second exposure effective pattern 230 formed by a second photomask B. The first exposure effective pattern 220 and the second exposure effective pattern 230 formed by the first photomask a and the second photomask B each have a pattern size smaller than 26x33 mm.
With the increasing requirements of semiconductor processes, it is required to obtain an exposure effective pattern larger than 26x33 mm. However, the above-mentioned single photomask and single dual-photomask adopted in the prior art can not solve the technical problem. Therefore, how to obtain an exposure effective pattern larger than 26 × 33mm is an urgent problem to be solved in the semiconductor technology.
Another problem is that, in the exposure method shown in fig. 1 or fig. 2, when an alignment error is generated at a joint portion of a pattern due to a relative positional deviation of two adjacent exposure regions in exposure, the characteristics of a manufactured device are sometimes impaired. Therefore, it is necessary to reduce the deviation between exposure regions due to manufacturing errors of a photomask for pattern projection, aberrations of a projection optical system, positioning accuracy and movement accuracy of a stage for positioning a photosensitive substrate, and the like, and to ensure bonding accuracy at the time of exposure. In addition, in device manufacturing, since a single-layer pattern formed by exposure is superimposed into a plurality of layers, a superimposition error between exposure regions of the respective layers varies discontinuously at a joint portion of the pattern, resulting in degradation of device quality.
Disclosure of Invention
The present invention provides a twin photomask and exposure method that overcomes or alleviates one or more of the problems of the background art, and provides at least one useful alternative.
As one aspect of the present invention, there is provided a dual photomask including a first photomask and a second photomask;
the first photomask includes:
a first opaque region;
a first partial graphic shape; and
a plurality of alignment patterns;
the second photomask includes:
a second opaque region;
a second partial graphical shape; and
a plurality of alignment patterns;
wherein, the first part of the figure shape and the second part of the figure shape are buckled to form a complete figure shape;
the first light-tight area is positioned on one side of the first photomask close to the second photomask;
the second light-tight area is positioned on one side of the second photomask close to the first photomask.
Preferably, in the above-described twin photomask, the plurality of alignment patterns of the first photomask include: a first alignment pattern, a second alignment pattern, and a third alignment pattern; the plurality of alignment patterns of the second photomask include: a fourth alignment pattern, a fifth alignment pattern, and a sixth alignment pattern; wherein the first alignment pattern and the fourth alignment pattern are used for left-right registration calculation alignment when the first photomask and the second photomask are registered, the second alignment pattern and the fifth alignment pattern are used for left-right registration calculation alignment when the two photomasks are repeatedly registered, and the third alignment pattern and the sixth alignment pattern are used for calculation alignment when the two photomasks of a layer are laminated with the two photomasks of a front layer.
Preferably, in the above-mentioned dual photomask, the first alignment pattern includes at least 4 current layer registration calculation alignment patterns and is located on an upper side and a lower side of the first photomask; the fourth alignment pattern comprises at least 4 current-layer buckling calculation alignment patterns and is positioned on the upper side and the lower side of the second photomask; the second alignment pattern comprises at least 2 current-layer buckling calculation alignment patterns and is positioned on the left side of the first photomask; the fifth alignment pattern comprises at least 2 current-layer buckling calculation alignment patterns and is positioned on the right side of the second photomask; the third alignment pattern comprises at least 4 front-back laminated alignment calculation alignment patterns and is positioned on the upper side and the lower side of the first photomask; the sixth alignment pattern includes at least 4 front-to-back overlay calculation alignment patterns and is located on an upper side and a lower side of the second photomask.
Preferably, the plurality of alignment patterns of the first photomask include: a first alignment pattern, a second alignment pattern, and a third alignment pattern; the plurality of alignment patterns of the second photomask include: a fourth alignment pattern, a fifth alignment pattern, and a sixth alignment pattern; wherein the first alignment pattern and the fourth alignment pattern are used for up-down registration calculation alignment when the first photomask and the second photomask are registered, the second alignment pattern and the fifth alignment pattern are used for up-down registration calculation alignment when the double photomasks are repeatedly registered, and the third alignment pattern and the sixth alignment pattern are used for calculation alignment when the double photomasks on the layer are laminated with the double photomasks on the front layer.
Preferably, in the above-mentioned dual photomasks, the first alignment patterns are located on left and right sides of the first photomask and include at least 4 when-layer calculated alignment patterns; the fourth alignment patterns are positioned on the left side and the right side of the second photomask and comprise at least 4 current-layer buckling calculation alignment patterns; the second alignment pattern is positioned on the lower side of the first photomask and comprises at least 2 current-layer buckling calculation alignment patterns; the fifth alignment pattern is positioned on the upper side of the second photomask and comprises at least 2 current-layer buckling calculation alignment patterns; the third alignment patterns are positioned on the left side and the right side of the first photomask and comprise at least 4 front-back stacking alignment calculation patterns; the sixth alignment patterns are located on the left and right sides of the second photomask and include at least 4 front-to-back overlay calculation alignment patterns.
Preferably, in the above-described twin photomask, the size of the exposure effective pattern formed by the twin photomask is larger than 26 × 33 mm.
Preferably, in the above-described twin photomask, the first partial pattern shape and the second partial pattern shape have different sizes.
Preferably, in the above-described dual photomask, the first opaque region and the second opaque region are covered with a chromium (Cr) film.
Preferably, in the dual photomasks, the first photomask includes a first transparent substrate, a first pattern size region located in the center of the first transparent substrate is disposed on the first transparent substrate, the first opaque region is disposed on one side of the first pattern size region close to the second photomask, and a first transparent region is formed on the remaining three sides of the first pattern size region; the second photomask comprises a second light-transmitting substrate, a second graph size area located in the center of the second light-transmitting substrate is arranged on the second light-transmitting substrate, a second opaque area is arranged on one side, close to the first photomask, of the second graph size area, and a second light-transmitting area is formed on the other three sides of the second graph size area.
Preferably, in the dual photomask, the maximum width of the first light-transmitting substrate is 104mm and the maximum length thereof is 132mm, the maximum width of the first opaque region is 2.5mm, and the maximum width of the first light-transmitting region is 2.5 mm; the maximum width of the second light-transmitting substrate is 104mm, the maximum length of the second light-transmitting substrate is 132mm, the maximum width of the second light-impermeable area is 2.5mm, and the maximum width of the second light-transmitting area is 2.5 mm.
Preferably, in the above-mentioned dual photomasks, the plurality of alignment patterns of the first photomask are disposed in the first light-transmitting region, and the plurality of alignment patterns of the second photomask are disposed in the second light-transmitting region.
Preferably, in the above-described twin photomask, the first partial pattern shape is formed in the first pattern size region, and the second partial pattern shape is formed in the second pattern size region.
The invention also provides an exposure method, which is a method for carrying out exposure by adopting the double photomask and comprises the following steps:
s1: arranging the first photomask above the wafer coated with the photoresist;
s2: carrying out first exposure to obtain a plurality of first exposure effective graphs corresponding to the first photomask on the wafer, wherein gaps exist among the first exposure effective graphs, and the size of each gap corresponds to the size of a corresponding second exposure effective graph formed by exposure of the second photomask;
s3: arranging the second photomask above the wafer;
s4: performing a second exposure to obtain a plurality of second exposure effective patterns corresponding to the second photomask on the wafer, wherein the second exposure effective patterns are positioned between the first exposure effective patterns, and performing an exposure process by using a plurality of alignment patterns;
wherein, the first exposure effective pattern and the second exposure effective pattern are combined to form a complete exposure effective pattern; the size of the complete exposure effective pattern is larger than 26mmx33 mm.
By adopting the photomask and the exposure method, the size of the obtained exposure effective pattern is larger than 26x33mm, the alignment problem among the plurality of double photomasks when the plurality of double photomasks are buckled up and down or left and right can be solved, the alignment problem among the front and back photomasks can be solved when the front and back photomasks are laminated and aligned, and the product can be well adhered left and right and aligned front and back layers.
Drawings
The features and advantages of the present invention will be more clearly understood by reference to the accompanying drawings, which are illustrative and not to be construed as limiting the invention in any way, and in which:
FIG. 1 is a schematic diagram of a single photomask exposure process used in the prior art to form an exposure effective pattern on a wafer.
FIG. 2 is a schematic diagram of a prior art method for forming an exposure effective pattern on a wafer by a simple two-photomask exposure.
Fig. 3 is a schematic view showing a first photomask and a second photomask of the dual photomask according to the present invention.
FIG. 4 is a schematic view of the combination of the exposure of the dual photomasks to form a complete exposure pattern according to the present invention.
FIG. 5 is a schematic view of the present invention combining two complete exposure patterns.
FIG. 6 is a schematic view of the combination of exposure patterns on a wafer formed by exposure of a dual photomask according to the present invention.
Fig. 7 is a schematic view showing two complete exposure effective patterns formed by the combination of the exposure of the front layer and the back layer of the dual photomask, wherein fig. 7a) is a schematic view of two complete exposure effective patterns of the front layer, and fig. 7b) is a schematic view of two complete exposure effective patterns of the current layer.
FIG. 8 is a schematic diagram of the overlay of exposed active patterns formed by the combination of front and back layer dual photomask exposures in accordance with the present invention.
FIG. 9 is a flow chart illustrating an exposure method according to the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example one
The present invention provides a dual photomask having an exposure effective pattern size larger than 26x33mm, as shown in fig. 3, the dual photomask comprising a first photomask a and a second photomask B, wherein the first photomask a and the second photomask B have substantially the same size. In a preferred embodiment, the maximum dimensions of the first photomask a and the second photomask B may be 104mm × 132mm, i.e., a width of 104mm at maximum and a height of 132mm at maximum, according to a 4-fold scaling relationship between the photomasks and the exposure pattern. The first photomask a and the second photomask B include a first substrate 311 and a second substrate 312, respectively. The first substrate 311 and the second substrate 312 comprise glass, preferably quartz glass, and the first substrate 311 and the second substrate 312 may also be made of other kinds of glass or other light-transmissive materials.
In the first photomask a, a first opaque region 321 and a first pattern size region 331 are formed on the first substrate 311. Wherein the first opaque region 321 is formed of, for example, a Cr film. The first opaque region 321 is formed on the right side of the first photomask a, has a rectangular shape, and is aligned up and down with the right edge of the first pattern size area 331, and the first opaque region 321 has a width of 2.5mm at maximum. The first pattern size area 331 is disposed in contact with the first opaque area 321, which is disposed at the left side of the first opaque area 321, and the first pattern size area 331 has a rectangular shape with upper and lower short sides aligned with upper and lower short sides of the first opaque area 321, respectively. The first pattern shape 341 is formed on the right side of the first pattern size area 331. A first light-transmitting region is formed in the first substrate 311 except for the first opaque region 321 and the first pattern size region 331, and includes a first light-transmitting region 351, a second light-transmitting region 361, and a third light-transmitting region 371, wherein the first light-transmitting region 351 is located at an upper side of the first substrate 311, the second light-transmitting region 361 is located at a left side of the first substrate 311, the third light-transmitting region 371 is located at a lower side of the first substrate 311, and the first light-transmitting region 351, the second light-transmitting region 361, and the third light-transmitting region 371 each have a width of not more than 2.5 mm. Thus, in an embodiment where the maximum size of the first photomask a is 104mm x132mm, the first opaque region 321 has a height of not less than 127mm, and the first pattern size area 331 has a width of not less than 99mm and a height of not less than 127 mm.
Symmetrically to the first photomask a, in the second photomask B, the second opaque region 322 and the second pattern size region 332 are formed on the second substrate 312. Wherein the second opaque region 322 is formed of, for example, a Cr film. The second opaque region 322 is formed at the left side of the second photomask B, has a rectangular shape, and is aligned up and down with the left edge of the second pattern size area 332, and the second opaque region 322 has a width of 2.5mm at the maximum. A second pattern size area 332 is disposed in contact with the second opaque region 322 and is disposed at the right side of the second opaque region 322, and the second pattern size area 332 has a rectangular shape with upper and lower short sides aligned with upper and lower short sides of the second opaque region 322, respectively. A second pattern shape 342 is formed at the left side of the second pattern size area 332. A second opaque region 322 and a second pattern size region 332 on the second substrate 312 form a second transparent region, which includes a fourth transparent region 352, a fifth transparent region 362 and a sixth transparent region 372, wherein the fourth transparent region 352 is located on the upper side of the second substrate 312, the fifth transparent region 362 is located on the right side of the second substrate 312, the sixth transparent region 372 is located on the lower side of the second substrate 312, and the fourth transparent region 352, the fifth transparent region 362 and the sixth transparent region 372 each have a width not greater than 2.5 mm. Thus, in an embodiment where the maximum dimension of the second photomask B is 104mm x132mm, the second opaque region 322 has a height of not less than 127mm, and the second pattern size area 332 has a width of not less than 99mm and a height of not less than 127 mm.
The first pattern shape 341 in the first photomask a and the second pattern shape 342 in the second photomask B are buckled to form a complete pattern shape, and in a specific embodiment, as shown in fig. 3, the first pattern shape 341 is a reverse E-shape, and the second pattern shape 342 is a forward E-shape; the first graphic shape 341 and the second graphic shape 342 are snapped together to form a complete "king" shape, as shown in fig. 4. It should be understood that a complete "king" shape formed by the buckling is a pattern formed by combining the respective exposed effective pattern shapes formed by exposing the first photomask a and the second photomask B, and in particular, when the first pattern shape 341 and the second pattern shape 342 are light-transmitting regions, the exposed effective pattern shapes formed by exposing the first pattern shape 341 and the second pattern shape 342 can be combined to form a complete pattern shape due to the existence of the first opaque region 321 and the second opaque region 322.
Based on the above embodiments, since the maximum size of the first photomask a and the second photomask B can be 104mmx132mm, and the size of the complete exposure effective pattern formed by exposing and combining the first photomask a and the second photomask B can exceed 26x33mm according to 4-fold reduction, the technical pain and difficulty that the exposure effective size is smaller than 26x33mm in the prior art are solved.
In order to solve the alignment problem of the complete exposure effective pattern formed by the combination of the first photomask A and the second photomask B during exposure, a first right-left-right buckling calculation alignment pattern 3811 and a second right-left buckling calculation alignment pattern 3812 are formed on the first photomask A, the first right-left-right buckling calculation alignment pattern 3811 and the second right-left buckling calculation alignment pattern 3812 are both formed in the first light-transmitting area 351, the first right-left-right buckling calculation alignment pattern 3811 is positioned on the upper side of the first light-transmitting area 321, and the second right-left buckling calculation alignment pattern 3812 is formed on the left side of the first right-left buckling calculation alignment pattern 3811 and is in contact with the first right-left buckling calculation alignment pattern 3811. Two corresponding current-layer left-right opposite-buckling calculation alignment patterns are arranged in the third light-transmitting area 371 at positions symmetrical to the first current-layer left-right opposite-buckling calculation alignment pattern 3811 and the second current-layer left-right opposite-buckling calculation alignment pattern 3812. A third current-layer left-right registration calculation alignment pattern 3815 is provided at a position above the second light-transmitting region 361, and a current-layer left-right registration calculation alignment pattern that is substantially the same as the third current-layer left-right registration calculation alignment pattern 3815 is also provided at a position below the second light-transmitting region 361. Correspondingly, a fourth right-left-right registration calculation alignment pattern 3821 and a fifth right-left registration calculation alignment pattern 3822 are formed on the second photomask B, the fourth right-left registration calculation alignment pattern 3821 and the fifth right-left registration calculation alignment pattern 3822 are formed in the fourth light-transmitting region 352, the fourth right-left registration calculation alignment pattern 3821 is located above the second light-opaque region 322, and the fifth right-left registration calculation alignment pattern 3822 is formed on the right side of the fourth right-left registration calculation alignment pattern 3821 and contacts the fourth right-left registration calculation alignment pattern 3821. Two corresponding current-layer left-right opposite buckling calculation alignment patterns are also arranged in the sixth light-transmitting area 372 at symmetrical positions of the fourth current-layer left-right opposite buckling calculation alignment pattern 3821 and the fifth current-layer left-right opposite buckling calculation alignment pattern 3822. A sixth current-layer left-right registration calculation alignment pattern 3825 is provided at a position above the fifth light-transmitting region 362, and a current-layer left-right registration calculation alignment pattern substantially identical to the sixth current-layer left-right registration calculation alignment pattern 3825 is also provided at a position below the fifth light-transmitting region 362.
As shown in fig. 4, when the first photomask a and the second photomask B are exposed and combined to form a complete exposure effective pattern, the alignment process is performed by using the first current-layer left-right registration calculation alignment pattern 3811 and the fifth current-layer left-right registration calculation alignment pattern 3822, and the alignment process is performed by using the second current-layer left-right registration calculation alignment pattern 3812 and the fourth current-layer left-right registration calculation alignment pattern 3821. Therefore, the exposure effective pattern formed by exposing the first photomask A and the exposure effective pattern formed by exposing the second photomask B can be completely combined together to form a whole.
Referring to fig. 3 and 5, the first photomask a has a third current-layer left-right registration calculation alignment pattern 3815, the second photomask B has a sixth current-layer left-right registration calculation alignment pattern 3825, the first photomask a and the second photomask B are combined to form a complete exposure effective pattern when exposed, and when a plurality of repeated complete exposure effective patterns are formed, an alignment process is performed using the third current-layer left-right registration calculation alignment pattern 3815 and the sixth current-layer left-right registration calculation alignment pattern 3825. In addition, the current-layer left-right registration calculation alignment pattern, which is substantially the same as the third current-layer left-right registration calculation alignment pattern 3815, provided at a position below the second light-transmitting region 361, also participates in the alignment process, similarly to the current-layer left-right registration calculation alignment pattern, which is substantially the same as the sixth current-layer left-right registration calculation alignment pattern 3825, provided at a position below the fifth light-transmitting region 362.
As shown in fig. 6, a plurality of exposure effective patterns formed by exposure of the dual photomasks may be combined, each of the exposure effective patterns includes a first exposure effective pattern 620 formed by exposure of the first photomask a and a second exposure effective pattern 630 formed by exposure of the second photomask B, so that a pattern covering the entire wafer 610 may be obtained.
The first photomask a and the second photomask B each include a plurality of alignment patterns. In the first photomask a, the first alignment pattern includes a first current-layer left-right registration calculation alignment pattern 3811 and a second current-layer left-right registration calculation alignment pattern 3812, and also includes two corresponding current-layer left-right registration calculation alignment patterns that are arranged in the third light-transmitting region 371 in the same manner as the symmetric positions of the first current-layer left-right registration calculation alignment pattern 3811 and the second current-layer left-right registration calculation alignment pattern 3812, that is, the first alignment pattern may include 4 current-layer left-right registration calculation alignment patterns. The first alignment pattern may include more, i.e., not less than 4, current layer left-right registration calculation alignment patterns for an alignment process when exposing the first photomask a and the second photomask B to a single complete exposure effective pattern formed by combining them. The second alignment pattern includes a third current-layer left-right registration calculation alignment pattern 3815 provided at a position above the second light-transmitting region 361, and also includes a current-layer left-right registration calculation alignment pattern which is substantially the same as the third current-layer left-right registration calculation alignment pattern 3815 and is also provided at a position below the second light-transmitting region 361. The second alignment pattern is used for the alignment process when a plurality of complete exposure effective patterns formed by combining the exposure of the double photomasks are combined. In the second photomask B, the fourth alignment pattern includes a fourth current-layer left-right registration calculation alignment pattern 3821 and a fifth current-layer left-right registration calculation alignment pattern 3822, and also includes two corresponding current-layer left-right registration calculation alignment patterns that are disposed in the sixth light-transmitting region 372 and are the same as the positions where the fourth current-layer left-right registration calculation alignment pattern 3821 and the fifth current-layer left-right registration calculation alignment pattern 3822 are symmetrical, that is, the fourth alignment pattern may include 4 current-layer left-right registration calculation alignment patterns. The fourth alignment pattern may include more, i.e., not less than 4, current layer left-right buckling calculation alignment patterns for an alignment process when exposing the first photomask a and the second photomask B to a single complete exposure effective pattern formed by combining them. The fifth alignment pattern includes a sixth current-layer left-right registration calculation alignment pattern 3825 provided at a position above the fifth light-transmitting region 362, and also includes a current-layer left-right registration calculation alignment pattern which is substantially the same as the sixth current-layer left-right registration calculation alignment pattern 3825 and is also provided at a position below the fifth light-transmitting region 362. The fifth alignment pattern is used for the alignment process when a plurality of complete exposure effective patterns formed by combining the exposure of the double photomasks are combined.
Specifically, the first alignment pattern, the second alignment pattern, the fourth alignment pattern, and the fifth alignment pattern include one or a combination of Bar in Bar, Box in Box, AIM, and uDBO OVL measurement patterns, and the alignment process using the alignment patterns refers to feedback compensation exposure using OVL measurement results, which is well known to those skilled in the art, and is not described herein again.
The above embodiment takes the case where the first photomask a and the second photomask B are butted right and left as an example, and it should be understood that the above method can also be used in the case where the first photomask a and the second photomask B are butted up and down. The arrangement of the pattern size regions, opaque regions, transparent regions and alignment patterns is similar to the above embodiments, and will not be described herein again.
Example two
Referring to fig. 3, a third alignment pattern including a first front and rear layer alignment pattern 3813 and a second front and rear layer alignment pattern 3814 is further disposed in the first photomask a, the first front and rear layer alignment pattern 3813 and the second front and rear layer alignment pattern 3814 are disposed in the first light transmission region 351, and the third light transmission region 371 includes two front and rear layer alignment patterns also disposed at positions symmetrical to the first front and rear layer alignment pattern 3813 and the second front and rear layer alignment pattern 3814. I.e. the third alignment pattern may comprise 4 front and back layer alignment patterns. The second photomask B is further provided with a sixth alignment pattern, which includes a third front-back layer alignment pattern 3823 and a fourth front-back layer alignment pattern 3824, where the third front-back layer alignment pattern 3823 and the fourth front-back layer alignment pattern 3824 are disposed in the fourth light-transmitting region 352, and two front-back layer alignment patterns that are also disposed in the sixth light-transmitting region 372 and are symmetrical to the third front-back layer alignment pattern 3823 and the fourth front-back layer alignment pattern 3824. I.e. the sixth alignment pattern may comprise 4 front and back layer alignment patterns. The third alignment pattern and the sixth alignment pattern may include more, i.e., not less than 4 front and rear layer alignment patterns, which are used for an alignment process in exposure of the dual photomask in the front and rear layers.
Specifically, the third alignment pattern and the sixth alignment pattern include one or a combination of Bar in Bar, Box in Box, AIM, uDBO, and the like OVL measurement patterns, and the alignment process using the alignment patterns refers to feedback compensation exposure using OVL measurement results, which is well known to those skilled in the art, and is not described herein again.
Referring to fig. 7, fig. 7a) is an exposure effective pattern formed by exposure of the front layer photomask, which includes at least two identical complete exposure effective patterns, and the complete exposure effective patterns are exposure effective patterns formed by combination during exposure of the double photomasks, which may be exposure effective patterns formed by combination as shown in fig. 5. Fig. 7b) shows an exposure effective pattern formed when the photomask is exposed, which also includes at least two identical complete exposure effective patterns, and which may have different pattern shapes from the previous exposure effective pattern shown in fig. 7a), and the rest of the exposure effective pattern is substantially the same as the previous exposure effective pattern shown in fig. 7 a). Referring to fig. 8, when the current-layer dual photomask and the front-layer dual photomask are stacked, the front-layer photomask and the third alignment pattern or the sixth alignment pattern in each of the photomask a and the photomask B in the current-layer photomask provide an alignment pattern, thereby ensuring that an exposure process can be performed using the alignment patterns when the current-layer dual photomask is exposed.
EXAMPLE III
The present invention also provides an exposure method, as shown in fig. 9, the exposure method is a method of performing exposure by using the dual photomask according to the first embodiment or the second embodiment, and the exposure method includes the following steps:
s1: arranging a first photomask A above the wafer coated with the photoresist;
s2: carrying out first exposure to obtain a plurality of first exposure effective patterns corresponding to a first photomask A on a wafer, wherein gaps exist among the first exposure effective patterns, and the size of each gap corresponds to the size of a corresponding second exposure effective pattern formed by exposure of a second photomask B;
s3: arranging a second photomask B above the wafer coated with the photoresist;
s4: carrying out second exposure to obtain a plurality of second exposure effective patterns corresponding to a second photomask B on the wafer, wherein the second exposure effective patterns are positioned in gaps among the first exposure effective patterns, and carrying out an exposure process by utilizing a plurality of alignment patterns;
wherein, the first exposure effective pattern and the second exposure effective pattern are combined to form a complete exposure effective pattern; the size of the complete exposure effective pattern is larger than 26mmx33 mm.
Specifically, the gap is set according to the size of the second photomask B in the exposure process.
Specifically, the alignment patterns include one or a combination of OVL measurement patterns such as Bar in Bar, Box in Box, AIM, and uDBO, and the performing of the exposure process using the alignment patterns refers to feedback compensation exposure using OVL measurement results, which is well known to those skilled in the art, and is not described herein again.
The foregoing embodiments are merely illustrative of the principles of this invention and its efficacy, rather than limiting it, and various modifications and variations can be made by those skilled in the art without departing from the spirit and scope of the invention, which is defined in the appended claims.
Claims (13)
1. A dual photomask comprising a first photomask and a second photomask,
the first photomask includes:
a first opaque region;
a first partial graphic shape; and
a plurality of alignment patterns;
the second photomask includes:
a second opaque region;
a second partial graphical shape; and
a plurality of alignment patterns;
wherein, the first part of the figure shape and the second part of the figure shape are buckled to form a complete figure shape;
the first light-tight area is positioned on one side of the first photomask close to the second photomask;
the second light-tight area is positioned on one side of the second photomask close to the first photomask.
2. A dual photomask as claimed in claim 1, wherein the plurality of alignment patterns of the first photomask comprise:
a first alignment pattern, a second alignment pattern, and a third alignment pattern;
the plurality of alignment patterns of the second photomask include: a fourth alignment pattern, a fifth alignment pattern, and a sixth alignment pattern;
wherein the first alignment pattern and the fourth alignment pattern are used for left-right registration calculation alignment when the first photomask and the second photomask are registered, the second alignment pattern and the fifth alignment pattern are used for left-right registration calculation alignment when the two photomasks are repeatedly registered, and the third alignment pattern and the sixth alignment pattern are used for calculation alignment when the two photomasks of a layer are laminated with the two photomasks of a front layer.
3. A dual photomask according to claim 2,
the first alignment pattern comprises at least 4 current-layer buckling calculation alignment patterns and is positioned on the upper side and the lower side of the first photomask;
the fourth alignment pattern comprises at least 4 current-layer buckling calculation alignment patterns and is positioned on the upper side and the lower side of the second photomask;
the second alignment pattern comprises at least 2 current-layer buckling calculation alignment patterns and is positioned on the left side of the first photomask;
the fifth alignment pattern comprises at least 2 current-layer buckling calculation alignment patterns and is positioned on the right side of the second photomask;
the third alignment pattern comprises at least 4 front-back laminated alignment calculation alignment patterns and is positioned on the upper side and the lower side of the first photomask;
the sixth alignment pattern includes at least 4 front-to-back overlay calculation alignment patterns and is located on upper and lower sides of the second photomask.
4. A dual photomask according to claim 1,
the plurality of alignment patterns of the first photomask include: a first alignment pattern, a second alignment pattern, and a third alignment pattern;
the plurality of alignment patterns of the second photomask include: a fourth alignment pattern, a fifth alignment pattern, and a sixth alignment pattern;
wherein the first alignment pattern and the fourth alignment pattern are used for up-down registration calculation alignment when the first photomask and the second photomask are registered, the second alignment pattern and the fifth alignment pattern are used for up-down registration calculation alignment when the double photomasks are repeatedly registered, and the third alignment pattern and the sixth alignment pattern are used for calculation alignment when the double photomasks on the layer are laminated with the double photomasks on the front layer.
5. A dual photomask according to claim 4,
the first alignment patterns are positioned on the left side and the right side of the first photomask and comprise at least 4 current-layer buckling calculation alignment patterns;
the fourth alignment patterns are positioned on the left side and the right side of the second photomask and comprise at least 4 current-layer buckling calculation alignment patterns; the second alignment pattern is positioned on the lower side of the first photomask and comprises at least 2 current-layer buckling calculation alignment patterns;
the fifth alignment pattern is positioned on the upper side of the second photomask and comprises at least 2 current-layer buckling calculation alignment patterns; the third alignment patterns are positioned on the left side and the right side of the first photomask and comprise at least 4 front-back stacking alignment calculation patterns;
the sixth alignment patterns are located on the left and right sides of the second photomask and include at least 4 front-to-back overlay calculation alignment patterns.
6. A dual photomask according to any one of claims 1 to 5, wherein the size of an exposure effective pattern formed by the dual photomask is greater than 26mmx33 mm.
7. A dual photomask according to any of claims 1 to 5, wherein the first partial pattern shape and the second partial pattern shape have different sizes.
8. A dual photomask according to any of claims 1 to 5, wherein the first opaque region and the second opaque region are covered with a chromium film.
9. A dual photomask according to any of claims 1 through 5,
the first photomask comprises a first light-transmitting substrate, a first graph size area is arranged in the center of the first light-transmitting substrate, a first opaque area is arranged on one side, close to the second photomask, of the first graph size area, and light-transmitting areas I are formed on the other three sides of the first graph size area;
the second photomask comprises a second light-transmitting substrate, a second graph size area is arranged in the center of the second light-transmitting substrate, a second light-tight area is arranged on one side, close to the first photomask, of the second graph size area, and light-transmitting areas II are formed on the other three sides of the second graph size area.
10. A dual photomask according to claim 9,
the maximum width of the first light-transmitting substrate is 104mm, the maximum length of the first light-transmitting substrate is 132mm, the maximum width of the first light-impermeable area is 2.5mm, and the maximum width of the first light-transmitting area is 2.5 mm;
the maximum width of the second light-transmitting substrate is 104mm, the maximum length of the second light-transmitting substrate is 132mm, the maximum width of the second light-impermeable area is 2.5mm, and the maximum width of the second light-transmitting area is 2.5 mm.
11. A dual photomask as claimed in claim 9, wherein the alignment patterns of the first photomask are disposed in the first light-transmitting region and the alignment patterns of the second photomask are disposed in the second light-transmitting region.
12. A dual photomask as defined in claim 9, wherein the first partial pattern shape is formed in the first pattern size area and the second partial pattern shape is formed in the second pattern size area.
13. An exposure method, wherein the exposure method is a method of performing exposure using the dual photomask according to any one of claims 1 to 12, the exposure method comprising the steps of:
s1: arranging the first photomask above the wafer coated with the photoresist;
s2: carrying out first exposure to obtain a plurality of first exposure effective graphs corresponding to the first photomask on the wafer, wherein gaps exist among the first exposure effective graphs, and the size of each gap corresponds to the size of a corresponding second exposure effective graph formed by exposure of the second photomask;
s3: arranging the second photomask above the wafer;
s4: performing a second exposure to obtain a plurality of second exposure effective patterns corresponding to the second photomask on the wafer, wherein the second exposure effective patterns are positioned between the first exposure effective patterns, and performing an exposure process by using a plurality of alignment patterns;
wherein, the first exposure effective pattern and the second exposure effective pattern are combined to form a complete exposure effective pattern; the size of the complete exposure effective pattern is larger than 26mmx33 mm.
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| CN201811134790.7A CN110967920A (en) | 2018-09-28 | 2018-09-28 | Double photomask and exposure method |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201811134790.7A CN110967920A (en) | 2018-09-28 | 2018-09-28 | Double photomask and exposure method |
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| CN110967920A true CN110967920A (en) | 2020-04-07 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117406546A (en) * | 2023-12-14 | 2024-01-16 | 合肥晶合集成电路股份有限公司 | Mask plate and pattern correction method thereof |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06244077A (en) * | 1993-02-19 | 1994-09-02 | Nikon Corp | Exposure device |
| CN1524202A (en) * | 2001-08-27 | 2004-08-25 | 三星电子株式会社 | Exposure mask for fabricating liquid crystal display and method for exposing substrate in fabricating liquid crystal display using the mask |
| CN201974632U (en) * | 2011-04-12 | 2011-09-14 | 京东方科技集团股份有限公司 | Masking film plate and masking film plate module |
| CN103744214A (en) * | 2013-12-31 | 2014-04-23 | 深圳市华星光电技术有限公司 | Exposure method of glass substrate of LCD (Liquid Crystal Display) |
| US20160334674A1 (en) * | 2015-05-15 | 2016-11-17 | Boe Technology Group Co., Ltd. | Alignment Exposure Method and Method of Fabricating Display Substrate |
-
2018
- 2018-09-28 CN CN201811134790.7A patent/CN110967920A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06244077A (en) * | 1993-02-19 | 1994-09-02 | Nikon Corp | Exposure device |
| CN1524202A (en) * | 2001-08-27 | 2004-08-25 | 三星电子株式会社 | Exposure mask for fabricating liquid crystal display and method for exposing substrate in fabricating liquid crystal display using the mask |
| CN201974632U (en) * | 2011-04-12 | 2011-09-14 | 京东方科技集团股份有限公司 | Masking film plate and masking film plate module |
| CN103744214A (en) * | 2013-12-31 | 2014-04-23 | 深圳市华星光电技术有限公司 | Exposure method of glass substrate of LCD (Liquid Crystal Display) |
| US20160334674A1 (en) * | 2015-05-15 | 2016-11-17 | Boe Technology Group Co., Ltd. | Alignment Exposure Method and Method of Fabricating Display Substrate |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117406546A (en) * | 2023-12-14 | 2024-01-16 | 合肥晶合集成电路股份有限公司 | Mask plate and pattern correction method thereof |
| CN117406546B (en) * | 2023-12-14 | 2024-04-12 | 合肥晶合集成电路股份有限公司 | Mask plate and pattern correction method thereof |
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