KR19980036299A - X-ray mask and manufacturing method thereof - Google Patents

Abstract

The present invention relates to an alignment mark pattern formed in an alignment window portion for aligning an X-ray mask and a wafer in an X-ray mask including an alignment window and a main chip window. An X-ray mask and a method of manufacturing the same are described, which are formed on the mask back side as well as the mask front side to optimize the alignment signal.

Description

X-ray mask and manufacturing method thereof

The present invention relates to an X-ray mask and a method of manufacturing the same, and in particular, an alignment mark pattern of an alignment window for aligning an X-ray mask with a wafer is formed on the mask back side as well as on the front side of the mask. The present invention relates to an X-ray mask capable of optimizing an alignment signal and a method of manufacturing the same.

General process steps for forming a chip pattern on a wafer include providing a mask on which a wafer and a chip pattern are designed; Positioning the wafer and the mask in the exposure apparatus, respectively, and then transferring the chip pattern image of the mask to the wafer through an exposure process; A chip pattern is formed on a wafer through a developing process and an etching process.

In the process for forming the chip pattern on the wafer, the degree of alignment with the pattern previously formed on the wafer determines the reliability of the device. If the interlayer alignment is bad, there is a problem that the device malfunctions due to the electrical short circuit and disconnection. One of the factors that prevent the interlayer alignment is when the alignment between the wafer and the mask is not correct in the exposure apparatus. To align the wafer and the mask, an alignment mark pattern is inserted into the mask and the wafer and mask are aligned by sensing an alignment signal during the X-ray lithography process.

As described above, the configuration of the mask for aligning the wafer and the mask using the alignment mark pattern and the problems thereof will be described with reference to FIGS. 1 and 2.

1 is a plan view of a general X-ray mask, Figure 2 is a cross-sectional view taken along the line AA 'of FIG. In the structure in which the silicon layer 2 and the silicon nitride layer 3 are stacked on one side of the X-ray transmissive body 1, selected portions of the silicon nitride layer 3 and the silicon layer 2 are etched. One main chip window 7A and three alignment windows 6A are formed around the main chip window 7A. Except for the alignment window 6A and the main chip window 7A, the portion where the X-ray transmissive body 1, the silicon layer 2 and the silicon nitride layer 3 are stacked is an X-ray non-transmissive region 9A. to be. An adhesive layer 4 and a seed layer 5 are sequentially formed on the other side of the X-ray transparent body 1 so that the X-ray transparent body 1, the adhesive layer 4 and the seed are formed. The layer 5 forms a membrane 10. The membrane 10 has a total thickness of about 2 μm, and the X-ray penetrating member 1 formed of silicon nitride that transmits X-rays well occupies most of the thickness, and the adhesive layer 4 is about 0.01 μm, The seed layer 5 is extremely thin, about 0.02 μm. The X-ray transmittance of the membrane 10 should be at least 50%, and the optical properties of the membrane 10 have a great influence on the interlayer alignment of the wafer, so the transmittance in the visible light region, which is alignment light, should be maintained at 70% or more. There should also be no deformation of the material due to X-ray exposure. A plurality of alignment mark patterns 6 are formed in the seed layer 5 of the alignment window 6A, and a main chip pattern 7 is formed in the seed layer 5 of the main chip window 7A. The adhesive layer 4 is formed of chromium (Cr) so that the seed layer 5 adheres well to the X-ray transmitting body 1. The seed layer 5 is the same as the material forming the alignment mark pattern 6 and the main chip pattern 7, and the alignment mark pattern 6 and the main chip pattern 7 absorb gold well (Au). Is formed. Thereafter, a pyrex ring 8 is formed on the silicon nitride layer 3 to complete the manufacture of the general X-ray mask 100.

The portion where the alignment mark pattern 6 and the main chip pattern 7 are formed is the mask front face 11, and the portion where the alignment window 6A and the main chip window 7A are formed is the mask back surface 12. The Pyrex ring 8 serves as a mechanically strong support.

As described above, in the general X-ray mask 100 including the main chip window 7A and the alignment window 6A formed around the main chip window 7A, the alignment mark pattern 6 has the front face 11 of the mask. Only formed. However, in aligning the wafer and the mask by sensing the alignment signal during the X-ray lithography process, an excellent interlayer alignment degree can be obtained only when the alignment signal is well detected, as shown in FIG. 10C. Interference occurs between the front and rear surfaces of the membrane 10, and the light intensity is weak, so that alignment signals are not excellent.

The present invention, in order to solve the above disadvantages, the alignment mark pattern of the alignment window for aligning the X-ray mask and the wafer is formed not only on the front of the mask but also on the back of the mask to optimize the alignment signal and The purpose is to provide a method for producing the same.

The X-ray mask of the present invention for achieving this object is a membrane; A main chip window and a plurality of alignment windows respectively formed by etching selected portions of the silicon layer and the silicon nitride layer stacked on one side of the membrane; An X-ray non-transmissive region in which the membrane, the silicon layer, and the silicon nitride layer are excepted the alignment window and the main chip window portion; First and second alignment mark patterns formed at both sides of the membrane at the alignment window portion; It consists of a Pyrex ring formed at the edge of the X-ray non-transmissive region.

In addition, the method of manufacturing an X-ray mask of the present invention comprises the steps of providing a structure in which a silicon layer and a silicon nitride layer laminated on one side of the X-ray transmissive body; Etching the silicon nitride layer and the selected portion of the silicon layer to form a main chip window and a plurality of alignment windows, and a portion except the main chip window and the plurality of alignment window portions is an X-ray non-transmissive region ; A first adhesive layer and a first seed layer are sequentially formed on the other side of the X-ray transmissive body, thereby forming a membrane of the X-ray transmissive body, the first adhesive layer and the first seed layer. Becoming; Sequentially forming a second adhesive layer and a second seed layer on the X-ray transmissive body exposed at the alignment window portion; After applying the resist on both sides of the membrane, selectively exposing the resist using an electron beam; Removing the selected portion of the selectively exposed resist; Forming a first and a second alignment mark pattern and a main chip pattern on the first and second seed layers exposed to the portions from which the resist is removed; And after removing the resist, forming a Pyrex ring on the silicon nitride layer in the X-ray non-transmissive region.

1 is a plan view of a typical X-ray mask,

FIG. 2 is a cross-sectional view taken along line AA ′ of FIG. 1;

3 is a plan view of an X-ray mask according to the present invention,

4 is a cross-sectional view taken along the line AA ′ of FIG. 3;

5A to 5D are cross-sectional views for explaining the manufacturing method of the X-ray mask according to the first embodiment of the present invention;

6A to 6H are cross-sectional views for explaining the manufacturing method of the X-ray mask according to the second embodiment of the present invention;

7A to 7C are cross-sectional views for explaining the manufacturing method of the X-ray mask according to the third embodiment of the present invention;

8A to 8C are cross-sectional views for explaining the manufacturing method of the X-ray mask according to the fourth embodiment of the present invention;

9 shows a wafer and an X-ray mask placed in an X-ray lithography exposure apparatus,

10A and 10B show the alignment and the rows of structures of the X-ray mask according to the present invention;

10C shows the alignment and rows of a typical X-ray mask,

11 is a graph comparing the alignment signal of the general X-ray mask with the alignment signal of the X-ray mask of the present invention.

* Description of the symbols for the main parts of the drawings *

1 and 21: X-ray transmission body 2 and 22: silicon layer

3 and 23: silicon nitride layer 4, 24 and 124: adhesive layer

5, 25 and 125: seed layers 6 and 26: alignment mark pattern

6A and 26A: Alignment Windows 7 and 27: Main Chip Pattern

7A and 27A: main chip Windows 8 and 28: Pyrex ring

9A and 29A: X-ray non-transmissive zones 10 and 20: membrane

11 and 31: mask front 12 and 32: mask back

126: Secondary alignment mark pattern 100 and 200: X-ray mask

110 and 120: positive or negative resist

130: negative resist 140 and 150: positive resist

300: alignment microscope 400: wafer

500: light intensity of a typical X-ray mask

600: first light intensity of the X-ray mask of the present invention

700: second light intensity of the X-ray mask of the present invention

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

3 is a plan view of the X-ray mask according to the present invention, Figure 4 is a cross-sectional view taken along the line AA 'of FIG. The X-ray mask 200 of the present invention comprises a membrane 20 for transmitting X-rays; A main chip window 27A and a plurality of alignment windows 26A respectively formed by etching selected portions of the silicon layer 22 and the silicon nitride layer 23 stacked on one side of the membrane 20; An X-ray non-transmissive region 29A in which the membrane 20, the silicon layer 22, and the silicon nitride layer 23 are laminated except for the alignment window 26A and the main chip window 27A portion; A main chip pattern 27 formed at a part of the main chip window 27A; First and second alignment mark patterns 26 and 126 formed at both sides of the membrane 20 at the portion of the alignment window 26A; It consists of a Pyrex ring 20 formed at the edge portion of the X-ray non-transmissive region 29A.

A method of manufacturing the X-ray mask 200 having the above structure will be described with reference to FIGS. 5A to 5D, 6A to 6H, 7A to 7C, and 8A to 8C.

[First Embodiment]

5A to 5D are cross-sectional views for explaining the manufacturing method of the X-ray mask according to the first embodiment of the present invention.

Referring to FIG. 5A, in the structure in which the silicon layer 22 and the silicon nitride layer 23 are stacked on one side of the X-ray transmissive body 21, the silicon nitride layer 23 and the silicon layer 22 are formed. The selected portion of is etched to form a main chip window 27A and a plurality of alignment windows 26A. The first adhesive layer 24 and the first seed layer 25 are sequentially formed on the other side of the X-ray transmissive body 21 so that the X-ray transmissive body 21, the first adhesive layer 24 and the first adhesive layer 24 are sequentially formed. A membrane 20 of one seed layer 25 is formed. The second adhesive layer 124 and the second seed layer 125 are sequentially formed on the X-ray transmissive body 21 exposed to the alignment window 26A. Except for the alignment window 26A and the main chip window 27A, the portion where the X-ray transmissive body 21, the silicon layer 22, and the silicon nitride layer 23 are stacked is an X-ray non-transmissive region 29A. to be. The portion where the first seed layer 25 is formed becomes the X-ray mask front surface 31, and the portion where the alignment window 26A and the main chip window 27A are formed becomes the X-ray mask rear surface 32. At least three alignment windows 26A are formed around the main chip window 27A.

In the above, the membrane 20 has a total thickness of about 2 μm, and has a low atomic number and good strength for transmitting X-rays, for example, silicon nitride (SiN), silicon carbide (SiC), and silicon (Si). , The X-ray transparent body 21 formed of any one of diamonds occupies most of the thickness, the first adhesive layer 24 is 0.005 to 0.01 μm, and the first seed layer 25 is 0.01 to 0.02 μm. It is thin thickness. The X-ray transmittance of the membrane 20 should be 50% or more, and the optical properties of the membrane 20 have a great influence on the interlayer alignment of the wafer, so the transmittance in the visible light region, which is alignment light, should be maintained at 70% or more. There should also be no deformation of the material due to X-ray exposure. Meanwhile, like the first adhesive layer 24, the second adhesive layer 124 is 0.005 to 0.01 μm thick, and the second seed layer 125 is extremely thin, 0.01 to 0.02 μm, similarly to the first seed layer 25. Thickness. The first and second adhesive layers 24 and 124 are formed of chromium so that each of the first and second seed layers 25 and 125 adheres well to the X-ray transmissive body 21. The first and second seed layers 25 and 125 are formed of the same material as the material of the first and second alignment mark patterns and the main chip pattern to be formed later.

5B shows the application of a resist 110 on both sides of the membrane 20, followed by exposure of the electron beam to the mask front side 31. The electron beam selectively exposes the resist 110 of the mask front side 31, with electrons penetrating to the back side of the membrane 20 of the alignment window 26A and the main chip window 27A and applied to the mask back side 32. Resist 110 may also be selectively exposed.

In the above, the resist 110 is positive or negative.

5C shows that the selectively exposed resist 110 is removed from the selected portion through a development process.

5D shows that the first and second alignment mark patterns 26 and 126 and the main chip pattern 27 are deposited through the deposition process on the first and second seed layers 25 and 125 exposed to the portions where the resist 110 is removed. What is formed is shown.

The first and second alignment mark patterns 26 and 126 and the main chip pattern 27 are materials having a large atomic number that absorbs X-rays well and are easy to deposit, pattern, and control stress, for example, gold ( Au), tungsten (W), and tantalum (Ta), optionally as described above, for the first and second seed layers 25 and 125 formed of the same material as these patterns 26, 126, and 27. Is deposited and formed. The first alignment mark pattern 26 is formed in the alignment window 26A portion of the mask front surface 31, and the second alignment mark pattern 126 is formed in the alignment window 26A portion of the mask rear surface 32. The first and second alignment mark patterns 26 and 126 are located on the same line. The main chip pattern 27 is formed in the main chip window 27A portion of the mask front surface 31, and there is no seed layer in the main chip window 27A portion of the mask rear surface 32 so that no pattern is formed.

Then, the resist 110 in front of and behind the masks 31 and 32 is removed, and a Pyrex ring 28 is formed on the silicon nitride layer 23 to form the X-ray mask of the present invention shown in FIG. 200) Manufacturing is complete. The Pyrex ring 28 is formed along the edge of the X-ray mask backside 32, which serves as a mechanically strong support.

Second Embodiment

6A to 6H are cross-sectional views for explaining the manufacturing method of the X-ray mask according to the second embodiment of the present invention.

Referring to FIG. 6A, in the structure in which the silicon layer 22 and the silicon nitride layer 23 are stacked on one side of the X-ray transmissive body 21, the silicon nitride layer 23 and the silicon layer 22 are formed. The selected portion of is etched to form a main chip window 27A and a plurality of alignment windows 26A. The first adhesive layer 24 and the first seed layer 25 are sequentially formed on the other side of the X-ray transmissive body 21 so that the X-ray transmissive body 21, the first adhesive layer 24 and the first adhesive layer 24 are sequentially formed. A membrane 20 of one seed layer 25 is formed. Except for the alignment window 26A and the main chip window 27A, the portion where the X-ray transmissive body 21, the silicon layer 22, and the silicon nitride layer 23 are stacked is an X-ray non-transmissive region 29A. to be. The portion where the first seed layer 25 is formed becomes the X-ray mask front surface 31, and the portion where the alignment window 26A and the main chip window 27A are formed becomes the X-ray mask rear surface 32. At least three alignment windows 26A are formed around the main chip window 27A.

In the above, the membrane 20 has a total thickness of about 2 μm, and has a low atomic number and good strength for transmitting X-rays, for example, silicon nitride (SiN), silicon carbide (SiC), and silicon (Si). , The X-ray transparent body 21 formed of any one of diamonds occupies most of the thickness, the first adhesive layer 24 is 0.005 to 0.01 μm, and the first seed layer 25 is 0.01 to 0.02 μm. It is thin thickness. The X-ray transmittance of the membrane 20 should be 50% or more, and the optical properties of the membrane 20 have a great influence on the interlayer alignment of the wafer, so the transmittance in the visible light region, which is alignment light, should be maintained at 70% or more. There should also be no deformation of the material due to X-ray exposure. The first adhesive layer 24 is formed of chromium so that the first seed layer 25 adheres well to the X-ray transmissive body 21. The first seed layer 25 is formed of the same material as the material of the first alignment mark pattern and the main chip pattern to be formed later.

FIG. 6B shows the application of the first resist 120 on the first seed layer 25 of the mask front face 31, followed by the exposure of the electron beam to the mask front face 31. The electron beam selectively exposes the applied first resist 120.

In the above, the first resist 120 is positive or negative.

6C shows that the selectively exposed first resist 120 is removed from the selected portion through a development process.

FIG. 6D shows that the first alignment mark pattern 26 and the main chip pattern 27 are formed in the first seed layer 25 exposed to the portion where the first resist 120 is removed through the deposition process.

The first alignment mark pattern 26 and the main chip pattern 27 are materials having a large atomic number that absorbs X-rays well and are easy to deposit, pattern, and control stress, for example, gold (Au) and tungsten. (W) and tantalum (Ta), which are selectively deposited on the first seed layer 25 formed of the same material as those of the patterns 26 and 27 as described above. The first alignment mark pattern 26 is formed in the alignment window 26A portion of the mask front surface 31. The main chip pattern 27 is formed in the main chip window 27A portion of the mask front surface 31.

The process described with reference to FIGS. 6A through 6D is the same as the general X-ray mask 100 manufacturing process shown in FIG. 1.

6E shows that after the first resist 120 is removed, the second adhesive layer 124 and the second seed layer 125 are sequentially disposed on the X-ray transmissive body 21 exposed to the alignment window 26A. What is formed is shown.

In the above description, the second adhesive layer 124 has a thickness of 0.005 to 0.01 μm similarly to the first adhesive layer 24, and the second seed layer 125 is extremely low to 0.01 to 0.02 μm similarly to the first seed layer 25. It is thin thickness. The second adhesive layer 124 is formed of chromium so that the second seed layer 125 adheres well to the X-ray transmissive body 21. The second seed layer 125 is formed of the same material as the material of the second alignment mark pattern to be formed later.

6F shows the application of the second resist 130 to the mask backside 32 followed by exposure of UV or X-rays to the mask frontside 31. The second resist 130 is negative and is self-exposed by the first alignment mark pattern 26 and the main chip pattern 27.

6G shows that the unexposed portions of second resist 130 are removed through a development process.

FIG. 6H shows that a second alignment mark pattern 126 is formed through a deposition process on the second seed layer 125 where the second resist 130 is removed.

The second alignment mark pattern 126 is a material having a large atomic number that absorbs X-rays well and is easy to deposit, pattern, and control stress, for example, gold (Au), tungsten (W), and tantalum (Ta). As described above, it is selectively deposited on the second seed layer 125 formed of the same material as the pattern 126. The second alignment mark pattern 126 is formed in the alignment window 26A portion of the mask back surface 32. The second alignment mark pattern 126 is positioned on the same line as the first alignment mark pattern 26. Since the seed layer is not present in the main chip window 27A portion of the mask rear surface 32, no pattern is formed.

Thereafter, the second resist 130 of the mask back surface 32 is removed, and the Pyrex ring 28 is formed on the silicon nitride layer 23 to form the X-ray mask 200 of the present invention shown in FIG. 4. Manufacturing is complete. The Pyrex ring 28 is formed along the edge of the X-ray mask backside 32, which serves as a mechanically strong support.

Third Embodiment

7A to 7C are cross-sectional views for explaining the manufacturing method of the X-ray mask according to the third embodiment of the present invention.

Referring to FIG. 7A, in the structure in which the silicon layer 22 and the silicon nitride layer 23 are stacked on one side of the X-ray transmissive body 21, the silicon nitride layer 23 and the silicon layer 22 are formed. The selected portion of is etched to form a main chip window 27A and a plurality of alignment windows 26A. The first adhesive layer 24 and the first seed layer 25 are sequentially formed on the other side of the X-ray transmissive body 21 so that the X-ray transmissive body 21, the first adhesive layer 24 and the first adhesive layer 24 are sequentially formed. A membrane 20 of one seed layer 25 is formed. Except for the alignment window 26A and the main chip window 27A, the portion where the X-ray transmissive body 21, the silicon layer 22, and the silicon nitride layer 23 are stacked is an X-ray non-transmissive region 29A. to be. The portion where the first seed layer 25 is formed becomes the X-ray mask front surface 31, and the portion where the alignment window 26A and the main chip window 27A are formed becomes the X-ray mask rear surface 32. At least three alignment windows 26A are formed around the main chip window 27A. The first alignment mark pattern 26 and the main chip pattern 27 are formed on the first seed layer 25 through an electron beam lithography process and a deposition process (see the above-described process steps in FIGS. 6A to 6D). The second adhesive layer 124 and the second seed layer 125 are sequentially formed on the X-ray transmissive body 21 exposed to the alignment window 26A.

In the above, the membrane 20 has a total thickness of about 2 μm, and has a low atomic number and good strength for transmitting X-rays, for example, silicon nitride (SiN), silicon carbide (SiC), and silicon (Si). , The X-ray transparent body 21 formed of any one of diamonds occupies most of the thickness, the first adhesive layer 24 is 0.005 to 0.01 μm, and the first seed layer 25 is 0.01 to 0.02 μm. It is thin thickness. The X-ray transmittance of the membrane 20 should be 50% or more, and the optical properties of the membrane 20 have a great influence on the interlayer alignment of the wafer, so the transmittance in the visible light region, which is alignment light, should be maintained at 70% or more. There should also be no deformation of the material due to X-ray exposure. Meanwhile, like the first adhesive layer 24, the second adhesive layer 124 is 0.005 to 0.01 μm thick, and the second seed layer 125 is extremely thin, 0.01 to 0.02 μm, similarly to the first seed layer 25. Thickness. The first and second adhesive layers 24 and 124 are formed of chromium so that each of the first and second seed layers 25 and 125 adheres well to the X-ray transmissive body 21. The first seed layer 25 is formed of the same material as that of the first alignment mark pattern and the main chip patterns 26 and 27, and the first alignment mark pattern 26 and the main chip pattern 27 are X-rays. It is a material having a large atomic number that absorbs well and is easy to deposit, pattern formation and stress control, for example, gold (Au), tungsten (W), tantalum (Ta), these patterns 26 and 27 Is selectively deposited on the first seed layer 25 formed of the same material as The second seed layer 125 is formed of the same material as the first seed layer 25. The first alignment mark pattern 26 is formed in the alignment window 26A portion of the mask front surface 31. The main chip pattern 27 is formed in the main chip window 27A portion of the mask front surface 31.

FIG. 7B shows that after the positive resist 140 is selectively applied to the alignment window 26A portion and the main chip window 27A of the mask back surface 32, the UV or X-rays are exposed to the mask front surface 31. Shown. During the exposure process, the first alignment mark pattern 26 and the main chip pattern 27 serve as masks to selectively expose the positive resist 140.

7C shows that the exposed portion of the positive resist 140 is removed through a development process to form a second alignment mark pattern 126 of positive resist.

The second alignment mark pattern 126 is positioned on the same line as the first alignment mark pattern 26 and the main chip pattern 27.

Thereafter, a Pyrex ring 28 is formed on the silicon nitride layer 23 to complete the manufacture of the X-ray mask 200 of the present invention shown in FIG. The Pyrex ring 28 is formed along the edge of the X-ray mask backside 32, which serves as a mechanically strong support.

[Example 4]

8A to 8C are cross-sectional views for explaining the manufacturing method of the X-ray mask according to the fourth embodiment of the present invention.

Referring to FIG. 8A, in the structure in which the silicon layer 22 and the silicon nitride layer 23 are stacked on one side of the X-ray transmissive body 21, the silicon nitride layer 23 and the silicon layer 22 are formed. The selected portion of is etched to form a main chip window 27A and a plurality of alignment windows 26A. The adhesive layer 24 and the seed layer 25 are sequentially formed on the other side of the X-ray transmissive body 21 to form the X-ray transmissive body 21, the adhesive layer 24 and the seed layer 25. Membrane 20 is formed. Except for the alignment window 26A and the main chip window 27A, the portion where the X-ray transmissive body 21, the silicon layer 22, and the silicon nitride layer 23 are stacked is an X-ray non-transmissive region 29A. to be. The portion where the seed layer 25 is formed becomes the X-ray mask front surface 31, and the portion where the alignment window 26A and the main chip window 27A are formed becomes the X-ray mask rear surface 32. At least three alignment windows 26A are formed around the main chip window 27A. The first alignment mark pattern 26 and the main chip pattern 27 are formed in the seed layer 25 through an electron beam lithography process and a deposition process (see the above-described process steps in FIGS. 6A to 6D).

In the above, the membrane 20 has a total thickness of about 2 μm, and has a low atomic number and good strength for transmitting X-rays, for example, silicon nitride (SiN), silicon carbide (SiC), and silicon (Si). The X-ray transparent body 21 formed of any one of diamonds occupies most of the thickness, the adhesive layer 24 is 0.005 to 0.01 μm, and the seed layer 25 is 0.01 to 0.02 μm, which is extremely thin. The X-ray transmittance of the membrane 20 should be 50% or more, and the optical properties of the membrane 20 have a great influence on the interlayer alignment of the wafer, so the transmittance in the visible light region, which is alignment light, should be maintained at 70% or more. There should also be no deformation of the material due to X-ray exposure. The adhesive layer 24 is formed of chromium so that the seed layer 25 adheres well to the X-ray transmitting body 21. The seed layer 25 is formed of the same material as the material of the first alignment mark pattern and the main chip patterns 26 and 27, and the first alignment mark pattern 26 and the main chip pattern 27 are good at X-rays. A material having a large atomic number that absorbs and which is easy to deposit, form a pattern, and control stress, for example, any one of gold (Au), tungsten (W), and tantalum (Ta). It is formed by selectively depositing on the seed layer 25 formed of the same material. The first alignment mark pattern 26 is formed in the alignment window 26A portion of the mask front surface 31. The main chip pattern 27 is formed in the main chip window 27A portion of the mask front surface 31.

8B shows that after the positive resist 150 is selectively applied to the alignment window 26A and the main chip window 27A portion of the mask back surface 32, the UV or X-rays are exposed to the mask front surface 31. Shown. During the exposure process, the first alignment mark pattern 26 and the main chip pattern 27 serve as masks to selectively expose the positive resist 150.

8C shows that the exposed portion of the positive resist 150 is removed through a development process to form a second alignment mark pattern 126 of positive resist.

The second alignment mark pattern 126 is positioned on the same line as the first alignment mark pattern 26 and the main chip pattern 27.

Thereafter, a Pyrex ring 28 is formed on the silicon nitride layer 23 to complete the manufacture of the X-ray mask 200 of the present invention shown in FIG. The Pyrex ring 28 is formed along the edge of the X-ray mask backside 32, which serves as a mechanically strong support.

9 shows a wafer 400 and an X-ray mask 200 of the present invention disposed in an X-ray lithography exposure apparatus. After placing the wafer 400 and the X-ray mask 200 of the present invention in the exposure apparatus, the X-rays are irradiated to transfer the chip pattern image of the mask 200 to the wafer 400. The irradiated X-rays transmit the chip pattern image to the wafer 400 by passing through the main chip window 27A, and in the alignment window 26A portion, most of the X-rays are membranes as shown in FIGS. 10B and 10C. Reflected by the second alignment mark pattern 126 formed on the back side of the membrane 20 without penetrating 20, the reflected X-rays are sensed by the alignment microscope 300 as an alignment signal. 11 is a graph comparing the alignment signal of the general X-ray mask and the alignment signal of the X-ray mask of the present invention, wherein the optical intensity 500 of the general X-ray mask is very weak, and the X of the present invention is The first and second light intensities 600 and 700 of the -line mask appear very intense. The first light intensity 600 is when the second alignment mark pattern 126 of the mask back surface 32 is formed of a resist, and the second light intensity 700 is the second alignment mark pattern 126 of the mask back surface 32. ) Is a material having a large atomic number that absorbs X-rays, for example, one of gold (Au), tungsten (W), and tantalum (Ta).

As described above, in the X-ray mask composed of the alignment window and the main chip window, the alignment mark pattern formed on the alignment window portion for aligning the X-ray mask and the wafer is formed on the mask back surface as well as the mask front surface. The alignment signal is optimized by maximizing the light intensity reflected by the alignment microscope during the X-ray lithography process.

Thus, the optimized alignment signal can be used to accurately align the X-ray mask with the wafer.

Claims (73)

In the X-ray mask consisting of the alignment window and the main chip window, And an alignment mark pattern formed in the alignment window portion for aligning the X-ray mask and the wafer, respectively, formed on the front side of the mask and the rear side of the mask. The method of claim 1, At least three alignment windows are formed around the main chip window. The method of claim 1, The alignment mark patterns on the front and rear surfaces of the mask are formed of a material having a large atomic number that absorbs X-rays well and easy to deposit, pattern, and control stress. The method of claim 1, Alignment mark patterns on the front and back of the mask is formed of any one of gold (Au), tungsten (W), tantalum (Ta), nickel (Ni), silver (Ag). The method of claim 1, The alignment mark pattern on the back of the mask is characterized in that formed of a resist. The method of claim 5, And the resist is positive. A membrane; A main chip window and a plurality of alignment windows respectively formed by etching selected portions of the silicon layer and the silicon nitride layer stacked on one side of the membrane; An X-ray non-transmissive region in which the membrane, the silicon layer, and the silicon nitride layer are excepted the alignment window and the main chip window portion; A main chip pattern formed on the main chip window portion; First and second alignment mark patterns formed at both sides of the membrane at the alignment window portion; And a Pyrex ring formed at an edge of the X-ray non-transmissive region. The method of claim 7, wherein The membrane is formed by laminating an X-ray transmissive body, an adhesive layer and a seed layer, the thickness of the X-ray mask, characterized in that about 2μm. The method of claim 8, The X-ray transmissive member is an X-ray mask, characterized in that formed of a material having a low atomic number and good strength that transmits X-rays well. The method of claim 8, The X-ray transmissive member is formed of any one of silicon nitride (SiN), silicon carbide (SiC), silicon (Si), and diamond. The method of claim 8, The adhesive layer is formed of any one of chromium (Cr) and titanium (Ti), X-ray mask, characterized in that the thickness of 0.005 to 0.01μm. The method of claim 8, The seed layer is formed of any one of gold (Au), tungsten (W), tantalum (Ta), X-ray mask, characterized in that the thickness of 0.01 to 0.02μm. The method of claim 7, wherein At least three alignment windows are formed around the main chip window. The method of claim 7, wherein And the first alignment mark pattern and the main chip pattern are formed on the front side of the mask, and the second alignment mark pattern is formed on the back side of the mask. The method of claim 7, wherein And the first and second alignment mark patterns and the main chip pattern are formed of a material having a large atomic number that absorbs X-rays well and being easy to deposit, pattern, and control stress. The method of claim 7, wherein And the first and second alignment mark patterns and the main chip pattern are formed of any one of gold (Au), tungsten (W), and tantalum (Ta). The method of claim 7, wherein And the second alignment mark pattern is formed of resist. The method of claim 17, And the resist is positive. In the manufacturing method of the X-ray mask, Providing a structure in which a silicon layer and a silicon nitride layer are stacked on one side of the X-ray transmissive body; Etching the silicon nitride layer and the selected portion of the silicon layer to form a main chip window and a plurality of alignment windows, and a portion except the main chip window and the plurality of alignment window portions is an X-ray non-transmissive region ; A first adhesive layer and a first seed layer are sequentially formed on the other side of the X-ray transmissive body, thereby forming a membrane of the X-ray transmissive body, the first adhesive layer and the first seed layer. Becoming; Sequentially forming a second adhesive layer and a second seed layer on the X-ray transmissive body exposed at the alignment window portion; After applying the resist on both sides of the membrane, selectively exposing the resist using an electron beam; Removing the selected portion of the selectively exposed resist; Forming a first and a second alignment mark pattern and a main chip pattern on the first and second seed layers exposed to the portions from which the resist is removed; And After removing the resist, forming a pyrex ring on the silicon nitride layer in the non-transparent region of the X-rays. The method of claim 19, The membrane is X-ray mask manufacturing method, characterized in that to form a thickness of about 2μm. The method of claim 19, The X-ray transmissive member is a method of manufacturing an X-ray mask, characterized in that formed of a material having a low atomic number and good strength that transmits X-rays well. The method of claim 19, The X-ray transmissive member is formed of any one of silicon nitride (SiN), silicon carbide (SiC), silicon (Si), diamond. The method of claim 19, The first and second pressure-sensitive adhesive layer is formed of chromium, the thickness of the X-ray mask manufacturing method, characterized in that 0.005 to 0.01μm. The method of claim 19, The first and second seed layers are formed of any one of gold (Au), tungsten (W), and tantalum (Ta), and have a thickness of 0.01 to 0.02 μm. The method of claim 19, And at least three alignment windows around the main chip window. The method of claim 19, The first alignment mark pattern is formed on the first seed layer of the alignment window portion, the second alignment mark pattern is formed on the second seed layer of the alignment window portion, and the main chip pattern is the main chip. Forming on the first seed layer of the window portion. The method of claim 19, The first and second alignment mark patterns and the main chip pattern is formed of a material having a large atomic number that absorbs X-rays well and easy to deposit, pattern, and stress control. . The method of claim 19, And the first and second alignment mark patterns and the main chip pattern are formed of any one of gold (Au), tungsten (W), and tantalum (Ta). The method of claim 19, And the first seed layer is the same as a material forming the first alignment mark pattern and the main chip pattern. The method of claim 19, And the second seed layer is the same as the material of forming the second alignment mark pattern. The method of claim 19, And the resist is either positive or negative. In the manufacturing method of the X-ray mask, Providing a structure in which a silicon layer and a silicon nitride layer are stacked on one side of the X-ray transmissive body; Etching the silicon nitride layer and the selected portion of the silicon layer to form a main chip window and a plurality of alignment windows, and a portion except the main chip window and the plurality of alignment window portions is an X-ray non-transmissive region ; A first adhesive layer and a first seed layer are sequentially formed on the other side of the X-ray transmissive body, thereby forming a membrane of the X-ray transmissive body, the first adhesive layer and the first seed layer. Becoming; After applying a first resist on the first seed layer, selectively exposing the first resist using an electron beam; Removing the selected portion of the selectively exposed first resist; Forming a first alignment mark pattern and a main chip pattern on the first seed layer exposed to the portion from which the first resist is removed; After removing the first resist, sequentially forming a second adhesive layer and a second seed layer on the X-ray transmissive body exposed at the alignment window portion; Applying a second resist onto the membrane on the side where the second seed layer is formed, and then exposing the second resist using UV; Removing the unexposed portions of the second resist; Forming a second alignment mark pattern on the second seed layer exposed to the portion from which the second resist is removed; And After removing the second resist, forming a Pyrex ring on the silicon nitride layer in the X-ray non-transmissive region. The method of claim 32, The membrane is X-ray mask manufacturing method, characterized in that to form a thickness of about 2μm. The method of claim 32, The X-ray transmissive member is a method of manufacturing an X-ray mask, characterized in that formed of a material having a low atomic number and good strength that transmits X-rays well. The method of claim 32, The X-ray transmissive member is formed of any one of silicon nitride (SiN), silicon carbide (SiC), silicon (Si), diamond. The method of claim 32, The first and second pressure-sensitive adhesive layer is formed of chromium, the thickness of the X-ray mask manufacturing method, characterized in that 0.005 to 0.01μm. The method of claim 32, The first and second seed layers are formed of any one of gold (Au), tungsten (W), and tantalum (Ta), and have a thickness of 0.01 to 0.02 μm. The method of claim 32, And at least three alignment windows around the main chip window. The method of claim 32, The first alignment mark pattern is formed on the first seed layer of the alignment window portion, the second alignment mark pattern is formed on the second seed layer of the alignment window portion, and the main chip pattern is the main chip. Forming on the first seed layer of the window portion. The method of claim 32, The first and second alignment mark patterns and the main chip pattern is formed of a material having a large atomic number that absorbs X-rays well and easy to deposit, pattern, and stress control. . The method of claim 32, And the first and second alignment mark patterns and the main chip pattern are formed of any one of gold (Au), tungsten (W), and tantalum (Ta). The method of claim 32, And the first seed layer is the same as a material forming the first alignment mark pattern and the main chip pattern. The method of claim 32, And the second seed layer is the same as the material of forming the second alignment mark pattern. The method of claim 32, And the first resist is one of positive and negative. The method of claim 32, And the second resist is self-alignedly exposed by the first alignment mark pattern and the main chip pattern. The method of claim 32 or 45, And wherein said second resist is negative. The method of claim 32, And using X-rays instead of UVs when exposing the second resist. In the manufacturing method of the X-ray mask, Providing a structure in which a silicon layer and a silicon nitride layer are stacked on one side of the X-ray transmissive body; Etching the silicon nitride layer and the selected portion of the silicon layer to form a main chip window and a plurality of alignment windows, and a portion except the main chip window and the plurality of alignment window portions is an X-ray non-transmissive region ; A first adhesive layer and a first seed layer are sequentially formed on the other side of the X-ray transmissive body, thereby forming a membrane of the X-ray transmissive body, the first adhesive layer and the first seed layer. Becoming; Forming a first alignment mark pattern and a main chip pattern on the first seed layer; Sequentially forming a second adhesive layer and a second seed layer on the X-ray transmissive body exposed at the alignment window portion; Selectively applying a positive resist only on the second seed layer exposed in the alignment window portion, and then exposing the positive resist using UV; Removing the exposed portion of the positive resist, thereby forming a second alignment mark pattern of portions in which the positive resist remains; And Forming a pyrex ring on said silicon nitride layer in said non-transmissive region of said X-rays. 49. The method of claim 48 wherein The membrane is X-ray mask manufacturing method, characterized in that to form a thickness of about 2μm. 49. The method of claim 48 wherein The X-ray transmissive member is a method of manufacturing an X-ray mask, characterized in that formed of a material having a low atomic number and good strength that transmits X-rays well. 49. The method of claim 48 wherein The X-ray transmissive member is formed of any one of silicon nitride (SiN), silicon carbide (SiC), silicon (Si), diamond. 49. The method of claim 48 wherein The first and second pressure-sensitive adhesive layer is formed of chromium, the thickness of the X-ray mask manufacturing method, characterized in that 0.005 to 0.01μm. 49. The method of claim 48 wherein The first and second seed layers are formed of any one of gold (Au), tungsten (W), and tantalum (Ta), and have a thickness of 0.01 to 0.02 μm. 49. The method of claim 48 wherein And at least three alignment windows around the main chip window. 49. The method of claim 48 wherein The first alignment mark pattern is formed on the first seed layer of the alignment window portion, and the main chip pattern is formed on the first seed layer of the main chip window portion. . 49. The method of claim 48 wherein And the first alignment mark pattern and the main chip pattern are formed of a material having a large atomic number that absorbs X-rays well and easy to deposit, pattern, and control stress. 49. The method of claim 48 wherein And the first alignment mark pattern and the main chip pattern are formed of any one of gold (Au), tungsten (W), and tantalum (Ta). 49. The method of claim 48 wherein And the first seed layer is the same as a material forming the first alignment mark pattern and the main chip pattern. 49. The method of claim 48 wherein And wherein the positive resist is self-alignedly exposed by the first alignment mark pattern and the main chip pattern. 49. The method of claim 48 wherein Using x-rays instead of UVs in exposing said positive resist. In the manufacturing method of the X-ray mask, Providing a structure in which a silicon layer and a silicon nitride layer are stacked on one side of the X-ray transmissive body; Etching the silicon nitride layer and the selected portion of the silicon layer to form a main chip window and a plurality of alignment windows, and a portion except the main chip window and the plurality of alignment window portions is an X-ray non-transmissive region ; Sequentially forming a pressure-sensitive adhesive layer and a seed layer on the other side of the X-ray transparent body, thereby forming a membrane of the X-ray transparent body, the pressure-sensitive adhesive layer and the seed layer; Forming a first alignment mark pattern and a main chip pattern on the seed layer; Selectively applying a positive resist only on the X-ray transmissive body exposed in the alignment window portion, and then exposing the positive resist using UV; Removing the exposed portion of the positive resist, thereby forming a second alignment mark pattern of portions in which the positive resist remains; And Forming a pyrex ring on said silicon nitride layer in said non-transmissive region of said X-rays. 62. The method of claim 61, The membrane is X-ray mask manufacturing method, characterized in that to form a thickness of about 2μm. 62. The method of claim 61, The X-ray transmissive member is a method of manufacturing an X-ray mask, characterized in that formed of a material having a low atomic number and good strength that transmits X-rays well. 62. The method of claim 61, The X-ray transmissive member is formed of any one of silicon nitride (SiN), silicon carbide (SiC), silicon (Si), diamond. 62. The method of claim 61, The adhesive layer is formed of chromium, the thickness of the X-ray mask manufacturing method, characterized in that 0.005 to 0.01μm. 62. The method of claim 61, The seed layer is formed of any one of gold (Au), tungsten (W), tantalum (Ta), the thickness of the X-ray mask manufacturing method, characterized in that 0.01 to 0.02μm. 62. The method of claim 61, And at least three alignment windows around the main chip window. 62. The method of claim 61, And the first alignment mark pattern is formed on the seed layer of the alignment window portion, and the main chip pattern is formed on the seed layer of the main chip window portion. 62. The method of claim 61, The first and second alignment mark patterns and the main chip pattern is formed of a material having a large atomic number that absorbs X-rays well and easy to deposit, pattern, and stress control. . 62. The method of claim 61, And the first alignment mark pattern and the main chip pattern are formed of any one of gold (Au), tungsten (W), and tantalum (Ta). 62. The method of claim 61, And the seed layer is the same as a material forming the first alignment mark pattern and the main chip pattern. 62. The method of claim 61, And wherein the positive resist is self-alignedly exposed by the first alignment mark pattern and the main chip pattern. 62. The method of claim 61, Using x-rays instead of UVs in exposing said positive resist.