JP2003158058A - Mask, its manufacturing method and method for manufacturing semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mask and its manufacturing method which can transfer a pattern having a large area, without causing displacement and distortion of the pattern, and to provide a method for manufacturing a semiconductor device. SOLUTION: The mask has a first to third complementary masks which contain a first to third thin films, respectively. A hole of the first thin film is formed by a first complementary splitting pattern wherein a transferring pattern selects small regions which are not adjacent from among a plurality of small regions split by splitting lines. A hole of the second thin film is formed by a second complementary splitting pattern wherein small regions which are not adjacent are selected except the first complementary splitting pattern. A hole of the third thin film is formed by a third complementary splitting pattern constituted of small regions which are not adjacent except the first and second complementary splitting patterns. The splitting lines satisfy both a first splitting condition that small regions surrounded by splitting lines are adjacent to an even number of small regions, and a second splitting condition that the number of splitting lines stretching from vertexes of a small region is at most three.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mask used for manufacturing a semiconductor device, a method for manufacturing the same, and a method for manufacturing a semiconductor device.

[0002]

2. Description of the Related Art In recent years, with the miniaturization of semiconductor devices, lithography using electron beams, X-rays, ion beams, etc. has been developed. A stencil mask or a membrane mask is used for these lithography. The stencil mask is a thin film (membrane) made of, for example, silicon and provided with holes. The pattern is transferred by the electron beam passing through the hole.

On the other hand, the membrane mask is one in which, for example, a heavy metal layer is formed in a predetermined pattern on a membrane through which an electron beam or the like passes. Electron beams and the like are scattered by the heavy metal layer and pass through the membrane other than the heavy metal layer. As a result, the pattern is transferred.

As the electron beam transfer type lithography, IB is used.
PREVAIL (projecti jointly developed by M and Nikon
on exposure with vaiable axis immersion lenses)
And SCAL developed by Lucent Technology
PEL (scattering with angular limitation in proj
LEEPL (low en by joint development of ection electron-beam lithography) and Leaple, Tokyo Seimitsu and Sony
ergy electron-beam proximity projection lithograph
y).

A high energy electron beam having an acceleration voltage of about 50 to 100 kV is used for PREVAIL and SCALPEL. In these exposure methods, the electron beam that has passed through a part of the mask is imaged on the resist by a reduction projection system of 4 times in general, and the pattern is transferred. On the other hand, a low energy electron beam with an acceleration voltage of about 2 kV is used for LEEPL. In this exposure method, an electron beam is transmitted through the holes provided in the mask, so that the pattern is transferred to the resist at the same magnification.

Both a stencil mask and a membrane mask can be used for PREVAIL and SCALPEL. On the other hand, in LEEPL, the energy of the electron beam is low and the electron beam does not pass through the membrane other than the holes, so only the stencil mask can be used. Since low-energy electron beams are used for LEEPL, LEEPL
The stencil mask for L has a thinner membrane than the stencil mask used for PREVAIL or the like.

FIG. 19 is a schematic diagram showing exposure by LEEPL. As shown in FIG. 19, when the electron beam 1 a enters the stencil mask 2, the electron beam 1 a is transmitted only through the holes 3 of the stencil mask 2 and the membrane 4 other than the holes 3 is exposed.
Then, the electron beam 1a is blocked. Electron beam 1 transmitted through hole 3
The pattern is transferred when b is incident on the resist previously coated on the wafer. FIG. 20 is a top view of the stencil mask 2 of FIG. As shown in FIG. 20, the membrane 4 is provided with a plurality of holes 3 corresponding to the circuit pattern.

[0008]

Since the stencil mask has holes formed in the membrane itself, the internal stress and mechanical strength of the membrane change depending on the pattern. The thinner the membrane, the more accurately the holes can be formed. However, the thinned membrane is easily bent, and the bending of the membrane causes pattern distortion and displacement. In order to prevent the membrane from bending, the membrane is formed so as to have tensile stress inside.

Although it is possible to give a large tensile internal stress to the membrane, if a hole is formed in the membrane in a state where the internal stress is large, the internal stress is released at the hole portion, and the position shift or distortion of the hole is likely to occur. Further, as described above, since the stencil mask for LEEPL is formed to be particularly thin, the internal stress is locally concentrated at a specific portion of the membrane due to the formation of the holes, and the membrane is formed at the edges of the holes, especially at the corners of the holes. May be damaged.

As shown in FIG. 20, since a plurality of holes 3 having different areas are formed in the membrane 4, the coefficient of thermal expansion of the membrane is not uniform throughout the membrane. Therefore, during lithography, when a charged particle beam such as an electron beam is incident on the stencil mask, the displacement and distortion of the holes may occur due to the variation in the thermal expansion amount in the membrane.

In particular, as shown in FIG. 21, the large-diameter hole 3
When a is formed, the positional deviation and distortion of the holes due to the above factors become remarkable, and it becomes impossible to accurately transfer the pattern in lithography. Therefore, a method has been devised in which a pattern having a large area is divided into a plurality of patterns, the divided patterns are distributed to a plurality of masks, and the patterns are transferred by multiple exposure.

When a stencil mask is used, it is essential to use a complementary mask to transfer a specific pattern. Therefore, as described below, the positional accuracy of the pattern is particularly important. The stencil mask membrane must be continuous at all but the holes.

For example, in the case of a donut-shaped pattern, the pattern cannot be transferred with one mask because the independent central portion is not supported by the mask. Therefore, the patterns are divided to form different complementary division patterns on the two complementary masks. By performing multiple exposure twice using these masks, patterns are complementarily transferred.

Alternatively, in a long line-shaped pattern or a line-and-space (L / S) pattern in which a plurality of line-shaped patterns are arranged in parallel, anisotropic strain is generated around the holes due to the internal stress of the membrane. . This allows
The line width becomes uneven, and the membrane is easily damaged at the corners of the pattern. Therefore, the line-shaped pattern may be divided into a plurality of rectangles so that the difference in length and width may be small, and these may be divided and formed into two complementary masks. By performing multiple exposure using these masks, the linear pattern is transferred complementarily.

When performing multiple exposure using complementary masks,
It is necessary to connect the divided patterns with high accuracy. If the positional displacement and distortion of the patterns differ between complementary masks, the patterns cannot be joined by multiple exposure. Therefore, when performing complementary division, it is necessary to prevent local stress concentration on the membrane in each complementary mask and prevent displacement and distortion of the holes.

A method of complementarily dividing a pattern in a stencil mask and distributing it to two complementary masks is disclosed in Japanese Patent Laid-Open Nos. 3-196040 and 2001-57331. According to the electric circuit layout dividing method described in Japanese Patent Laid-Open No. 3-196040, the multi-sided edge is projected from an apex of a corner (here, an inner angle) that protrudes toward the inside of the polygonal hole and satisfies a specific condition. One of the sides of the shape
Draw a cutting line up to one to divide the hole into sections. A complementary division pattern is formed by alternately allocating the divided sections to two masks.

Whether or not a cutting line is drawn from each interior angle is determined by a stability value that is a function of the length of the side adjacent to the interior angle and a stability limit function that depends on the physical characteristics of the mask. It is done based on. In this publication, for example, a cutting line shown by a dotted line is added to a polygonal pattern shown by a solid line in FIG.
An example is shown in which the holes 3 are formed in the complementary masks by allocating to the complementary division patterns shown in FIGS. 2B and 2C.

This publication describes using a silicon membrane having a thickness of, for example, about 3 μm. Therefore, as compared with the case of LEEPL in which a silicon membrane thinner than this, for example, a thickness of 500 nm is used, the influence of the shape of the divided pattern on the positional displacement and distortion of the hole is small.

On the other hand, according to the method described in Japanese Patent Laid-Open No. 2001-57331, the membrane is divided into a large number of regions, and patterns having different line widths are divided so that the line widths are substantially the same in the region, These are distributed to two complementary masks. Preferably, the patterns are distributed so that the pattern density is substantially uniform between the regions in the same mask.

According to this method, when there is a large-area pattern as shown by the solid line in FIG. 23 (a) in a certain area, the line width becomes substantially the same as shown by the dotted line.
Divide the pattern. The divided pattern is shown in FIG.
As shown in (b) and (c), the holes 3 are formed by dividing the mask into two complementary masks.

The distribution of patterns described in Japanese Patent Laid-Open No. 2001-57331 is performed by dry etching for forming holes in a mask, in which the etching rate varies between patterns having different line widths (micro loading effect) or pattern density. The variation of the etching rate (loading effect) between different areas of
It is performed for the purpose of forming holes with high precision. Therefore, this publication does not consider displacement or distortion of the hole depending on the shape or size of the hole.

In this publication, for example, a silicon membrane having a thickness of about 2 μm is used to divide a large area pattern into L / S patterns. However, according to LEEPL, for example, a silicon membrane having a thickness of 500 nm is used. Therefore, when the holes are formed in the L / S pattern, the membrane is damaged in a specific direction, or the positional displacement or distortion of the holes occurs in a specific direction. It is easy to happen.

The present invention has been made in view of the above problems. Therefore, the present invention is directed to a mask capable of transferring a large area pattern without causing positional displacement or distortion of the pattern, a method of manufacturing the same, and a semiconductor device. It aims at providing the manufacturing method of.

[0024]

In order to achieve the above object, the mask of the present invention comprises a first complementary mask including a first thin film, a second complementary mask including a second thin film, and A third complementary mask including a thin film of No. 3 and a hole through which the charged particle beam is formed, formed in each of the first to third thin films, and the hole of the first thin film has a transfer pattern. Are formed by a first complementary division pattern configured by selecting small regions that are not adjacent to each other from a plurality of polygonal small regions divided by dividing lines, and the holes of the second thin film are One complementary division pattern, which is not included in one complementary division pattern and is formed by selecting the small regions that are not adjacent to each other, is formed by the second complementary division pattern, and the holes of the third thin film are formed in the first and second holes. All the small areas that are not included in any of the complementary division patterns. Te, and is formed in the third complementary division pattern composed of the small regions that are not adjacent to each other,
The division line has a first division condition in which the small area in which all sides are composed of the division line is adjacent to an even number of the small areas, and the number of the division lines extending from the vertices of the small area is It is characterized by satisfying both the second division condition of three or less.

As a result, it is possible to prevent the displacement of the holes, the distortion, or the damage of the membrane due to the formation of a large-area hole in the membrane. Therefore, if the mask of the present invention is used for lithography, a fine pattern can be transferred with high accuracy.

In order to achieve the above-mentioned object, the method for manufacturing a mask of the present invention comprises a step of selecting a transfer pattern to be divided from a plurality of transfer patterns, and dividing the selected transfer pattern. A step of dividing into a plurality of polygonal small areas by lines, wherein the small area having all sides formed by the dividing lines is adjacent to an even number of the small areas; Dividing the transfer pattern so as to satisfy both the second dividing condition in which the number of dividing lines extending from the apex of the small region is 3 or less;
Selecting the small areas that are not adjacent to each other to create a first complementary division pattern; and selecting the small areas that are not included in the first complementary division pattern and are not adjacent to each other, and select a second complementary division pattern. And a step of forming all the small areas which are not included in any of the first and second complementary division patterns and which are not adjacent to each other as a third complementary division pattern. , A first thin film that is at least a portion of the first complementary mask,
Forming a hole through which the charged particle beam penetrates in the first complementary division pattern; and forming a hole through which the charged particle beam penetrates in the second thin film that is at least a part of the second complementary mask. The step of forming the second complementary division pattern and the step of forming a hole through which the charged particle beam penetrates in the third thin film that is at least a part of the third complementary mask in the third complementary division pattern. It is characterized by having.

As a result, even if a large-area hole is formed in the membrane, the displacement of the hole, distortion, or damage to the membrane can be prevented. According to the mask manufacturing method of the present invention, it is possible to manufacture a mask that can transfer a fine pattern with high accuracy.

Further, in order to achieve the above object, the method of manufacturing a semiconductor device of the present invention is the same as the method of manufacturing a semiconductor device of the present invention, which includes a hole through which a charged particle beam passes. A step of irradiating the photosensitive surface with a charged particle beam through a first complementary mask having a first complementary division pattern on the first thin film to transfer the first complementary division pattern to the photosensitive surface; Irradiating the photosensitive surface with a charged particle beam through a second complementary mask including a second thin film and having holes for transmitting the charged particle beam in the second thin film in a second complementary division pattern. A step of transferring the second complementary division pattern to the photosensitive surface, and a third thin film including a third thin film, the third thin film having a hole through which the charged particle beam is transmitted in the third complementary division pattern. Irradiate the photosensitive surface with a charged particle beam through a complementary mask. Transferring the third complementary division pattern onto the photosensitive surface, wherein the first complementary division pattern is adjacent to each other from a plurality of polygonal small areas in which the transfer pattern is divided by division lines. The second complementary division pattern is configured by selecting the small areas which are not included in the first complementary division pattern and which are not adjacent to each other, and the third complementary division pattern is selected. The pattern is all the small regions not included in any of the first and second complementary division patterns,
And the division line is configured by the small regions that are not adjacent to each other, and the small region in which all sides are the division lines is adjacent to an even number of the small regions, and The number of the dividing lines extending from the apex of the area is 3
It is characterized by satisfying both the second division condition which is equal to or less than this book. Thereby, a fine pattern can be transferred with high accuracy in lithography.

[0029]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a mask, a method of manufacturing the mask and a method of manufacturing a semiconductor device according to the present invention will be described below with reference to the drawings. (Embodiment 1) FIG. 1 is a flow chart showing a procedure for manufacturing three complementary masks by the mask manufacturing method of this embodiment. According to this embodiment, a large-area pattern is divided into a plurality of small regions, these small regions are divided into three groups to form three complementary division patterns, and these complementary division patterns form holes in three complementary masks. To form.

Step 1 (ST1) Production of a stencil mask is started. Step 2 (ST2) The pattern to be divided is identified and extracted from the pattern data.

In step 2, in addition to identifying a pattern having a certain area or more, a pattern in which stress is concentrated on the corner of the pattern is also identified. For example, a pattern having a side with a certain length or more is also a target of division. Or, for example, like a U-shaped pattern,
A pattern having a corner protruding toward the inside of the hole is also a target of division. The pattern identified as a target of division is not limited to a rectangle and may be any shape including a polygon.

Step 3 (ST3), Step 4 (ST
4) In step 3, the pattern extracted in step 2 is divided into small areas by dividing lines that satisfy the two dividing conditions in step 4. The pattern is divided into 3
It is performed for the purpose of distributing to a complementary mask of one sheet. [Division condition 1] After division, in a small area in which all sides are divided lines, the number of small areas adjacent to the small area is an even number. [Division condition 2] The number of division lines extending from the vertices of the small area after division is 3 or less.

Step 5 (ST5) Each of the divided small areas is divided into three groups so that adjacent small areas do not form the same group, and three complementary division patterns are created. Step 6 (ST6) With the shape of the three complementary division patterns, holes are formed in each of the three stencil masks, and these are used as complementary masks. Step 7 (ST7) The fabrication of the stencil mask is completed.

By forming the holes corresponding to the complementary division patterns in the three complementary masks by the above steps, it is possible to prevent the displacement and distortion of the holes in each complementary mask. Therefore, by using the mask of this embodiment for lithography, a fine pattern can be transferred with high accuracy.

The division condition 1 and the division condition 2 in step 4 will be described in detail below based on division examples. The division condition 1 will be described with reference to FIGS. FIG. 2 shows a large area pattern X, and FIGS. 3 to 5 are examples in which the pattern X of FIG. 2 is divided. 3 and 5 are examples in which the division condition 1 is satisfied, and FIG. 4 is an example in which the division condition 1 is not satisfied.

In FIG. 3, the pattern X of FIG. 2 is P1, Q.
It is divided into five small areas 1, R1, S1, and T1. After the division, the small area in which all sides are divided lines is P1. Focusing on this P1, it is checked whether the division example of FIG. 3 satisfies division condition 1. There are four small areas adjacent to P1, Q1, R1, S1, and T1, which are even numbers. Therefore, the division example of FIG. 3 satisfies the division condition 1.

For the small areas other than P1, at least one of the sides is a part of the side of the pattern X (see FIG. 2) before division. That is, since all the sides are not the small areas configured by the dividing lines, for the small areas other than P1,
It is not necessary to check whether division condition 1 is satisfied.

In FIG. 4, the pattern X of FIG. 2 is P2, Q.
It is divided into 6 small areas of 2, R2, S2, T2 and U2. After the division, the small area in which all sides are divided lines is P2. Focusing on this P2, it is checked whether the division example of FIG. 4 satisfies division condition 1. There are five small areas Q2, R2, S2, T2, and U2 adjacent to P2, which is an odd number. Therefore, the division example of FIG. 4 does not satisfy division condition 1.

In FIG. 5, the pattern X of FIG. 2 is P3, Q.
It is divided into seven small areas of 3, R3, S3, T3, U3 and V3. After the division, the small area in which all sides are divided lines is P3. Paying attention to this P3, it is checked whether or not the division example of FIG. 5 satisfies division condition 1.
Small areas adjacent to P3 are Q3, R3, S3, T3, U
3 and 6 of V3 are even numbers. Therefore, the division example of FIG. 5 satisfies the division condition 1.

The division condition 2 will be described with reference to FIGS. 3 to 6 are examples in which the pattern X in FIG. 2 is divided, FIGS. 3 to 5 are examples in which the division condition 2 is satisfied, and FIG. 6 is an example in which the division condition 2 is not satisfied.

In FIGS. 3 to 5, the vertices of all the small areas are the vertices of one or two small areas, and are not the vertices of three or more small areas. That is, the number of dividing lines extending from each vertex is 3 or less. For example, the vertex A in FIG.
The vertices of the small areas P1 and R1 overlap each other, and the number of dividing lines extending from the vertex A is three. Therefore, the division examples of FIGS. 3 to 5 satisfy division condition 2.

In FIG. 6, the pattern X of FIG. 2 is P4, Q.
It is divided into seven small areas of 4, R4, S4, T4, U4 and V4. Here, the vertex B of FIG. 6 is an overlap of the vertices of four small areas P4, Q4, U4, and V4,
It is the apex of three or more small areas. Further, the number of dividing lines extending from the vertex B is four, which exceeds three. Therefore, the division example of FIG. 6 does not satisfy division condition 2. When the small region is point contact, the number of dividing lines is 4 or more, and the dividing condition 2 is not satisfied. Therefore, the small area that makes point contact may or may not be included in the number of adjacent areas.

The processes in steps 3 to 5 in FIG. 1 are summarized as follows for the division examples in FIGS. 3 to 6.
In the division example of FIG. 3, the division condition 1 and the division condition 2 in step 4
Since both of the above are satisfied, the small area can be distributed in step 5.

Here, the three complementary division patterns created by allocating the small areas in step 5 are defined as complementary division patterns I to III. For example, P1 in FIG. 3 is a complementary division pattern I, Q1 and S1 are a complementary division pattern II,
R1 and T1 are assigned to complementary division patterns III, respectively. Accordingly, in each complementary mask, holes having a shape corresponding to the small area can be formed separately from each other.

The division example of FIG. 5 is similar to the division example of FIG.
Since both the division condition 1 and the division condition 2 in step 4 are satisfied, the small area can be distributed in step 5. For example, P3 in FIG.
3, S3, U3 as complementary division pattern II, R3, T
3 and V3 are assigned to the complementary division pattern III, respectively. Accordingly, in each complementary mask, holes having a shape corresponding to the small area can be formed separately from each other.

In the division example of FIG. 4, the division condition 1 of step 4 is used.
Does not meet. Assuming that P2 in FIG.
, Q2 and S2 as complementary division pattern II, and R2 and U2
When each is divided into complementary division patterns III, holes having shapes corresponding to these small regions are not adjacent to each other in the same complementary mask.

However, the remaining T2 cannot be distributed to any of the three complementary division patterns I to III without adjoining other small areas. T2 is P2, S
It is adjacent to any one of the small areas of 2 and U2. When a hole having a large diameter is formed in one of the three complementary masks in a pattern in which T2 is adjacent to another small region, the complementary mask is likely to cause displacement and distortion of the hole. Therefore,
According to the present embodiment, if at least one of the division condition 1 and the division condition 2 is not satisfied, the processing after step 5 is not performed.

In the division example of FIG. 6, the division condition 1 of step 4 is used.
And the division condition 2 are not both satisfied. Assuming that P4 in FIG.
To the complementary division pattern I, Q4 and S4 to the complementary division pattern II, and R4, T4, and V4 to the complementary division pattern III.
, The holes having the shapes corresponding to these small regions are not adjacent to each other in the same complementary mask.

However, U4 is a complementary division pattern I
U4 is adjacent to P4. Or U
4 to the complementary division pattern III, U4 becomes T
Adjacent to both 4 and V4 subregions. In these cases, 3
A large-diameter hole is formed in one of the complementary masks,
The complementary mask is likely to cause displacement and distortion of the holes.

On the other hand, when U4 is distributed to the complementary division pattern II, U4 is not adjacent to another small area via a side, but is in contact with Q4 at the apex. Therefore, at the apex where U4 and Q4 contact, the strength of the membrane becomes low, the membrane is easily damaged, and the holes are distorted. Therefore, according to the present embodiment, if both the division condition 1 and the division condition 2 are not satisfied, the processing from step 5 onward is not performed.

When the three complementary division patterns created in step 5 of FIG. 1 are overlapped, all the division lines are included in any of the complementary division patterns. The dividing line may be a wide line. For example, when three complementary division patterns are overlapped, even if an overlapping portion occurs in a part of a small area, if the overlapping portion is regarded as a thick dividing line and division condition 1 and division condition 2 are satisfied, The mask manufacturing method of this embodiment shown in FIG. 1 can be applied.

(Embodiment 2) Another example will be described in which a large area pattern is divided into a plurality of small areas and is distributed to three complementary masks as complementary division patterns. The rectangle shown by the outermost line in FIG. 7 corresponds to the large-area pattern Y before division. The pattern Y is divided into 36 sub-regions in total, and these sub-regions are divided into three groups, group C, group D and group E. The small areas of the C group are 12 C1 to C12, the small areas of the D group are 12 of D1 to D12, and the small areas of the E group are E1.
It is 12 pieces of E12.

The division example of FIG. 7 satisfies both the division condition 1 and the division condition 2 described above. In FIG. 7, the small areas in which all sides are divided lines are D5, C5, and C.
2, E6, D10, D6, C6, C3, E7, D11,
There are 15 D7, C7, C4, E8 and D12. Each of these small areas is adjacent to the six small areas.
That is, the number of adjacent small areas is an even number, and the division condition 1 is satisfied. Further, the number of dividing lines extending from the vertices of each small region is 3 or less, which satisfies the dividing condition 2.

8 to 10 show complementary division patterns created in the division example of FIG. Small areas of group C are distributed to the complementary division pattern in FIG. Similarly, the small areas of the D group are allocated to the complementary division pattern of FIG. 9, and the small areas of the E group are allocated to the complementary division pattern of FIG. In each of FIGS. 8 to 10, the small areas are separated from each other and there is no adjacent small area. Therefore, if holes are formed in the three complementary masks with these three complementary division patterns, a large-diameter hole is not formed, and displacement of the holes, distortion, or damage to the membrane is prevented.

(Third Embodiment) FIG. 11 shows another example in which a large area pattern is divided into a plurality of small areas. The rectangle shown by the outermost line in FIG. 11 corresponds to the large-area pattern Z before division. The pattern Z is divided into a total of 36 small areas, and these small areas are divided into three groups of F group, G group and H group. The F group has 12 small regions F1 to F12, the G group has 12 small regions G1 to G12, and the H group has 12 small regions H1 to H12.

The division example in FIG. 11 satisfies both the division condition 1 and the division condition 2 described above. In FIG.
The small area where all sides are divided lines is F5, H5,
H2, G6, F6, H6, H3, G7, F7, H7, H
There are 12 of 4, G8. Each of these subregions
It is adjacent to 6 small areas. That is, the number of adjacent small areas is an even number, and the division condition 1 is satisfied.
Further, the number of dividing lines extending from the vertices of each small region is 3 or less, which satisfies the dividing condition 2.

12 to 14 show complementary division patterns created in the division example of FIG. Small regions of the F group are distributed to the complementary division pattern of FIG. Similarly,
In the complementary division pattern of FIG.
The small areas of the H group are respectively allocated to the complementary division pattern of. In each of FIGS. 12 to 14, the small areas are separated from each other and there is no adjacent small area.

Therefore, if holes are formed in the three complementary masks with these three complementary division patterns, a hole having a large diameter is not formed, and displacement of the holes, distortion, or damage to the membrane is prevented. As shown in the third embodiment, the shape of the small area is not limited to the rectangle shown in the second embodiment, and may be other than the rectangle as long as the division condition 1 and the division condition 2 are satisfied.

(Embodiment 4) FIG. 15A shows an example of a donut pattern, and FIG. 15B shows an example in which the pattern of FIG. 15A is divided into a plurality of small areas. Figure 15
As shown in FIG. 15B, the donut-shaped pattern in FIG. 15A is divided into a total of 30 small areas, and these small areas are I
It is divided into three groups, group J, and group K. There are 10 small areas I1 to I10 in the group I, and J1 is a small area in the group J.
~ 10 J10, K group small area is K1 ~ K10
It is an individual.

The division example in FIG. 15B satisfies both the division condition 1 and the division condition 2 described above. Figure 15
In (b), there are six small areas I1, K5, J8, I3, K6, and J10 in which all sides are divided lines. Each of these small areas is adjacent to the six small areas. That is, the number of adjacent small areas is an even number, and the division condition 1 is satisfied. Further, the number of dividing lines extending from the vertices of each small region is 3 or less, and the dividing condition 2
Meets

16 to 18 show complementary division patterns created in the division example of FIG. 15 (b). Small areas of group I are distributed to the complementary division pattern in FIG. Similarly, in the complementary division pattern of FIG.
In the complementary division pattern of FIG. 18, the small areas of the K group are respectively assigned. In each of FIGS. 16 to 18,
The small areas are separated from each other, and there are no adjacent small areas.

Therefore, if holes are formed in the three complementary masks with these three complementary division patterns, a hole having a large diameter is not formed, and displacement of the holes, distortion, or damage to the membrane is prevented. As shown in the fourth embodiment, the division condition 1 and the division condition 2 can be applied even when the transfer pattern has a donut shape.

(Embodiment 5) This embodiment relates to a method of manufacturing a semiconductor device, and includes a step of performing electron beam transfer lithography using the stencil mask manufactured in the above Embodiments 1 to 4. In this lithography step, first, a wafer to which a resist has been applied in advance is exposed using one of the three complementary masks, and one of the complementary division patterns is transferred to the resist.

Next, multiple exposure is performed using another complementary mask to transfer another one of the complementary division patterns to the resist. Further, multiple exposure is performed using the remaining one complementary mask, and the remaining 1 of the complementary division pattern is formed on the resist.
Transfer one. As a result, a desired transfer pattern composed of three complementary division patterns is transferred.

According to the method for manufacturing a semiconductor device of the above-described embodiment of the present invention, since the complementary mask in which the displacement and distortion of the holes are reduced is used, each complementary division pattern is transferred to the resist with high accuracy. Therefore, the positioning accuracy of the complementary division patterns is high, and it is also possible to connect the fine patterns with high accuracy.

The embodiments of the mask, the method for manufacturing the mask, and the method for manufacturing the semiconductor device of the present invention are not limited to the above description. For example, the mask of the present invention and the manufacturing method thereof are
The present invention can also be applied to a mask other than the electron beam transfer lithography, for example, a mask for ion beam lithography and a manufacturing method thereof.

Alternatively, the mask of the present invention can be used in a semiconductor device manufacturing process other than lithography using a charged particle beam, such as ion implantation. Also,
The holes of the pattern determined to be division-free in step 2 of FIG. 1 may be formed in at least one of the three complementary masks, and how many complementary masks are formed or in which complementary mask. It is not limited whether to do it. Besides, various modifications can be made without departing from the scope of the present invention.

[0068]

According to the mask of the present invention, it is possible to prevent positional deviation and distortion of the transferred pattern. According to the mask manufacturing method of the present invention, it is possible to manufacture a complementary mask in which displacement and distortion of holes are reduced. According to the method for manufacturing a semiconductor device of the present invention, a fine pattern can be transferred with high accuracy.

[Brief description of drawings]

FIG. 1 is a flow chart showing a mask manufacturing method of the present invention.

FIG. 2 relates to the first embodiment of the present invention and shows an example of a large area pattern.

FIG. 3 relates to the first embodiment of the present invention and is an example of division of the pattern of FIG.

FIG. 4 relates to the first embodiment of the present invention and is an example of division of the pattern of FIG.

FIG. 5 relates to the first embodiment of the present invention and is an example of division of the pattern of FIG.

FIG. 6 relates to the first embodiment of the present invention and is an example of division of the pattern of FIG.

FIG. 7 relates to the second embodiment of the present invention and shows an example of division of a large area pattern.

FIG. 8 relates to Embodiment 2 of the present invention and shows a complementary division pattern based on FIG. 7.

FIG. 9 relates to the second embodiment of the present invention and shows a complementary division pattern based on FIG. 7.

FIG. 10 relates to the second embodiment of the present invention and shows a complementary division pattern based on FIG. 7.

FIG. 11 relates to the third embodiment of the present invention and shows an example of division of a large area pattern.

FIG. 12 relates to the third embodiment of the present invention, and FIG.
2 shows a complementary division pattern based on.

FIG. 13 relates to the third embodiment of the present invention, and FIG.
2 shows a complementary division pattern based on.

FIG. 14 relates to Embodiment 3 of the present invention, and FIG.
2 shows a complementary division pattern based on.

15 (a) shows an example of a donut-shaped pattern according to Embodiment 4 of the present invention, and FIG. 15 (b) shows FIG.
An example of pattern division of (a) is shown.

16 relates to Embodiment 4 of the present invention, and FIG.
The complementary division pattern based on (b) is shown.

FIG. 17 relates to the fourth embodiment of the present invention, and FIG.
The complementary division pattern based on (b) is shown.

FIG. 18 relates to Embodiment 4 of the present invention, and FIG.
The complementary division pattern based on (b) is shown.

FIG. 19 is a schematic diagram of exposure by LEEPL.

FIG. 20 is a top view of a stencil mask.

FIG. 21 is a top view of a stencil mask.

22A is an example of a pattern to be divided, and FIGS. 22B and 22C are examples in which the pattern of FIG. 22A is divided by a conventional method.

23A is an example of a pattern to be divided, and FIGS. 23B and 23C are examples in which the pattern of FIG. 23A is divided by a conventional method.

[Explanation of symbols]

1a, 1b ... Electron beam, 2 ... Stencil mask, 3, 3a
… Pore, 4… Membrane.

Claims (11)

[Claims] 1. A first complementary mask including a first thin film, a second complementary mask including a second thin film, a third complementary mask including a third thin film, and the first to the third. And a hole through which the charged particle beam is formed in the thin film of the first thin film, wherein the holes of the first thin film are adjacent to each other from a plurality of polygonal small areas in which the transfer pattern is divided by dividing lines. Formed by a first complementary division pattern formed by selecting small areas that are not selected, and the holes of the second thin film are not included in the first complementary division pattern and are not adjacent to each other. And the holes of the third thin film are all the small regions not included in either of the first and second complementary division patterns. And a third region composed of the small regions that are not adjacent to each other The division line is formed by a complementary division pattern, and the division line has a first division condition in which all the sides of the division line are adjacent to the even number of the division regions, A mask that satisfies both the second dividing condition in which the number of extending dividing lines is 3 or less. 2. The mask according to claim 1, wherein the area of the transfer pattern is not less than a predetermined area. 3. The mask according to claim 1, wherein a length of the transfer pattern in one direction is not less than a predetermined length. 4. A part of the outer shape of the transfer pattern projects toward the inside of the transfer pattern.
The listed mask. 5. The mask according to claim 1, wherein the transfer pattern has a donut shape in which a central portion is separated from the surroundings. 6. A step of selecting a transfer pattern to be divided from a plurality of transfer patterns, and a step of dividing the selected transfer pattern into a plurality of polygonal small areas by dividing lines. The small area in which all sides are composed of the dividing lines has an even number of small areas adjacent to the first dividing condition, and the number of dividing lines extending from the apex of the small area is 3 or less. Dividing the transfer pattern so as to satisfy both of the second division conditions; selecting the small regions that are not adjacent to each other to create a first complementary division pattern; and the first complementary division. Selecting the small areas that are not included in the pattern and not adjacent to each other to create a second complementary division pattern; and all the small areas that are not included in the first and second complementary division patterns so And forming the small regions which are not adjacent to each other as a third complementary division pattern, and the first thin film which is at least a part of the first complementary mask has a hole through which the charged particle beam passes. A step of forming the first complementary division pattern, and a step of forming a hole through which the charged particle beam penetrates in the second thin film, which is at least a part of the second complementary mask, in the second complementary division pattern. A method of manufacturing a mask, comprising the step of forming a hole through which a charged particle beam penetrates in the third thin film, which is at least a part of the third complementary mask, in the third complementary division pattern. 7. The mask manufacturing method according to claim 6, wherein the step of selecting the transfer pattern to be divided includes the step of selecting a transfer pattern having an area equal to or larger than a predetermined area. 8. The method of manufacturing a mask according to claim 6, wherein the step of selecting the transfer pattern to be divided includes the step of selecting a transfer pattern having a length in one direction that is equal to or longer than a predetermined length. 9. The method for manufacturing a mask according to claim 6, wherein the step of selecting the transfer pattern to be divided includes the step of selecting the transfer pattern whose outer shape is partially projected toward the inside of the transfer pattern. 10. The method of manufacturing a mask according to claim 6, wherein the step of selecting the transfer pattern to be divided includes the step of selecting a donut-shaped transfer pattern having a central portion separated from the periphery. 11. A charged particle beam is formed on a photosensitive surface through a first complementary mask including a first thin film and having holes for transmitting the charged particle beam in the first thin film in a first complementary division pattern. Irradiating to transfer the first complementary division pattern onto the photosensitive surface; and a hole including a second thin film, through which the charged particle beam is transmitted,
Irradiating the photosensitive surface with a charged particle beam through a second complementary mask having a second complementary division pattern on the thin film to transfer the second complementary division pattern to the photosensitive surface, And a hole through which a charged particle beam is transmitted,
Irradiating the photosensitive surface with a charged particle beam through a third complementary mask having a third complementary division pattern on the thin film to transfer the third complementary division pattern to the photosensitive surface. The first complementary division pattern is configured by selecting small areas that are not adjacent to each other from a plurality of polygonal small areas in which the transfer pattern is divided by division lines, and the second complementary division pattern is , The third complementary division pattern is included in both the first and second complementary division patterns, and is configured by selecting the small regions that are not included in the first complementary division pattern and are not adjacent to each other. Not all of the small areas, and is composed of the small areas that are not adjacent to each other, the dividing line, the small area of which all sides are formed by the dividing line, an even number of the small areas Adjacent A method of manufacturing a semiconductor device satisfying both a first division condition and a second division condition in which the number of the division lines extending from the apex of the small region is 3 or less.