JP2000239058A - Ceramic member for equipment for producing semiconductor - Google Patents

Ceramic member for equipment for producing semiconductor

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Publication number
JP2000239058A
JP2000239058A JP11041323A JP4132399A JP2000239058A JP 2000239058 A JP2000239058 A JP 2000239058A JP 11041323 A JP11041323 A JP 11041323A JP 4132399 A JP4132399 A JP 4132399A JP 2000239058 A JP2000239058 A JP 2000239058A
Authority
JP
Japan
Prior art keywords
semiconductor manufacturing
ceramic member
manufacturing equipment
ceramic
thermal expansion
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP11041323A
Other languages
Japanese (ja)
Inventor
Makoto Sakamaki
Chiharu Wada
千春 和田
誠 酒巻
Original Assignee
Taiheiyo Cement Corp
太平洋セメント株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Taiheiyo Cement Corp, 太平洋セメント株式会社 filed Critical Taiheiyo Cement Corp
Priority to JP11041323A priority Critical patent/JP2000239058A/en
Publication of JP2000239058A publication Critical patent/JP2000239058A/en
Granted legal-status Critical Current

Links

Abstract

(57) [Summary] [PROBLEMS] To improve the dimensional accuracy of a semiconductor product by sufficiently suppressing a dimensional change due to a temperature change of a semiconductor manufacturing equipment, and to suppress damage to a silicon wafer and generation of particles. To provide a ceramic member for semiconductor manufacturing equipment to be obtained. SOLUTION: The dense ceramic mainly composed of lithium aluminosilicate and calcium silicate, or has a coefficient of thermal expansion of -7.0 to 7.0 at room temperature to 400 ° C.
0 × 10 −6 / ° C., Vickers hardness of 3.0 to 7.0 G
A ceramic member for semiconductor manufacturing equipment is composed of dense ceramics of Pa.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a silicon wafer transfer member such as a hand, an arm, a pair of tweezers, and a finger, or a vacuum chuck used in the manufacture of a semiconductor.
The present invention relates to a ceramic member for semiconductor manufacturing equipment applied to a silicon wafer holding member such as an electrostatic chuck.

[0002]

2. Description of the Related Art Conventionally, in semiconductor manufacturing equipment, a silicon wafer carrying member such as a hand, an arm, a pair of tweezers, and a finger, or a silicon wafer holding member such as a vacuum chuck or an electrostatic chuck has a metal member such as stainless steel. Has been used.

On the other hand, in recent years, as semiconductor wafers have become larger in diameter and circuit patterns have become denser, control of deformation of members, control of metal contamination on wafers, and maintenance of accuracy for a long time have been required. Ceramic members have been widely used as the above members. Ceramics used for these members include alumina,
There are silicon nitride, silicon carbide, and the like, and a change with time in accuracy is small, and it is possible to maintain high accuracy for a long time as compared with a metal member.

[0004]

However, as the diameter of wafers and the density of circuit patterns are rapidly increasing, the use of such ceramic members causes a problem that various failures occur frequently. Is happening. The causes of defects in the semiconductor manufacturing process when such a ceramic member is used include a decrease in accuracy due to thermal expansion of the ceramic member, damage of the silicon wafer due to friction between the ceramic member and the silicon wafer, and generation of particles due thereto. Can be

That is, ceramic members used in semiconductor manufacturing equipment are required to have low thermal expansion in terms of maintaining dimensional accuracy, and low hardness in terms of suppressing damage to silicon wafers. However, conventional ceramics cannot satisfy all of these requirements.

When alumina or zirconia is used as a ceramic member of a semiconductor device, for example, the coefficient of thermal expansion exceeds 7 × 10 −6 / ° C. As a result, the accuracy of the resulting semiconductor product is reduced.

Silicon carbide and silicon nitride have thermal expansion coefficients of 3.5 × 10 −6 / ° C. and 4.2 × 10
Since -6 / ° C is a small value compared to alumina,
Although the dimensional change with respect to the temperature change of the semiconductor manufacturing equipment can be improved to some extent, since these materials are high hardness materials having Vickers hardness of 15 GPa and 25 GPa, the wafer is damaged at the time of contact with the silicon wafer, and many There is a problem that particles are generated.

On the other hand, when attention is paid to low thermal expansion ceramics from the viewpoint of suppressing dimensional change due to temperature change, cordierite ceramics, aluminum titanate ceramics, quartz glass, and the like are mentioned.

However, cordierite ceramics and aluminum titanate ceramics are porous materials having a large number of pores both inside and outside the sintered body, and thus have insufficient dimensional accuracy after processing. Since it is a low-strength material, there is a problem that the dimensional accuracy is reduced due to mechanical stress before the accuracy of the dimensional change due to a thermal change, and therefore cannot be used as a ceramic member for semiconductor manufacturing equipment.

Although quartz glass has no problem in that it has low thermal expansion, high density, and low porosity, there remains a problem in the process of manufacturing members for semiconductor manufacturing equipment. In other words, quartz glass basically has a glass structure, so there is no grain boundary present in ordinary ceramics in the material, and the progress of cracks during machining is much more sensitive than other ceramics Therefore, there is a great difficulty in processing as a ceramic member for semiconductor manufacturing equipment requiring fine processing and dimensional accuracy.

The present invention has been made in view of the above circumstances, and it is possible to sufficiently suppress a dimensional change due to a temperature change of a semiconductor manufacturing device, to improve a dimensional accuracy of a semiconductor product, and to produce a silicon wafer. It is an object of the present invention to provide a ceramic member for semiconductor manufacturing equipment capable of suppressing the damage of particles and the generation of particles.

[0012]

Means for Solving the Problems The present inventors have made intensive studies to solve the above problems, and as a result, ceramics comprising lithium aluminosilicate and calcium silicate have been obtained.
It has a small coefficient of thermal expansion, can be a dense sintered body, and can have a hardness almost equal to that of a silicon wafer, so it is suitable as a ceramic member for semiconductor manufacturing equipment, It has been found that the material is capable of maintaining high dimensional accuracy with respect to temperature changes in manufacturing equipment and suppressing damage to silicon wafers and generation of particles.

Further, as a member for semiconductor manufacturing equipment, the coefficient of thermal expansion from room temperature to 400 ° C. is -7.0 to 7.0 × 1.
When a dense ceramic member having a temperature of 0 −6 / ° C. and a Vickers hardness of 3.0 to 7.0 GPa is used, high dimensional accuracy with respect to a temperature change can be maintained, and damage to a silicon wafer and generation of particles are generated. Was found to be possible.

The present invention has been made based on such findings, and a first invention is a semiconductor manufacturing method comprising a dense ceramic mainly composed of lithium aluminosilicate and calcium silicate. Provide a ceramic member for equipment.

According to a second aspect of the present invention, there is provided the ceramic for semiconductor manufacturing equipment according to the first aspect, wherein the lithium aluminosilicate is contained in an amount of 5 to 99% by weight based on the total amount of the lithium aluminosilicate and the calcium silicate. Provide a member.

The third invention is the first or the second invention, wherein the thermal expansion coefficient at room temperature to 400 ° C. is -7.0 to 7.0.
7.0 × 10 −6 / ° C., Vickers hardness is 3.0 to 7.0.
Provided is a ceramic member for semiconductor manufacturing equipment, which is characterized by having a pressure of 0 GPa.

[0017] The fourth invention is the thermal expansion coefficient of -7.0~7.0 × 10 at room temperature to 400 ° C. - 6 / ° C., the Vickers hardness of the dense ceramic is 3.0~7.0GPa Provided is a ceramic member for semiconductor manufacturing equipment characterized by the following.

According to a fifth aspect of the present invention, there is provided a ceramic member for semiconductor manufacturing equipment according to any one of the first to fourth aspects, wherein the relative density of the sintered body is 90% or more.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described specifically. As described above, in order to achieve the above object, a dense sintered body, a low thermal expansion, and a ceramic member having a low hardness are required. Therefore, in the present invention, such characteristics are required. As a ceramic member for semiconductor manufacturing equipment to be filled, a dense ceramic mainly composed of lithium aluminosilicate and calcium silicate is used.

Since the above ceramics contains lithium aluminosilicate known as a low thermal expansion material,
The coefficient of thermal expansion of the sintered body is equivalent to or lower than that of conventional ceramics, and when used as a ceramic member for semiconductor manufacturing equipment, there is little dimensional change due to temperature changes. It is an effective material for reduction.

In addition, most ceramic members for semiconductor manufacturing equipment are members that come into direct contact with a silicon wafer, and therefore are used in high hardness materials such as alumina and silicon carbide (Vickers hardness of 15 GPa and 2 GPa).
When using 5 GPa), the silicon wafer is inevitably damaged, generating many particles,
Although it has been a major problem in semiconductor manufacturing, the ceramics based on lithium aluminosilicate and calcium silicate in the present invention are similar to the hardness of a silicon wafer, so even if they come into contact with the silicon wafer, With little damage to
Further, the generation of particles due to this can be significantly reduced.

As the lithium aluminosilicate constituting the above ceramics, LAS 2 (eucryptite), LAS 4 (spodumene) are represented by L for LiO 2 , A for Al 2 O 3 and S for SiO 2. , LAS 6 (lithium orthoclase), LAS 8 (petalite) and the like. Also, as calcium silicate,
CaO is represented by C, SiO 2 is represented by S, and C 3 S, C
2 S, C 3 S 2 , and CS (wollastonite). Further, the ceramic of the present invention is preferably made of lithium aluminosilicate and calcium silicate, but other components such as Na 2 O, K 2 O, Fe 2 up to about 5% of the total amount. O 3 , MnO,
It may contain P 2 O 5 , TiO 2 and the like.

The amount of lithium aluminosilicate in the above-mentioned ceramics mainly composed of lithium aluminosilicate and calcium silicate is 5 to 99% by weight based on the total amount of lithium aluminosilicate and calcium silicate. Is preferred. If the lithium aluminosilicate content is less than 5% by weight, the coefficient of thermal expansion becomes large, and the dimensional accuracy of the ceramic member accompanying a temperature change in the semiconductor manufacturing apparatus is undesirably reduced. On the other hand, when the lithium aluminosilicate content exceeds 99% by weight, although the coefficient of thermal expansion is small, it is difficult to densify the sintered body, so that it is difficult to apply as a ceramic member for a semiconductor manufacturing apparatus. A more preferred amount of lithium aluminosilicate is 10 to 95% by weight.

The coefficient of thermal expansion of the ceramic member of the present invention is from -7.0 to 7.0 × at room temperature (20 ° C.) to 400 ° C.
It is preferably 10 −6 / ° C. Within this range, a dimensional change with respect to a temperature change of the semiconductor manufacturing apparatus can be suppressed small, and as a result, dimensional accuracy can be sufficiently improved. Thermal expansion coefficient is 7.0 × 10
If it is larger than −6 / ° C. or smaller than −7.0 × 10 −6 / ° C., a dimensional change with respect to a temperature change of the semiconductor manufacturing apparatus becomes large, which is not effective in reducing defects in semiconductor manufacturing. A preferable coefficient of thermal expansion for reducing defective semiconductor production is -2.0 to 2.0 × 10 −6 / ° C. Since the above-mentioned ceramics mainly composed of lithium aluminosilicate and calcium silicate contain lithium aluminosilicate, which is a low thermal expansion material, the coefficient of thermal expansion is from room temperature (20 ° C) to 400 ° C. -7.0 to 7.0
× 10 −6 / ° C. By adjusting the amount of lithium aluminosilicate, the coefficient of thermal expansion can be made equal to or smaller than silicon nitride and silicon carbide ceramics having a relatively small coefficient of thermal expansion among conventional materials.

The hardness of the ceramic member of the present invention is preferably 3.0 to 7.0 GPa in Vickers hardness. As described above, the required characteristics of the ceramic member for a semiconductor manufacturing apparatus include low hardness, that is, the hardness of the ceramic member is equal to the hardness of the silicon wafer (Vickers hardness 5.
0 GPa), this range is defined as a preferable range. Vickers hardness is 7.0G
If it exceeds Pa, the silicon wafer is easily damaged, which is not preferable. When the Vickers hardness is less than 3.0 GPa, the silicon wafer is not damaged, but the ceramic member itself is easily worn, the dimensional accuracy is reduced, and particles are likely to be generated in the semiconductor manufacturing equipment. It is not preferable as a ceramic member for manufacturing equipment. A more preferable Vickers hardness for reducing the defect in semiconductor manufacturing is 4.0.
It is GPa or more and 6.0 GPa or less. The ceramics mainly composed of lithium aluminosilicate and calcium silicate are not inherently hard, and can have a Vickers hardness in the range of approximately 3.0 to 7.0 GPa.

On the other hand, if the coefficient of thermal expansion from room temperature to 400 ° C. is −7.0 to 7.0 × 10 −6 / ° C. and the Vickers hardness is 3.0 to 7.0 GPa, semiconductor manufacturing equipment It is possible to maintain high dimensional accuracy with respect to temperature changes at the same time, and to suppress damage to silicon wafers and generation of particles. Therefore, if a dense ceramic having such characteristics is used, the above-mentioned lithium aluminosilicate and silicate Not only ceramics mainly composed of calcium but also other ceramics can be applied as the ceramic member for semiconductor devices of the present invention.

Since the ceramic member of the present invention is used for semiconductor equipment, it must be dense. If it is porous, contaminants enter the pores and become difficult to remove in the washing process of the product, and as a result, contamination (contamination) occurs in semiconductor manufacturing equipment.
Will be brought. In order to more effectively prevent contamination from being introduced into semiconductor manufacturing equipment, the relative density is preferably 90% or more. More preferably, the relative density is 95% or more.

The ceramic mainly composed of lithium aluminosilicate and calcium silicate is typically a sintered body obtained by liquid phase sintering and is an easily sintered material. A dense sintered body having few pores can be obtained relatively easily. That is, the relative density can be easily increased to 90% or more, and more preferably to 95% or more even in the normal pressure sintering as compared with other hardly sintering materials such as alumina and silicon carbide.

[0029]

Embodiments of the present invention will be described below. (Example 1) 9.5 kg of α-spodumene powder, which is a lithium aluminosilicate, and 0.5 kg of β-wollastonite, which is a kind of calcium silicate, were mixed and pulverized by a wet ball mill, and sprayed using a spray drier. And granulated. The obtained granules were press-formed and fired using a normal-pressure firing furnace. The obtained sintered body (L-95) is ground and polished, and is subjected to density measurement, room temperature (20 ° C.) to 100
The average coefficient of thermal expansion at 0 ° C. and Vickers hardness were measured.

Next, a pin-on-disk wear test was performed using the sintered body processed into a pin shape of φ2 mm × 20 mm. That is, the pins were pressed against the silicon wafer with a pressing load of 5 kgf, and the pins and the silicon wafer were slid by rotating the silicon wafer. When the sliding distance reached 1 km, the sliding was stopped, and the wear amount of the silicon wafer was measured by measuring the mass of the wafer before and after the sliding.

The evaluation criteria are as follows: 焼 結: dense, relative density of 95% or more, ◎: dense, but relative density less than 95%, porous: ×, and the coefficient of thermal expansion was −2.0 to 2.0 × 1
If 0 -6 / ℃ ◎, -7.0~- 2.0 × 10 -6
/ ° C and 2.0 to 7.0 × 10 −6 / ° C,
Less than -7.0 × 10 −6 / ° C. or 7.0 ×
When the Vickers hardness is 4.0 GPa or more and 6.0 GPa or less, it is evaluated as x when the hardness exceeds 10 −6 / ° C .;
0 GPa or more and less than 4.0 GPa or more than 6.0 GPa and less than 7.0 GPa ○, less than 3.0 GPa or more than 7.0 GPa ×, the wear amount of the silicon wafer is 0.1 mg or less If yes,
The case where 0.1 mg was exceeded was evaluated as x, and the overall evaluation was evaluated as ○ when all three types of evaluations were ◎ or ○, and x when there was at least one x. Table 1 shows the results.

As shown in Table 1, the ceramic sintered body of this embodiment has a smaller coefficient of thermal expansion than conventional materials, and has a hardness similar to that of silicon. It was confirmed that the ceramic member was suitable as a ceramic member.

Example 2 5.0 of α-spodumene powder
A sintered body was prepared in the same manner as in Example 1 except that the powder of β-wollastonite was changed to 5.0 kg (L-5).
0). This ceramic sintered body was tested in the same manner as in Example 1. Table 1 shows the results. As shown in Table 1, the ceramic sintered body of this example has a smaller coefficient of thermal expansion than conventional materials, and has a hardness similar to that of silicon, so that the amount of damage to a silicon wafer is extremely small. It was confirmed that it was suitable as

Example 3 α-spodumene powder was mixed with 2.5
kg, and a sintered body was prepared in the same manner as in Example 1 except that the powder of β-wollastonite was 7.5 kg (L-2).
5). This ceramic sintered body was tested in the same manner as in Example 1. Table 1 shows the results. As shown in Table 1, the coefficient of thermal expansion is similar to that of silicon nitride / silicon carbide. However, since the hardness is similar to silicon, the amount of damage to the silicon wafer is extremely small, so that it is suitable as a ceramic member for semiconductor manufacturing equipment. Was confirmed.

Example 4 α-spodumene powder was added in an amount of 0.3
A sintered body was produced in the same manner as in Example 1 except that the powder of β-wollastonite was 9.7 kg.
3). This ceramic sintered body was tested in the same manner as in Example 1. Table 1 shows the results. Since the amount of lithium aluminum silicate was small, the coefficient of thermal expansion tended to be slightly large.However, since the hardness was similar to silicon, the amount of damage to the silicon wafer was extremely small, so it was used as a ceramic member for semiconductor manufacturing equipment. It was confirmed that it was applicable.

Example 5 β-eucryptite powder was used as the lithium aluminosilicate, and the powder was used in 8.
A sintered body was produced in the same manner as in Example 1 except that 0 kg and the powder of β-wollastonite were 2.0 kg (L-
80). This ceramic sintered body was tested in the same manner as in Example 1. Table 1 shows the results. As shown in Table 1, the ceramic sintered body of this example has a smaller coefficient of thermal expansion than conventional materials, and has a hardness similar to that of silicon.
It has been confirmed that it is suitable as a ceramic member for semiconductor manufacturing equipment.

Comparative Example 1 α-spodumene powder was
A sintered body was prepared in the same manner as in Example 1 except that the weight was 0.0 kg and the powder of β-wollastonite was not added (L-100). This ceramic sintered body was tested in the same manner as in Example 1. Table 1 shows the results. Because everything is lithium aluminum silicate,
Although the coefficient of thermal expansion may be small, the sintered body was porous without being densified, and it was confirmed that the sintered body was unsuitable as a ceramic member of semiconductor manufacturing equipment.

Comparative Example 2 The same measurement as in Example 1 was performed using alumina as a comparative material. Table 1 shows the results.
Shown in As shown in Table 1, alumina has a large coefficient of thermal expansion and, when used as a ceramic member for semiconductor manufacturing equipment, has insufficient dimensional accuracy with respect to temperature changes.
Moreover, the silicon wafer is easily damaged, and cannot be said to be a suitable material.

Comparative Example 3 The same measurement as in Example 1 was performed using silicon nitride as a comparative material. Table 1 shows the results. As shown in Table 1, silicon nitride is too high in hardness to easily damage a silicon wafer and cannot be said to be a suitable material.

Comparative Example 4 The same measurement as in Example 1 was performed using silicon carbide as a comparative material. Table 1 shows the results. As shown in Table 1, silicon carbide is too high in hardness to easily damage a silicon wafer, and cannot be said to be a suitable material.

[0041]

[Table 1]

[0042]

As described above, according to the present invention,
A ceramic member for a semiconductor manufacturing device capable of sufficiently suppressing a dimensional change due to a temperature change of a semiconductor manufacturing device and improving a dimensional accuracy of a semiconductor product, and suppressing damage to a silicon wafer and generation of particles. be able to.

Claims (5)

[Claims]
1. A ceramic member for semiconductor manufacturing equipment, comprising a dense ceramic containing lithium aluminosilicate and calcium silicate as main components.
2. The amount of lithium aluminosilicate is 5 to the total amount of lithium aluminosilicate and calcium silicate.
The ceramic member for semiconductor manufacturing equipment according to claim 1, wherein the ceramic member is contained in an amount of about 99% by weight.
3. The thermal expansion coefficient between room temperature and 400 ° C. is-
7.0-7.0 × 10 −6 / ° C., Vickers hardness is 3.
The ceramic member of a semiconductor manufacturing device according to claim 1, wherein the ceramic member has a pressure of 0 to 7.0 GPa.
4. The thermal expansion coefficient between room temperature and 400 ° C. is-
7.0-7.0 × 10 −6 / ° C., Vickers hardness is 3.
A ceramic member for semiconductor manufacturing equipment, comprising a dense ceramic having a density of 0 to 7.0 GPa.
5. The ceramic member for semiconductor manufacturing equipment according to claim 1, wherein the relative density of the sintered body is 90% or more.
JP11041323A 1999-02-19 1999-02-19 Ceramic member for equipment for producing semiconductor Granted JP2000239058A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP11041323A JP2000239058A (en) 1999-02-19 1999-02-19 Ceramic member for equipment for producing semiconductor

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP11041323A JP2000239058A (en) 1999-02-19 1999-02-19 Ceramic member for equipment for producing semiconductor

Publications (1)

Publication Number Publication Date
JP2000239058A true JP2000239058A (en) 2000-09-05

Family

ID=12605326

Family Applications (1)

Application Number Title Priority Date Filing Date
JP11041323A Granted JP2000239058A (en) 1999-02-19 1999-02-19 Ceramic member for equipment for producing semiconductor

Country Status (1)

Country Link
JP (1) JP2000239058A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008255004A (en) * 2007-03-30 2008-10-23 Samsung Electro Mech Co Ltd Eucryptite ceramic filler and insulating composite material

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008255004A (en) * 2007-03-30 2008-10-23 Samsung Electro Mech Co Ltd Eucryptite ceramic filler and insulating composite material

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