JP3527839B2 - Components for semiconductor device manufacturing equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an inner wall member of a semiconductor manufacturing apparatus directly exposed to a fluorine-based or chlorine-based corrosive gas, a fluorine-based or chlorine-based plasma, and a support for supporting an object to be processed. The present invention relates to a semiconductor device manufacturing apparatus member suitable as a jig.

[0002]

2. Description of the Related Art The use of plasma such as dry process and plasma coating used in the manufacture of highly integrated circuit devices such as semiconductor devices has been rapidly progressing in recent years. As a plasma process in semiconductor manufacturing, a halogen-based corrosive gas such as a fluorine-based gas is used for vapor phase growth, etching and cleaning because of its high reactivity.

Members exposed to these corrosive gases or their plasmas are required to have high corrosion resistance. Conventionally, for members other than the object to be processed, which come into contact with these plasmas, materials such as glass and quartz having SiO ₂ as a main component and metals such as stainless steel and monel are often used.

Further, ceramics such as alumina, sapphire, and silicon carbide are used as a material for forming a susceptor for supporting and fixing a Si wafer or the like when manufacturing a semiconductor element.

[0005]

However, conventionally used glass and quartz have insufficient corrosion resistance in plasma and are highly consumed, and particularly when they come into contact with fluorine or chlorine-based plasma, the contact surface is etched and the surface texture is deteriorated. Change and the etching conditions are affected.

Further, since members made of metal such as stainless steel have insufficient corrosion resistance, corrosion causes a defective product particularly in semiconductor manufacturing.

Although ceramics such as alumina, aluminum nitride, and silicon carbide have excellent corrosion resistance to fluorine-containing gas as compared with the above-mentioned glasses and metals, when they are exposed to plasma at a high temperature, corrosion gradually progresses and the surface of the ceramics Therefore, there is a problem in that crystal grains are shattered, and the shattered crystal grains (particles) have an adverse effect on manufacturing of semiconductor elements.

In particular, with respect to finer wiring on the order of submicrons associated with higher integration of semiconductors and a cleaner environment in the manufacturing process, the generation of such particles causes disconnection and defects in the wiring pattern, resulting in device characteristics. There is a risk of causing problems such as deterioration of the product and a decrease in yield.

The present invention is for a semiconductor manufacturing apparatus which has excellent corrosion resistance against halogenated gas and its plasma, and does not adversely affect semiconductor manufacturing even if particles are generated due to the progress of corrosion. It is intended to provide a member.

[0010]

DISCLOSURE OF THE INVENTION The inventor of the present invention is capable of completely preventing the progress of corrosion even with a ceramic having excellent corrosion resistance to a fluorine-based or chlorine-based halogenated gas or its plasma. Is difficult and the generation of particles due to it is not completely suppressed,
As a result of repeated studies on corrosion-resistant members that do not adversely affect semiconductor manufacturing even when particles are generated, the maximum crystal grain size of ceramics with high corrosion resistance to these gases is determined by the wiring pattern of semiconductor elements. It is smaller than the line width and 8 from the minimum line distance.
It was found that the influence of particles can be minimized by setting the content to 0% or less, and the present invention has been completed.

That is, the present invention is a member installed in an apparatus for manufacturing a semiconductor device by treating a semiconductor wafer with a halogen-based gas or plasma thereof, and at least the halogen-based gas or plasma thereof. The surface to be exposed to is formed of corrosion-resistant ceramics having a relative density of 97% or more, a maximum crystal grain size smaller than the minimum line width of the wiring pattern in the semiconductor element , and 80% or less than the minimum line distance . In particular, the maximum crystal grain size of ceramics is 20
0 nm or less, the corrosion-resistant ceramics contains at least one selected from the group consisting of silicon carbide, silicon nitride, aluminum nitride, boron carbide, magnesia, alumina, spinel compounds, rare earth oxides and alumina-rare earth oxide compounds. It is characterized by

The semiconductor element manufacturing apparatus member of the present invention is a member installed in an apparatus for manufacturing a semiconductor element by processing a semiconductor wafer with a halogen-based gas or its plasma, and at least The surface exposed to the halogen-based gas or its plasma is formed of corrosion-resistant ceramics having a relative density of 97% or more and a maximum crystal grain diameter of 200 nm or less. Further, the member for semiconductor device manufacturing apparatus of the present invention
The manufacturing method is for ceramics with a primary particle diameter of 200 nm or less.
After molding the raw material powder into the specified shape,
The minimum grain width of the wiring pattern in a semiconductor device
Smaller than 80% or less than the minimum distance between lines, relative density
Is characterized by firing so that
Therefore, the ceramic raw material powder is sol-gel method, gas phase
It is preferable that it is made by a synthesis method or a plasma synthesis method.
Yes .

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The member for a semiconductor device manufacturing apparatus of the present invention is used for performing an etching process by a halogen-based gas or its plasma when forming a wiring pattern on a semiconductor wafer, a film forming process and the like. It is applied to the manufacturing equipment.

More specifically, a structural member in the manufacturing apparatus, for example, a part or all of which is exposed to the halogen-based gas in the manufacturing apparatus or the plasma thereof, for example,
The present invention relates to members such as an inner wall of an apparatus, a gas nozzle, a spacer ring, and an electrostatic chuck.

The halogen-based corrosive gas or plasma to which the member of the present invention is exposed is fluorine-based or chlorine-based corrosive gas.
Fluorine-based gases such as F ₆ , CF ₄ , CHF ₃ , ClF ₃ and HF, and chlorine-based gases such as Cl ₂ , BCl ₃ and HCl are mentioned. Microwaves, high frequencies, etc. are introduced into the atmosphere into which these gases are introduced. Is introduced to convert these gases into plasma.

In the corrosion-resistant member of the present invention, at least the surface exposed to the above-mentioned gas or plasma has high corrosion resistance, specifically, silicon carbide, silicon nitride, aluminum nitride, boron carbide, magnesia, alumina, spinel, etc. Of magnesia-alumina compound, rare earth oxides such as yttria and ceria, and alumina-rare earth oxide compounds such as yttrium aluminum garnet (YAG).

Further, according to the present invention, it is important that the ceramic is a dense body having a relative density of 97% or more, preferably 98% or more. This is because if the relative density is less than 97%, the ceramics will have many pores, the contact area with the corrosive gas or plasma will increase, and the consumption will increase, that is, the corrosion rate will increase. .

As the corrosive gas on the surface of the ceramic and its corrosion progress by the plasma, crystal grains are shed from the surface of the ceramic. Crystal grain shedding (generation of particles) is a phenomenon in which the grain boundary phase that binds crystal grains in ceramics has a higher corrosion rate than the crystal grains, so that crystal grains that have lost the grain boundary phase fall out. hand,
Usually, it falls off in units of one crystal grain. Therefore, the generated particle size is substantially the same as or slightly smaller than the crystal particle size of ceramics.

Therefore, according to the present invention, by making the maximum crystal grain diameter in ceramics smaller than the minimum line width of the wiring pattern in the semiconductor element, even if particles are generated and fall on the wiring pattern of the semiconductor element,
It is important that the influence of the wiring pattern on the function itself can be minimized, and that the maximum crystal grain diameter is 80% or less, especially 50% or less of the minimum line width and the minimum interline distance of the wiring pattern.

Since the line width of the wiring pattern in the present semiconductor device is about 300 nm, the maximum crystal grain size is 200 nm or less, preferably 100 nm.
When it is composed of the following fine crystal particles, it can be applied to any semiconductor device manufacturing apparatus.

Therefore, if the maximum crystal grain size in the ceramics is larger than the minimum line width of the wiring pattern in the semiconductor element, there is a high possibility that the wiring pattern of the semiconductor element may be broken or short-circuited. As a result, the manufacturing yield of semiconductor elements is reduced, and the cost is increased.

To produce the ceramics of the present invention, fine powder having a primary particle diameter of 200 nm or less produced by a sol-gel method, a gas phase synthesis method or a plasma synthesis method is used as a ceramic raw material powder as a main component. Then, the main component raw material powder, or a mixed powder to which a sintering aid or the like is appropriately added is formed into a predetermined member by a desired molding means such as a die press, a cold isostatic press, injection molding, and extrusion molding. After being shaped into a shape, it is densified by firing to a relative density of 97% or more. As a firing method, firing can be performed under known conditions depending on the main component composition used,
Examples include normal pressure firing, hot pressing, atmospheric gas pressure firing method, hot isostatic pressure firing method, and microwave firing method.

[0023]

EXAMPLES First, members made of each ceramic shown in Table 1 were prepared. The primary particle diameter of MgO ceramics is 1
The MgO raw material powder having a particle size of 0 to 200 nm is molded and then fired at 1300 ° C. in the air atmosphere.

The Al ₂ O ₃ ceramics have a diameter of 1250 to 1250 after forming Al ₂ O ₃ raw material powder having a primary particle diameter of 80 nm.
It was baked at 500 ° C.

Spinel ceramics have a primary particle size of 5
MgO powder of 0 nm and Al ₂ O ₃ powder of 100 nm were mixed at a molar ratio of 1: 1 and after molding, the mixture was mixed in an air atmosphere for 14
It was baked at 00 ° C.

Y ₂ O ₃ ceramics have a Y of 100 nm.
₂ O ₃ raw material powder is molded and then fired at 1800 ° C. in vacuum.

YAG ceramics is Al _{2 of} 80 nm
O ₃ powder and Y ₂ O ₃ powder of 100 nm were mixed at a molar ratio of 5: 3, and then molded, and in vacuum, 1800 ° C., 1900 ° C.
It was baked in.

The relative density of each ceramic member was calculated by the Archimedes method, and the maximum crystal particle size of the ceramics was determined by observing arbitrary 5 spots from a transmission electron micrograph.

Next, these members were CF ₄ (60 sccm) + Ar in an RIE plasma etching apparatus.
The film was exposed to (60 sccm) fluorine-based plasma at room temperature, and the etching rate, the presence or absence of particles, and the maximum diameter thereof were investigated. The results are shown in Table 1. The etching conditions were a pressure of 10 Pa, an RF output of 1 kW, and a plasma irradiation time of 6 hours. The etching rate was calculated based on the weight change before and after the test, and the presence or absence of particles was observed by observing the sample surface with an electron microscope to observe the presence or absence of particles adhering to the surface. The results are shown in Table 1.

For comparison, Si single crystal, SiO
_The same evaluation was performed for ₂ single crystals (quartz), and the results are shown in Table 1.

Further, in the plasma etching apparatus, each of the above-mentioned ceramics was attached to a part of the inner wall to form Si.
The line width is 2 on the wafer by the plasma etching method.
The presence or absence of disconnection of the wiring when a fine pattern of 50 nm aluminum was formed was inspected.

[0032]

[Table 1]

According to the results shown in Table 1, the samples No. 12 and 13 made of Si and SiO ₂ (quartz) had a high etching rate and were consumed greatly. In the samples No. 1 and 4 in which the maximum crystal grain diameter of ceramics exceeds 200 nm, the generated particles are larger than the wiring pattern and disconnection occurs.

Sample No. 7, which has a relative density of less than 97%, has a high etching rate and corrosion progresses.
Corrosion resistance is greatly reduced.

On the other hand, all the members according to the present invention had a low etching rate, a high corrosion resistance, and a small particle size.

[0036]

As described in detail above, according to the present invention, a member exposed to a halogen-based corrosive gas or plasma has high corrosion resistance, and even if particles are generated, the particle diameter is very high. Since it is small, it is possible to suppress the adverse effect on the wiring pattern of the semiconductor element, and as a result, the manufacturing yield of the semiconductor element is improved,
High quality semiconductor devices can be manufactured at low cost.

─────────────────────────────────────────────────── ─── Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) H01L 21/3065 C04B 35/00-35/22

Claims (6)

(57) [Claims] 1. A member installed in an apparatus for manufacturing a semiconductor device by treating a semiconductor wafer with a halogen-based gas or plasma thereof, which is exposed to at least the halogen-based gas or plasma thereof. A semiconductor characterized in that a surface has a relative density of 97% or more, a maximum crystal grain diameter is smaller than a minimum line width of a wiring pattern in the semiconductor element, and is 80% or less than a minimum line distance between the corrosion resistant ceramics. Member for device manufacturing equipment. 2. The maximum crystal grain size of the ceramic is 20.
It is 0 nm or less, The member for semiconductor device manufacturing apparatuses of Claim 1 characterized by the above-mentioned. 3. Corrosion resistant ceramics include silicon carbide, silicon nitride, aluminum nitride, boron carbide, magnesia,
Alumina, spinel compound, rare earth oxide, alumina-
The member for a semiconductor manufacturing apparatus according to claim 1, which contains at least one selected from the group of rare earth oxide compounds as a main component. 4. A member installed in an apparatus for manufacturing a semiconductor device by treating a semiconductor wafer with a halogen-based gas or plasma thereof, which is exposed to at least the halogen-based gas or plasma thereof. The surface has a relative density of 97% or more and a maximum crystal grain size of 200 nm
A member for a semiconductor device manufacturing apparatus, which is formed of the following corrosion resistant ceramics. 5. A ceramic raw material powder having a primary particle diameter of 200 nm or less is molded into a predetermined member shape, and then the maximum crystal particle diameter is 80% or less relative to the minimum width and the minimum distance between wiring patterns of a semiconductor element, and A method for manufacturing a member for a semiconductor device manufacturing apparatus, which comprises firing so as to have a density of 97% or more. 6. The method for manufacturing a member for a semiconductor device manufacturing apparatus according to claim 5, wherein the ceramic raw material powder is manufactured by a sol-gel method, a gas phase synthesis method or a plasma synthesis method.