KR20000066721A - Lower electrode part of cvd apparatus - Google Patents

Abstract

PURPOSE: A lower electrode part of a chemical vapor deposition apparatus is provided to prevent eddy particle owing a pressure difference from being generated. CONSTITUTION: A lower electrode part of a chemical vapor deposition apparatus comprises a susceptor(210), a heater(212) and a base(214). The heater(212) applies heat to a semiconductor wafer(215), and the base(214) supports the susceptor(210). The lower electrode part includes a medium(213), which is placed between the susceptor(210) and the base(214) and consists of quartz.

Description

LOWER ELECTRODE PART OF CVD APPARATUS}

The present invention relates to a semiconductor manufacturing apparatus, and more particularly, to a lower electrode portion of a chemical vapor deposition apparatus for forming a thin film on a semiconductor wafer.

A chemical vapor deposition process is one of semiconductor manufacturing processes in which a compound gas is supplied onto the semiconductor wafer in a semiconductor manufacturing process to generate a gaseous or chemical reaction on the surface of the semiconductor wafer to form a desired film quality.

1 is a diagram illustrating a lower electrode portion of a conventional chemical vapor deposition apparatus. Specifically, Figure 1 is an example of a GENUS 7000 model facility for depositing metal thin films.

Referring to FIG. 1, a semiconductor wafer 102 is placed on top of a susceptor 104. The heater 106 is positioned under the susceptor 104. Underneath the heater 106 is a base 108 for supporting the susceptor 104. A predetermined space 107 is formed between the base 108 and the heater 106, and argon (Ar) gas is injected into the opening 110 formed on one surface of the base 108. The heater 106 generates high temperature heat (about 400 degrees) so that the heat is transferred to the semiconductor wafer 102 through the susceptor 104. In this case, since the chemical vapor deposition apparatus proceeds at low pressure, the mass transfer rate of gas is very large, and the process is affected by temperature. Thus, the flow of argon gas flowing between the susceptor 104 and the heater 106 loaded with the semiconductor wafer 102 plays a very important role in heat transfer.

However, since the argon gas is supplied in a manner of being injected from the opening 110, the density and distribution of argon gas in the predetermined space 107 are changed, so that the argon gas is supplied from the heater 106 to the semiconductor wafer 102. Temperature transfer becomes unstable so that uniform heat transfer to the semiconductor wafer 102 is not performed, and heat is transferred to the inner wall 105 of the process chamber at a relatively low temperature, thereby causing a temperature loss. In addition, in FIG. 1, the pressure of the gases located in the upper region denoted by A, that is, the region above the semiconductor wafer 102, is denoted by the region B, that is, the predetermined space 107 of the base 108 and the susceptor 104. The pressure difference is higher than that of argon gas. Due to the generated pressure difference, the compound gases in the upper region flow into the predetermined space 107 to cause a gas reaction. By-products produced in this reaction are easily dispersed. Therefore, a problem arises in that dispersed byproducts act as particles that make a thin film deposited.

The present invention has been made to solve such a conventional problem, and an object thereof is to provide a lower electrode portion of a new type of chemical vapor deposition apparatus capable of simultaneously preventing particles and improving heat transfer to a semiconductor wafer.

1 is a diagram for showing a lower electrode portion of a conventional chemical vapor deposition apparatus;

2 is a diagram for schematically showing a chemical vapor deposition apparatus according to an embodiment of the present invention;

3 is a diagram showing a lower electrode portion of a chemical vapor deposition apparatus according to an embodiment of the present invention.

* Explanation of symbols for the main parts of the drawings

200: chemical vapor deposition apparatus 202: injection hole

204: high frequency power supply 206: gas diffusion plate

208: gas injection plate 210: susceptor

212 heater 214 base

213: Medium 215: Semiconductor Wafer

216: inflow line

According to a feature of the present invention for achieving the above object, the lower electrode portion of the chemical vapor deposition apparatus for depositing a thin film on a semiconductor wafer has a susceptor, a base and a medium. The susceptor supports the semiconductor wafer. The base supports the susceptor at the bottom of the susceptor. The medium is located between the susceptor and the base to allow gas supplied from the outside into the center of the lower portion of the susceptor.

By applying the present invention as described above, it is possible to prevent the generation of vortex particles due to the pressure difference during the deposition process, so that the yield of the semiconductor wafer is improved. In addition, since heat transfer to the semiconductor wafer is improved, a thin film of good quality is formed.

Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS. 2 to 3. Like reference numerals designate like elements.

2 is a diagram for schematically showing a chemical vapor deposition apparatus according to an embodiment of the present invention, and FIG. 3 is a diagram for showing a lower electrode portion of the chemical vapor deposition apparatus according to an embodiment of the present invention.

2 and 3, a chemical vapor deposition method in which a highly reactive gaseous compound is injected into a reactor and activated using light, heat, plasma, microwave, or electric field to form a high quality film on a semiconductor substrate. Although there are disadvantages in that harmful gases are frequently used, they are widely used due to the advantages of being suitable for the synthesis of high purity materials and having various applications. The chemical vapor deposition apparatus may be classified into various items according to a method of exciting a gas, a raw material, a temperature of a gas phase or a substrate, a pressure of a reactive component, and the like. Commonly used systems are atmospheric pressure CVD, low pressure CVD, plasma enhanced CVD and metal organic CVD. ).

In the chemical vapor deposition apparatus according to the embodiment of the present invention, a compound gas such as WF ₆ or SiH _{4 is} brought into a low pressure state of 0.1 to several Torr using a vacuum pump to react the gas under a constant temperature so that tungsten or It is a low pressure thin film chemical vapor deposition system for making tungsten silicide film. The chemical vapor deposition apparatus 200 includes a gas inlet 202 for process gas, a high frequency power supply unit 204 to which high frequency power for dry cleaning is supplied, and a gas diffusion plate 206 for supplying gas to the semiconductor wafer 215. ) And a gas jet plate 208, wherein the above-described devices are located in the upper electrode portion. The susceptor 210, the heater 212, and the base 214 on which the semiconductor wafer 215 is loaded are positioned in the lower electrode part corresponding to the upper electrode part. The heater 212 applies about 400 heat to the semiconductor wafer 215. The base 214 supports the susceptor 210. A medium (using a quartz material in the embodiment of the present invention) 213 is inserted into an inner space between the heater 212 and the base 214. Then, the volume of the internal space is reduced, and the pressure increases by the reduced volume. When the pressure increases in the inner space, the compound gases in the upper region do not flow into the inner space as in the prior art, so that the vortex particles generated by the pressure difference as in the prior art no longer occur. In addition, the medium 213 is provided with an inlet line 216 through which gas can be transferred. Thus, argon (Ar) gas, which is conventionally injected from one surface of the base 214, flows along the inflow line 216 to flow close to the center of the surface immediately below the heater 212. Since argon gas flowing through the inlet 216 flows close to the bottom of the heater 212 without being dispersed as in the prior art, the argon gas flows to the susceptor 210 in a state where the contact density with the heater 212 is increased. Because of the flow, it is possible to improve the effect of temperature transfer to the susceptor 210. Since heat transfer to the susceptor 210 is improved, heat may be effectively transferred to the semiconductor wafer 215 loaded on the susceptor 210.

By applying the present invention as described above, it is possible to prevent the generation of vortex particles due to the pressure difference during the deposition process, so that the yield of the semiconductor wafer is improved. In addition, since heat transfer to the semiconductor wafer is improved, a thin film of good quality is formed.

Claims (3)

In the lower electrode portion of the chemical vapor deposition apparatus, A susceptor on which the semiconductor wafer is placed; A base for supporting the susceptor at the bottom of the susceptor; And a medium positioned between the susceptor and the base to allow gas supplied from the outside into the center of the lower portion of the susceptor. The method of claim 1, The medium is a lower electrode of the chemical vapor deposition apparatus, characterized in that the quartz material. The method of claim 1, The lower electrode portion of the chemical vapor deposition apparatus, characterized in that the heater is located between the susceptor and the medium.