JPH04370928A - Semiconductor manufacturing device - Google Patents

Abstract

PURPOSE:To reduce particles in a dry etching device. CONSTITUTION:As an example of the measures for preventing deposition of reaction product on the inner wall of an etching chamber 5, the product is volatilized by heating using a film heater 8, whereby the product can be prevented from being deposited. As another example, the flow of ions is directed toward a stage electrode 2 by setting the inner wall at the highest positive potential, whereby the product can be prevented from flying.

Description

[Detailed description of the invention]

The present invention relates to a semiconductor manufacturing apparatus used in a wafer dry etching process in semiconductor manufacturing.

0002

2. Description of the Related Art One type of semiconductor manufacturing apparatus that performs dry etching is a parallel plate apparatus shown in cross section in FIG. This device includes a stage electrode 2 on which a wafer X is placed in a reduced pressure atmosphere 1 of an etching gas such as a fluorine-based etching gas or a chlorine-based etching gas, and a disc-shaped counter electrode facing the stage electrode 2. 3 are provided, and a high frequency voltage is applied between the stage electrode 2 and the counter electrode 3 by a power source 4, so that the wafer X is etched.

This etching progresses through a physical reaction by the etching gas 6 ionized by the energy of the high frequency voltage and a chemical reaction by activated halogen atoms.

0004

However, in the conventional parallel plate type semiconductor manufacturing apparatus as described above, as the number of wafers to be etched increases, the wafer Reaction products 7 generated by the gas reaction gradually accumulate. A part of the deposited reaction products reappears as particles in the reduced pressure atmosphere 1, adheres to the wafer This had the disadvantage of causing a decrease in retention.

[0005]

[Means for Solving the Problems] The object of the present invention is achieved by adding means for preventing reaction products from adhering to the inner wall of the etching chamber 5.

[0006] Means for preventing the above reaction products from adhering are as follows:
Means such as heating to a high temperature or adding an electrode inside the etching chamber 5 to maintain a more positive potential than the opposing electrode may be used.

[0007]

[Operation] According to the above structure, the accumulation of reaction products is reduced, and therefore, re-dusting as particles can be suppressed.

In the case of the heating method, even if reaction products adhere, they are volatilized and gasified, so that no deposition occurs. Further, when the potential is maintained at a positive potential, the amount of ionized etching gas flying around is reduced, so that the deposition of reaction products is also reduced. Therefore, re-dusting as particles can be suppressed.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained below with reference to the drawings. FIG. 1 is a schematic cross-sectional view of a semiconductor manufacturing apparatus to which a heating method according to an embodiment of the present invention is added.

In this case, the structure is substantially the same as that of the conventional semiconductor manufacturing apparatus described above, except that a film heater 8 is provided on the inner wall of the etching chamber 5.

In this embodiment, the inner wall of the chamber is 100
By heating to about 0.degree. C., there is an advantage that even if the reaction product adheres, it evaporates and no deposition occurs.

0012

Embodiment 2 FIG. 2 is a sectional view of a second embodiment of the present invention. In this embodiment, an additional electrode 9 is used in place of the film heater 8 of the first embodiment, and several tens to more than the counter electrode 3 are used.
Since this embodiment is the same as the first embodiment except that a power supply 10 that maintains a positive potential of several hundred volts is provided, the same reference numerals are given to the same parts and the explanation thereof will be omitted.

In this embodiment, since the additional electrode 9 has the highest positive potential in the chamber, the ionized etching gas flows toward the stage electrode. Therefore, since the reaction products also follow the flow, there is an advantage that adhesion to the inner wall can be prevented.

[0014]

As explained above, in the semiconductor manufacturing apparatus of the present invention, by preventing reaction products from adhering to the inner wall of the chamber, particle generation is eliminated regardless of the number of wafers to be etched, and semiconductor chips This has the effect that the yield can be improved.

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view of a semiconductor manufacturing apparatus according to a first embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view of a second embodiment of the invention.

FIG. 3 is a schematic cross-sectional view of a conventional semiconductor manufacturing apparatus.

[Explanation of symbols]

1 Etching gas reduced pressure atmosphere 2 Stage electrode 3 Counter electrode 4 Power supply 5 Etching chamber 6 Ionized etching gas 7 Reaction product 8 Film heater 9 Additional electrode X wafer

Claims (3)

[Claims] Claim 1: In a semiconductor manufacturing equipment in which a wafer is etched by applying a high frequency voltage between two opposing electrodes in a reduced pressure atmosphere of etching gas, a reaction is generated on the inner wall of a chamber forming a reduced pressure atmosphere. A semiconductor manufacturing device characterized by being equipped with a means to prevent objects from adhering to the device. 2. The semiconductor manufacturing apparatus according to claim 1, wherein the means for making it difficult for the reaction products to adhere is a heating means. 3. The semiconductor manufacturing apparatus according to claim 1, wherein the means for making it difficult for the reaction products to adhere is an electrode.