JPH07335629A - Semiconductor manufacturing device - Google Patents

Abstract

PURPOSE:To remove deposits inside a processing chamber without exposing the chamber to the air by a method wherein an insulating member is provided between the chamber and a grounding section so as to remove deposits and to apply a voltage of certain volts to the processing chamber. CONSTITUTION:An insulating joint 15 is provided between a gas feed pipe 14 and a bell jar 12 so as to insulate them from each other The insulating joint 15 is formed of, for instance, polytetrafluoroethylene. An insulating board 21 is provided between the bell jar 12 and a base chamber 13. The insulating board 21 is formed out of ceramic such as alumina. A voltage of 10V or so is applied to the bell jar 12 so as to restrain deposits from being formed on the inner surface of the bell Jar 12. By this setup, in a semiconductor manufacturing device, deposits attached to the inner face of a bell jar can be removed with a comparatively cheap means without exposing the device to the air.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor manufacturing apparatus, and more particularly to an apparatus for removing a reaction product generated by processing in the apparatus without exposing the apparatus to the atmosphere.

[0002]

2. Description of the Related Art For example, in a dry etching device,
As a large number of wafers are processed, the amount of dust generated in the apparatus increases, the process becomes unstable, and the yield decreases. It is considered that the cause is that reaction products are accumulated on the inner wall of the processing chamber and the surface of parts, dust is generated from the reaction products, and the process becomes unstable for some reason.
Therefore, the process chamber is opened to the atmosphere and the accumulated reaction product (hereinafter referred to as a deposit) is cleaned to recover the process yield. Further, as disclosed in Japanese Patent Laid-Open No. 5-166731, a method is disclosed in which the temperature of the wall surface is kept high to suppress the adsorption of gas and finally prevent deposits from adhering. .

On the other hand, Journal of Applied Physics, Volume 68 (10
No.), P.5329 to P.5336, plasma etching in trifluoroethylene gas causes an etching action when a voltage higher than a certain threshold potential is applied to a substrate of aluminum oxide. However, below the threshold potential, it was clarified that a deposition effect occurs. Although the value of the threshold potential changes depending on the temperature of the substrate, it becomes about +10 V at about 150 ° C., for example.

[0004]

However, once the apparatus is exposed to the atmosphere, it is necessary to perform vacuum evacuation again and set conditions for process stabilization before restarting the wafer processing. It has been a problem in the prior art to enable removal of deposits without exposing the device to the atmosphere.

[0005]

In order to remove deposits, an insulating member is provided between the chamber and the ground portion so that a voltage can be applied to the chamber of the processing chamber.

[0006]

Since the chamber is insulated from the grounded portion, a voltage of about +10 V can be applied to the chamber. When the etching process is performed in this state, the inner surface of the chamber is etched, and without opening to the atmosphere,
It is possible to remove deposits.

[0007]

Embodiments of the present invention will be described using a microwave etcher device as an example.

FIG. 1 shows an embodiment of the structure of the processing chamber.

The processing chamber mainly comprises a quartz window 11 and a bell jar 1.
2 and the base chamber 13, and the inside is kept in a vacuum of, for example, several mTorr or less. A microwave is introduced through the quartz window 11, and a process gas such as trifluoromethane is introduced into the processing chamber through the gas supply pipe 14. Also, the bell jar 12 may be heated to about 150 ° C. during the process. The materials of the bell jar 12 and the base chamber 13 are
For example, since it is a metal such as aluminum, it has high conductivity. The material of the gas supply pipe 14 is, for example, stainless steel, which is also conductive.

In the present invention, a voltage of about 10 V is applied to the bell jar 12 in order to suppress deposition of deposits on the inner surface of the bell jar 12. To do this, the bell jar 12 must be isolated from the ground,
Means as described below are provided.

First, in order to insulate the gas supply pipe 14 and the bell jar 12, an insulating joint 15 is provided between them.
When the material of the insulating joint 15 is, for example, polytetrafluoroethylene, it is convenient because it is chemically stable against various process gases and has a high insulation resistance. Between the bell jar 12 and the gas supply pipe 14 and the insulating joint 15,
It is connected by screws. In this embodiment, the bell jar 12 and the gas supply pipe 14 are insulated from each other, but the location of insulation is not limited. For example, the bell jar 12 and the gas supply pipe 14 are not insulated, but instead the gas supply pipe 14 and another gas supply pipe 14 connected thereto.
Insulation may be provided between the above-mentioned parts by the method shown in this embodiment.

Next, the bell jar 12 and the base chamber 1
FIG. 2 shows an example of the insulating method between the insulating layer 3 and the insulating layer 3. An insulating plate 21 is provided between the bell jar 12 and the base chamber 13. If the insulating plate 21 is made of a ceramic material such as alumina, it is convenient because it has good corrosion resistance to plasma in the processing chamber and high insulation resistance. An O-ring 22 for maintaining a vacuum is sandwiched between the insulating plate 21 and the bell jar 12 and the base chamber 13. In this embodiment, the bell jar 12 and the base chamber 13 are insulated from each other, but the location of insulation is not limited. For example, the bell jar 12 and the base chamber 13 are not insulated, but instead the base chamber 13 and a grounded component such as an exhaust pump attached thereto are insulated by the method shown in the present embodiment. You may

A cover made of alumina or the like may be covered on the outside of the bell jar 12 in order to maintain the insulation between the bell jar 12 and the parts around it. Also, bell jar 12
A coating film of polytetrafluoroethylene or aluminum fluoride may be provided on the surface of the.

Without applying a voltage to the bell jar 12 itself,
An embodiment in which a voltage is applied to a film or the like provided on the inner surface of the bell jar 12 is shown in FIG.

The surface of the bell jar 12 is covered with an insulating coating 31 such as aluminum fluoride having a high insulation resistance and a high bonding property with aluminum. A conductive coating 32 such as aluminum is provided on the insulating coating 31 on the inner surface of the bell jar 12, and a voltage is applied thereto. The provision of these coatings is not limited to the bell jar 12, but may be provided on the surface of various parts such as the wafer support in the processing chamber. Further, an inner cylinder insulated from the grounded portion may be provided in the processing chamber, and a voltage may be applied to the inner cylinder.

By the means described above, it becomes possible to apply a voltage of about 10 V to the processing chamber, the inner surface of the processing chamber or the components in the processing chamber, and to remove the deposits on those surfaces, It becomes possible to suppress the deposition of deposits. The voltage to be applied is not limited to a DC voltage, but an AC voltage with a bias voltage applied,
A voltage synchronized with the microwave introduced into the processing chamber may be used. Further, the voltage application may be performed during the process in the processing chamber, or before or after the process. Further, instead of applying the voltage, the potential of the plasma itself is set lower than that of the chamber, and it is possible to obtain the same effect as that of applying the voltage. At this time, the portion to which the voltage is applied in the above embodiment may be simply grounded.

The contents described above are not limited to the microwave etcher, but can be applied to all semiconductor manufacturing devices such as CVD devices in which deposits on the inner surface of the processing chamber pose a problem.

Further, the present invention can be applied not only to the semiconductor manufacturing apparatus but also to any apparatus or machine which needs to know the state of the inner surface or the surface of the apparatus.

[0019]

EFFECTS OF THE INVENTION In a semiconductor manufacturing apparatus, it is possible to remove deposits attached to the inside by a relatively inexpensive means without exposing the apparatus to the atmosphere. Therefore, the operating rate of the device is improved, and the production cost can be reduced.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of an embodiment of a processing chamber.

FIG. 2 is an explanatory view of an embodiment of a bell jar and a base chamber.

FIG. 3 is an explanatory diagram of an example of an insulating coating and a conductive coating.

[Explanation of symbols]

11 ... Quartz window, 12 ... Bell jar, 13 ... Base chamber, 14 ... Gas supply pipe, 15 ... Insulating joint, 21 ... Insulating plate, 22 ... O ring, 31 ... Insulating coating, 32 ... Conductive coating.

Claims (1)

[Claims] 1. A semiconductor manufacturing apparatus comprising a processing chamber and means for causing a chemical or physical action inside the processing chamber, by applying a voltage to the whole or a part of the processing chamber. A semiconductor manufacturing apparatus characterized by removing or reducing attached substances generated therein by chemical or physical action.