JPH0355832A - Semiconductor production device - Google Patents

Abstract

PURPOSE:To gasify a reaction product generated through sputtering, to prevent the adhesion of the reaction product onto a wall surface in a reaction tube and to obviate the generation of a defective semiconductor device by installing a pair of second electrode plates so as to surround the peripheries of a pair of first electrode plates in the same reaction tube and generating plasma by the second electrode plates. CONSTITUTION:A reaction tube 103 housing a semiconductor substrate 108, a pair of first electrode plates 104 being mounted into the reaction tube 103 and having an anode 104a and a cathode 104b, a pair of second electrode plates 105 being set up so as to surround the peripheries of the first electrode plates 104 and having anodes 105a and cathodes 105b, a plurality of reaction gases injected into the reaction tube 103 to which the first electrode plates 104 and the second electrode plates 105 are fitted, and high-frequency power supplies 107a, 107b applying an electric field to the first electrode plates 104 and the second electrode plates 105 and generating plasma in said reaction gases are provided. Oxygen gas is introduced from a second etching-gas introducing port 101b, and a second plasma region 109b in which oxygen gas is changed into plasma, is generated between the second anode plate 105a and the second cathode plate 105b.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a semiconductor manufacturing apparatus for etching.

(Prior Art) Some conventional etching apparatuses perform etching using sputtering, and when a semiconductor substrate is etched, reaction products are generated and adhere to the walls of the reaction tube.

A conventional sputter etching apparatus will be described below with reference to FIG. First, in a reaction tube (203) having an etching gas inlet (201) and an exhaust port (202>), for example, an anode plate (206a) and a cathode plate (202) are placed as parallel plate electrodes.
06b) are provided in pairs. Anode plate (206a
) is grounded outside the reaction tube (203), and the cathode plate (2
06b) High frequency electricity (207) outside the reaction tube (203)
2 are connected. A semiconductor substrate (208) is provided on the cathode plate (208b).

According to the above configuration, as an etching method, first, a vacuum pump is used from the exhaust port (202) of the reaction tube (203) to bring the inside of the reaction tube (203) into a vacuum state. Next, Ar gas is introduced as a reaction gas from the etching gas inlet (201). After this, the anode plate (208a) and the cathode plate (208a)
A high frequency electric field is applied by the high frequency power source (207) between the
209) occurs. A by plasma region (209)
Etching is performed by the r+ ions colliding with a polyimide film (not shown) formed on the semiconductor substrate (2H). At this time, reaction products released from the semiconductor substrate (208) adhere to the wall inside the reaction tube (203). After etching, the semiconductor substrate (208) is transferred to another reaction tube into which Ar gas is similarly injected, for example, and the Ar gas in the reaction tube is exhausted and the semiconductor substrate (208)
8) is taken out.

Etching can be performed in this way, but Ar
A reaction product, which is a carbonized organic substance, is generated from the semiconductor substrate (208) due to the collision of ions, and this may adhere to the wall surface inside the reaction tube (203). Reaction products adhering to the wall inside the reaction tube (203) may peel off, causing dust generation.

Therefore, if this dust adheres to the semiconductor substrate (208), problems such as poor contact and poor conduction will occur in the semiconductor device.

(Problems to be Solved by the Invention) As detailed above, in the past, the reaction products adhering to the wall inside the reaction tube were peeled off by sputtering.
This sometimes adheres to the semiconductor substrate, causing defects in the semiconductor device.

An object of the present invention is to gasify the reaction products generated by sputtering, thereby preventing the reaction products from adhering to the wall surface of the reaction tube and thereby preventing the occurrence of defects in semiconductor devices.

[Structure of the invention]

(Means for Solving the Problems) According to the present invention, a reaction tube that accommodates a semiconductor substrate, a pair of first electrode plates provided in the reaction tube and having an anode and a cathode, and a pair of second electrode plates surrounding the periphery and having an anode and a cathode; a plurality of reaction gases injected into the reaction tube in which the first electrode plate and the second electrode plate are provided; , the first electrode plate, and a high frequency power source that applies an electric field to the second electrode plate to generate plasma in the reaction gas.

(Function) According to the above configuration, a pair of second electrode plates are provided in the same reaction tube so as to surround a pair of first electrode plates, and plasma is generated by the second electrode plate, and ionized substances and By reacting with the reaction products generated by sputtering and gasifying them, it is possible to prevent the reaction products from adhering to the wall surface inside the reaction tube.

(Example) Hereinafter, an example of the present invention will be described using FIG. 1.

First, the first etching gas inlet (101a), the second etching gas inlet
Etching gas inlet (10lb) and exhaust port (1
02), a first anode plate (104a) and a first
Cathode plates (104b) are provided in pairs. The first anode plate (104a) is grounded outside the reaction tube (103), and the first cathode plate (104b) is connected to a first high frequency power source (IOTA) outside the reaction tube (103). moreover,
Inside the reaction tube (103) are a second anode plate (105a) and a second anode plate (105a).
The cathode plate (105b) is paired with the first anode plate (104a).
) and the first cathode plate (104b). The second anode plate (105a) is the reaction tube (103)
It is grounded outside, and the second cathode plate (105b) is connected to a second high frequency power source (107b) outside the reaction tube (103). On the first cathode plate (104b) is a semiconductor substrate (i
oa) is provided.

According to the above configuration, this etching method first uses a vacuum bomb from the exhaust port (102) of the reaction tube (103) to bring the inside of the reaction tube (103) into a vacuum state. Next, Ar is introduced as a reaction gas from the first etching gas inlet (101a).
Gas is introduced. At this time, oxygen gas is introduced from the second etching gas inlet (10 lb). Next, a high frequency electric field is applied between the first anode plate (104a) and the first cathode plate (104b) by the first high frequency power source (107a), and the Ar gas is turned into plasma and the first plasma region (104b) is
9a) occurs. At the same time, a second high-frequency power source is connected between the second anode plate (105a) and the second cathode plate (105b), which are provided so as to surround the first anode plate (104a) and the first cathode plate (104b). A high frequency electric field is applied by (107b), oxygen gas is turned into plasma, and the second plasma region (
109b) occurs. At this time, the first anode plate (104
Ar" ions collide with the polyimide film on the surface of the semiconductor substrate (10g) provided on a) and the first cathode plate (104b) to perform etching. Organic matter carbonized by etching is etched from the semiconductor substrate (10g). A certain reaction product is generated, but the second anode plate (105a) and the second cathode plate (
105b) and this reaction product reacts and is gasified to mainly generate CO 2 gas. After this, CO2 gas etc. 2 is exhausted from the exhaust port (102).

Therefore, the reaction product and oxygen react and are gasified, so that it is possible to prevent the reaction product from adhering to the wall surface inside the reaction tube (103). Therefore, the reaction products attached to the wall surface inside the reaction tube (103) will not peel off and will not adhere as dust on the semiconductor substrate (108), resulting in defects in the semiconductor device such as poor contact and poor conduction. can be prevented.

[Effects of the Invention] According to the present invention, reaction products adhering to the wall surface of the reaction tube can be gasified without adhering to the wall surface, so it is possible to prevent defects from occurring in semiconductor devices. .

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a sputtering apparatus in an embodiment of the present invention, and FIG. 2 is a block diagram showing a sputtering apparatus in a conventional example. First etching gas inlet...101a, second etching gas inlet...10lb, etching●
Gas inlet・・・・・・・・・・・・201、Exhaust port・
・・・・・・・・・・・・・・・・・・・・・・・・
・・・・・・・・・102, 202, Reaction tube...
・・・・・・・・・・・・・・・・・・・・・・・・
......103, 203, first anode plate...
・・・・・・・・・・・・・・・・・・・・・・・・
・104a, first cathode plate・・・・・・・・・・・・・・・
・・・・・・・・・・・・・・・・・・104b, 2nd anode plate・・・・・・・・・・・・・・・・・・・・・
・・・・・・105a, second cathode plate・・・・・・・・・
・・・・・・・・・・・・・・・・・・・・・ l05b
, Anode plate・・・・・・・・・・・・・・・・・・・・・
・・・・・・・・・・・・・・・206a, Cathode plate...
・・・・・・・・・・・・・・・・・・・・・・・・
......208b, first high frequency power supply...
・・・・・・・・・・・・・・・・・・107a,
Second high frequency power supply・・・・・・・・・・・・・・・・・・
・・・・・・107b, High frequency power supply・・・・・・・・・
・・・・・・・・・・・・・・・・・・・・・207,
Semiconductor substrate・・・・・・・・・・・・・・・・・・・・・
・・・・・・・・・・・・108, First plasma region...
・・・・・・・・・・・・・・・・・・109a, 2nd
Plasma area・・・・・・・・・・・・・・・・・・
・・・l09b, Plasma area・・・・・・・・・・・・
・・・・・・・・・・・・・・・209. 208

Claims (1)

[Claims] a reaction tube accommodating a semiconductor substrate; a pair of first electrode plates provided in the reaction tube and having an anode and a cathode; and a first electrode plate provided surrounding the first electrode plate and having an anode and a cathode. A plurality of reaction gases injected into the reaction tube provided with a pair of second electrode plates, the first electrode plate, and the second electrode plate, the first electrode plate, and the second electrode plate. A semiconductor device comprising: a high frequency power source that applies an electric field to generate plasma in the reaction gas.