JP3067312B2 - Thin film forming equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin film forming apparatus used for forming a thin film on an object to be processed in a process of manufacturing a semiconductor product or an electronic component.

[0002]

2. Description of the Related Art In a semiconductor product manufacturing process, a low-pressure CVD apparatus or a plasma CVD apparatus has been put into practical use as an apparatus for forming a film such as a poly-Si film, a silicon nitride film, and a silicon oxide film on the surface of an object to be processed. .

As shown in FIG. 2, a low pressure CVD apparatus comprises a reaction chamber 31, a heater 32 for heating the inside of the reaction chamber 31,
A furnace port flange 33 provided below the reaction chamber 31;
A raw material gas supply system 34 connected to a furnace port flange 33 and an exhaust system 35 connected to the top of the reaction chamber 31 are provided. A quartz boat 36 on which a large number of workpieces are mounted is placed at a predetermined position in the reaction chamber 31. And the reaction chamber is supplied with SiH4, SiH2Cl2 from the source gas supply system 34 under reduced pressure and heating.
And a source gas such as NH3 to form a reaction product film such as a poly-Si film or a silicon nitride film on the surface of the object to be processed.

[0004]

By the way, the vacuum exhaust means 39 connected to the exhaust system 35 of such a conventional low pressure CVD apparatus is basically a reaction pump comprising a mechanical booster pump and a vacuum pump of a rotary pump. When the product and the rest of the raw material gas used for the reaction are exhausted, a part of the exhaust gas is trapped in the trap of the exhaust system 35.
Solids accumulate as solids in the vacuum pump, which lowers the exhaust capacity and deteriorates oil in the vacuum pump, thereby shortening the maintenance period.

An object of the present invention is to solve the above-mentioned conventional problems, and an object of the present invention is to provide a thin film forming apparatus in which the remaining of reaction products and raw material gas are reduced from being accumulated in a vacuum pump.

[0006]

According to the present invention, there is provided a thin film forming apparatus for supplying a reaction gas into a reaction chamber to process an object to be processed and exhausting exhaust gas by an exhaust system, wherein the reaction gas is introduced into the exhaust system. It is characterized by comprising a gas introduction system and a plasma processing chamber provided with a plasma generating electrode.

[0007]

According to the present invention, an exhaust system is provided with a plasma processing chamber, a reaction gas is introduced into the plasma processing chamber, and the reaction gas is activated by plasma and reacts with the exhaust gas to become a stable gas. Since the gas is evacuated, it is possible to reduce accumulation of reaction products and reaction gas in the vacuum pump.

[0008]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 schematically shows a main part of a thin film forming apparatus according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

In FIG. 1, 21 is a reaction chamber, 22 is a heater for heating the inside of the reaction chamber 21, 23 is a furnace port flange, 24 is a source gas supply system, 25 is an exhaust system, and 26 is a large number of workpieces. , A reaction gas introduction system 27, and a vacuum evacuation means 29, such as a mechanical booster pump, a rotary pump, and a trap.

The operation of the thin film forming apparatus configured as described above will be described below.

First, a quartz boat 26 on which a large number of objects to be processed (for example, silicon wafers) are loaded is stored at a predetermined position in a reaction chamber 21 heated by a heater 22 and then evacuated by a vacuum evacuation means 29. Is evacuated. After the evacuation is completed, the source gas is introduced from the source gas supply system 24 and subjected to a gas phase reaction to deposit a film on the target object. When the gas phase reaction is completed, the introduction of the raw material gas is stopped and the vacuum is evacuated. Then, the boat 26 is moved to the object removal position, and the object is removed from the boat 26, thereby completing the operation.

In the exhaust system 25 of the thin film forming apparatus, a plasma processing chamber 30 provided with a plasma generating electrode is provided.
A reaction gas introduction system 27 for introducing a reaction gas into the plasma processing chamber 30 is connected. While a raw material gas is introduced into the reaction chamber 1 and a film is deposited on the object by a gas phase reaction, a fluoride gas (ClF
3, NF3, CF4) is introduced into the plasma processing chamber 30 for 5 to 20 SCCM. The reaction gas is decomposed and activated by the plasma in the plasma processing chamber 30, reacts with the exhaust gas, and is exhausted as a stable gas. Therefore, it is possible to reduce the accumulation of the reaction product and the remainder of the reaction gas in the vacuum pump. it can.

[0015]

As described above, the present invention comprises a plasma processing chamber provided with a reaction gas introduction system for introducing a reaction gas into an exhaust system in contact with exhaust gas and a plasma generating electrode, and exhaust gas is exhausted as a stable gas. Therefore, it is possible to reduce the accumulation of the reaction products and the residual of the raw material gas in the vacuum pump, and to reduce the possibility of accumulating as a solid in the vacuum pump, lowering the exhaust capacity and causing oil deterioration in the vacuum pump. This has the effect of reducing maintenance.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a thin film forming apparatus schematically showing a main part configuration of an embodiment of the present invention.

FIG. 2 is an explanatory view schematically showing a main part configuration of a conventional thin film forming apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 21 Reaction chamber 22 Heater 23 Furnace opening flange 24 Source gas supply system 25 Exhaust system 26 Quartz boat on which many objects to be processed were loaded 27 Reaction gas introduction system 29 Vacuum exhaust means 30 Plasma processing chamber

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-125876 (JP, A) JP-A-59-223294 (JP, A) JP-A-2-21616 (JP, A) (58) Field (Int.Cl. ⁷ , DB name) H01L 21/205

Claims (1)

(57) [Claims] 1. A reaction chamber, a gas introduction device for introducing a raw material gas for forming a thin film into the reaction chamber, and an exhaust system for introducing a raw material gas into the reaction chamber to process an object to be processed and exhausting exhaust gas. A thin film forming apparatus comprising: a gas introducing device for introducing a reaction gas; and a plasma processing chamber provided with a plasma generating electrode, in an exhaust device that contacts the exhaust gas.