JP3317940B2 - Cleaning equipment for plasma CVD 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 cleaning apparatus for a plasma CVD apparatus, and more particularly to a plasma CV after film formation.
The present invention relates to a structure of a cleaning device having improved cleaning performance in a reaction chamber of a device D.

[0002]

2. Description of the Related Art A plasma CVD apparatus is widely used as an apparatus for depositing a thin film such as a silicon oxide film or a silicon nitride film on a semiconductor device. accumulate. The film deposited on the wall of the reaction chamber is peeled off and re-attached to the surface of the semiconductor device, which affects the production yield and quality of the semiconductor device.
No. 863 discloses a method of circulating hot water whose temperature is controlled on the side wall of a reaction chamber of a plasma CVD apparatus to reduce the deposition of a film on the side wall as much as possible. A cleaning gas (fluorine radical) activated by connecting a cleaning device is introduced into a reaction chamber to etch a deposited film on a wall of the reaction chamber.

FIG. 4 is a schematic diagram of a cleaning apparatus connected to a conventional plasma CVD apparatus. In the drawing, reference numeral 1 denotes a reaction chamber of the plasma CVD apparatus, and 4 denotes an introduction pipe connected to the reaction chamber 1 of the plasma CVD apparatus. After the conductor device on which the film is formed is taken out, the cleaning activated through the introduction pipe 4 is performed. Gas is introduced into the reaction chamber 1 of the plasma CVD apparatus, the film (not shown) attached to the wall (not shown) of the reaction chamber 1 of the plasma CVD apparatus is etched, and the inside of the reaction chamber 1 of the plasma CVD apparatus is cleaned. Is done. Reference numeral 3 denotes a fluorine radical generator, and reference numeral 2 denotes a microwave generator connected to the fluorine radical generator 3 for generating microwaves. The fluorine-containing cleaning gas (such as CF 4) introduced into the fluorine radical generator 3 absorbs microwaves generated from the microwave generator 2 to generate fluorine radicals. The fluorine radicals are introduced from the introduction pipe 4 into the reaction chamber 1 of the plasma CVD apparatus, and the film deposited on the wall of the reaction chamber 1 of the plasma CVD apparatus is removed by etching. A water supply (not shown) of cooling water such as pure water is provided in the wall of the fluorine radical generator 3, and a hose 6 is connected to the water supply from the outside to circulate pure water at normal temperature to fluorine. It controls the radical generator wall temperature from rising too high.

[0004]

In the conventional plasma CVD apparatus shown in FIG. 4, in order to control the temperature rise of the wall of the fluorine radical generator 3, pure water at normal temperature is supplied to a water supply provided in the wall. When circulating pure water at normal temperature, the temperature of the wall of the fluorine radical generator 3 is locally lowered, and the energy of the fluorine radicals generated by the absorption of microwaves is taken away. However, there is a problem that the etching rate of the deposited film on the wall is reduced and the deposited film remains. The deposited film remaining without being etched on the wall of the reaction chamber 1 of the plasma CVD apparatus is eventually separated from the wall and re-attached on the semiconductor Si film, which contributes to quality problems such as particles remaining in semiconductor device manufacturing. .

The inventor of the present invention provided a water supply on the wall of the fluorine radical generator and the introduction pipe 4, and circulated hot pure water whose temperature was controlled to suppress a decrease in the activity of the fluorine radical. The present inventors have found that the deposited film on the wall of the chamber is effectively etched, and that the deposited film can be prevented from being left unetched.

[0006]

Means for Solving the Problems Plasma CVD of the present invention
The apparatus cleaning apparatus is connected to the plasma CVD apparatus reaction chamber, has first temperature control means for controlling the temperature of the wall inside the tube wall, and an introduction pipe for introducing fluorine radicals into the reaction chamber. A fluorine radical generator connected to the introduction pipe and having second temperature control means in the vessel wall for controlling the temperature of the vessel wall, and irradiating the fluorine-containing cleaning gas with microwave by irradiating the fluorine-containing cleaning gas with microwaves; together and constituted by a microwave generator to generate radicals, and the heat exchanger connected to said first and second temperature control means
The temperature of the tube wall and the vessel wall is controlled to 45 to 60 ° C.
It is characterized by being controlled.

In the above configuration of the present invention, the first and second temperature control means may be connected to the same heat exchanger, or may be connected to different heat exchangers.

The first and second temperature control means in the configuration of the present invention are provided for circulating hot pure water in the tube wall of the introduction tube and in the container wall of the fluorine radical generator. Circulating warm pure water can be used.

[0009]

In the present invention, the fluorine radical is converted into plasma C
By controlling the temperature of the wall of the fluorine radical generator which introduces a fluorine-containing cleaning gas into the VD device reaction chamber and the fluorine-containing cleaning gas which is activated by absorbing microwaves to generate fluorine radicals, at 45 to 60 ° C. Suppress the energy decrease of the fluorine radicals that collided with these walls,
Since the deposited film deposited by the CVD reaction on the wall of the reaction chamber of the plasma CVD apparatus can be removed by etching at a stable rate and cleaned, the deterioration of the quality of the semiconductor device due to particles in the plasma CVD apparatus can be prevented.

[0011]

Next, a cleaning apparatus for a plasma CVD apparatus according to an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic configuration diagram of a cleaning apparatus for a plasma CVD apparatus according to a first embodiment of the present invention.

A cleaning apparatus for a plasma CVD apparatus according to the present invention is connected to a reaction chamber 1 of a plasma CVD apparatus, and has a wall for circulating hot pure water whose temperature is controlled as first temperature control means. And a supply pipe 4 for introducing fluorine radicals for etching into the reaction chamber 1 of the plasma CVD apparatus. The supply pipe 4 is connected to the supply pipe 4 and has a second temperature control means on its wall. A fluorine-radical generator 3 for generating fluorine radicals from the introduced fluorine-containing cleaning gas having a circulating-temperature pure water flow system, and microwave irradiation for the fluorine-containing cleaning gas introduced into the fluorine-radical generator 3 , And a heat exchanger 5 for controlling the temperature of the hot pure water.

The heat exchanger 5 includes a circulating hot pure water tank 12 provided with a heater 19 as a storage tank for hot pure water.
A circulation pump connected to the circulation path of hot pure water for sending hot pure water to the introduction pipe 4, a temperature sensor 9 installed in the circulation path of hot pure water, and a heater 19 and a cooling water based on the temperature measured by the temperature sensor 9. It comprises a temperature controller 10 for controlling the temperature of the hot pure water by adjusting the valve 11 and a flow meter 7 provided in a circulation path of the hot pure water to check the circulation amount of the hot pure water. The circulation path of the hot pure water of the heat exchanger 5 is connected to the inlet pipe 4 and a joint (not shown) of the hot pure water flow of the fluorine radical generator 3 by a hose 6a and a hose 6c, respectively. In addition, the inlet pipe 4 and the water supply of the fluorine radical generator 3 are connected by a hose 6b.

The temperature of the circulating hot pure water is sensed by a temperature sensor 9 of a temperature controller 10 installed in a hot pure water circulating path. If the temperature is lower than a predetermined temperature, a heater 12 in a circulating tank is operated. If the temperature is higher than the predetermined temperature, the valve is opened to open the cooling water (normal temperature) pipe, and the cooling water is added to the inside of the circulation tank to lower the temperature so that the temperature is controlled to the predetermined temperature. In this way, by circulating the temperature-controlled hot pure water through the inlet pipe 4 and the wall of the fluorine radical generator 3, the temperature of the inlet pipe 4 and the wall of the fluorine radical generator 3 can be controlled to a predetermined temperature, and Even when the generated fluorine radicals collide with these walls, it is possible to suppress a decrease in the energy of the fluorine radicals. As a result, the deposited film deposited on the wall of the reaction chamber of the plasma CVD apparatus can be removed by etching at a stable rate.

FIG. 2 is a detailed sectional view of the introduction pipe and the fluorine radical generator of FIG. As shown in FIG. 2, the fluorine radical generator 3 and the introduction pipe 4 are provided with a circulating hot pure water passage 14 for flowing circulating warm pure water, and the circulating warm pure water passage 14 therebetween is connected by a hose 6b. ing. The hot pure water circulated from the heat exchanger enters the water supply of the introduction pipe 4 via the hose 6a, enters the water supply 14 of the fluorine radical generator 3 via the hose 6b, and the water supply of the fluorine radical generator. Is returned to the circulating-temperature pure water tank 12 (see FIG. 1) of the heat exchanger 5 via the hose 6c connected to the heat exchanger 5.

The fluorine radical generator 3 comprises a vacuum chamber 16 having an inner wall formed of a sapphire tube 18 and an outer wall formed of a quartz tube 17, and a circulating hot pure water passage 14 for flowing hot pure water between the quartz tube 17 and the sapphire tube 18. Is provided. In the figure, reference numeral 13 denotes a fluorine rubber O-ring, and reference numeral 15 denotes a radical generator housing. The introduction pipe 4 is made of an Al base material. A circulating-temperature pure water flow system 14 is provided in the wall.

In the conventional cleaning apparatus for a plasma CVD apparatus shown in FIG. 3, when a cleaning gas such as CF4 gas is used, the etching rate of the silicon nitride film deposited on the wall of the reaction chamber is 200 to 250 nm / min ( Although the circulation rate of pure water at room temperature was 35 l / min, the etching rate of the cleaning apparatus for a plasma CVD apparatus of the present invention shown in FIG. 1 was 250 to 300 nm / min (circulation rate of hot pure water (45 ° C.): 35 l). / Min), which was confirmed to be higher than before.

In the present invention, the temperature of the circulating hot pure water is suitably from 45 to 60 ° C., and when the temperature falls below 45 ° C. or becomes higher than 60 ° C., the temperature control accuracy of the circulating hot pure water decreases. The circulation amount of hot pure water is 10 to 40 l
/ Min. In FIG. 1, the circulation direction of the hot pure water of the introduction pipe 4 and the fluorine radical generator 3 is the direction of entering from the upper part of the introduction pipe 4, exiting from the lower part of the fluorine radical generator 3, and returning to the heat exchanger 5. And vice versa.

Next, a cleaning apparatus for a plasma CVD apparatus according to a second embodiment of the present invention will be described with reference to the drawings. FIG. 3 is a schematic configuration diagram of a cleaning apparatus for a plasma CVD apparatus according to a second embodiment of the present invention. In the present embodiment, the temperature control of the hot pure water circulating through the fluorine radical introduction pipe 4 and the fluorine radical generator 3 is performed separately by the two heat exchangers 5 and 5a having the same structure. By separately controlling the temperature of the hot water of the fluorine radical introducing tube 4 and the fluorine radical generator 3, the temperature of the fluorine radical can be controlled more accurately, and the film deposited on the wall of the reaction chamber of the plasma CVD device can be more stabilized. Can be etched at a speed. In FIG. 3, the same reference numerals as those in FIG. 1 mean the same as those in FIG. Further, reference numerals 20, 2 in FIG.
Reference numeral 1 denotes a hose that connects the hot pure water circulation path of the heat exchanger 5 and the circulation hot pure water supply water path of the introduction pipe 4. Is a hose that connects Heat exchanger 5a
Temperature controller 10a, temperature sensor 9a, circulation pump 8a,
Flow meter 7a, heater 19a, circulation temperature pure water tank 1
2a and the valve 11a are the same as the corresponding components of the heat exchanger 5.

[0020]

As described above, in the cleaning apparatus for a plasma CVD apparatus according to the present invention, a circulating hot pure water channel is provided on the inlet pipe and the wall of the fluorine radical generator, and the temperature-controlled hot pure water is circulated therein. Thereby, the following effects can be obtained. Since the temperature of the inlet tube and the wall of the fluorine radical generator is kept at a predetermined temperature and does not locally become low, it is possible to suppress a decrease in the energy of the fluorine radical colliding with these walls and to reduce the plasma C
There is an effect that the deposited film on the wall of the VD apparatus reaction chamber can be removed by etching at a stable rate. Since the deposited film on the wall of the reaction chamber of the plasma CVD apparatus can be completely removed, it is possible to prevent quality deterioration due to particles of the semiconductor device.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a cleaning apparatus for a plasma CVD apparatus according to a first embodiment of the present invention.

FIG. 2 is a detailed sectional view of the introduction tube and the fluorine radical generator of FIG.

FIG. 3 is a schematic configuration diagram of a cleaning apparatus for a plasma CVD apparatus according to a second embodiment of the present invention.

FIG. 4 is a schematic view of the configuration of a conventional plasma CVD apparatus.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Plasma CVD apparatus reaction chamber 2 Microwave generator 3 Fluorine radical generator 4 Introducing pipe 5,5a Heat exchanger 6,6a, 6b, 6c, 20,21,22,23 Hose 7,7a Flowmeter 8,8a Circulation Pump 9 Temperature sensor 10, 10a Temperature controller 11, 11a Valve 12, 12a Circulating hot pure water tank 13 Fluoro rubber O-ring 14 Circulating hot pure water water supply 15 Radical generator housing 16 Vacuum chamber 17 Quartz tube 18 Sapphire tube 19 Heating heater

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01L 21/31 C23C 16/44 H01L 21/3065 H05H 1/46

Claims (6)

(57) [Claims] 1. A plasma CVD apparatus connected to a reaction chamber,
A first temperature control means for controlling the temperature of the wall inside the pipe wall, an introduction pipe for introducing fluorine radicals into the reaction chamber, and a temperature of the vessel wall connected to the introduction pipe and inside the vessel wall; A fluorine radical generator having second temperature control means for controlling the temperature, a microwave generator connected to the generator to irradiate a fluorine-containing cleaning gas with microwaves to generate fluorine radicals, together comprised the heat exchanger and connected to the second temperature control means, said pipe
A cleaning apparatus for a plasma CVD apparatus, wherein the temperature of the wall and the vessel wall is controlled to 45 to 60C . 2. The cleaning apparatus for a plasma CVD apparatus according to claim 1, wherein said first and second temperature control means are connected to different heat exchangers. 3. A circulation provided as said first and second temperature control means for circulating hot pure water at a predetermined temperature in said pipe wall of said introduction pipe and in said vessel wall of said fluorine radical generator. 3. The cleaning apparatus for a plasma CVD apparatus according to claim 1, wherein a hot pure water flow is used. Wherein said inlet pipe is composed of an aluminum base material, the plasma CVD apparatus cleaning device according to claim 3, characterized in that the circulating warm pure Mizudori water into the tube wall is provided. 5. The method according to claim 1, wherein the fluorine radical generator comprises a vacuum chamber having a sapphire tube on the inside and a quartz tube on the outside, and the circulating pure water supply water is provided between the sapphire tube and the quartz tube. The cleaning apparatus for a plasma CVD apparatus according to claim 3, wherein 6. A plasma CVD apparatus connected to a reaction chamber,
First temperature control means for controlling the temperature of the wall in the tube wall is provided.
And an introduction pipe for introducing fluorine radicals into the reaction chamber.
And connected to the introduction pipe to control the temperature of the vessel wall inside the vessel wall
Radical generator having second temperature control means
And a fluorine-containing cleaning gas connected to the generator.
Microwave irradiation to generate fluorine radicals
And the first and second temperature control means.
And a heat exchanger connected thereto .
The pipe of the inlet pipe as first and second temperature control means
In the wall and in the vessel wall of the fluorine radical generator
Circulating pure water provided to circulate hot pure water at a constant temperature
A cleaning apparatus for a plasma CVD apparatus , wherein a water-flow water supply system is used, and the introduction pipe is made of an aluminum base material, and the circulating-temperature pure water water supply path is provided in the pipe wall.