JP3235176B2 - Organic metal compound vaporizer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing thin films of compound semiconductors, dielectrics, superconductors, magnetic materials, etc. by vapor phase growth (MO-CVD) using organometallic compounds as raw materials. The present invention relates to an apparatus for supplying an organometallic compound powder as a solid raw material used as a raw material thereof, and an apparatus for vaporizing and supplying an organometallic compound using the powder supply apparatus.

[0002]

2. Description of the Related Art In recent years, as electronic devices have become smaller, lighter, and higher in performance, many attempts have been made to reduce the thickness of magnetic materials and dielectric materials, and various thin film devices have been studied. . The MO-CVD method, which uses an organometallic compound as a raw material, can produce a large-area thin film at a high speed under a relatively low degree of vacuum. Is excellent.

As a method of introducing a solid organometallic compound into a CVD reactor, a raw material is placed in a closed vessel under reduced pressure, and the whole vessel is heated to vaporize the organometallic compound as a solid raw material. Is introduced by a controlled carrier gas.

FIG. 2 is a simplified diagram of a conventional vaporizing and supplying apparatus according to this method. In the figure, 1 is a carrier gas A
r is a mass flow controller for controlling the flow rate of r, 2 is a vaporizer, 3 is a raw material, 4 is a gas collector, 5 is a valve, 6 is a mixing chamber for mixing raw material gas and O ₂ gas, 7 is an introduction nozzle, 8 is a substrate, 9 is a substrate heater, 10 is a reaction chamber, and 11 is a vacuum pump.

[0005] This device is used as follows. First, several kinds of raw materials 3 are each heated to a predetermined temperature. The valve 5 is opened, and the carrier gas Ar whose flow rate is controlled by the mass flow controller 1 flows into the vaporizer 2 and is mixed with the O ₂ gas in the mixing chamber 6. this,
It is introduced into the reaction chamber 10, which has been depressurized by the vacuum pump 11, through the introduction nozzle 7. Raw material gas and O
_{The two} gases react on the substrate 8 heated by the substrate heater 9 to form a thin film. Such a material supply apparatus for forming a thin film is described in, for example, Applied Physics Letter (1989), pp.1581 to 158.
It is published on page 2.

[0006]

However, when a film is formed using the above-mentioned vaporization supply apparatus, the film thickness and various physical properties vary even when the raw material is vaporized under the same conditions. There is. This is because the organic metal compound as a raw material is deteriorated due to the heat history and the raw material in the vaporizer is gradually reduced, so that the vaporization conditions are changed.

When a film is formed using two or more kinds of organometallic compound raw materials, the vaporization conditions are different from each other, so that a corresponding number of vaporizers are required. Therefore, the apparatus becomes complicated, and it becomes more difficult to keep the vaporization conditions of each raw material constant.

[0008]

In order to solve the above-mentioned problems, the present invention provides a method of supplying one or more kinds of new organometallic compound powders having no heat history at the same supply amount and the same mixing ratio. An object of the present invention is to provide a powder supply device capable of vaporizing an organometallic compound powder supplied by the powder supply device under the same conditions and transporting the powder to a reactor.

[0009]

Therefore, according to the present invention, the organometallic compound as a raw material is deteriorated due to the thermal history, the vaporization condition changes due to the decrease in the raw material in the vaporizer, or the mixing ratio when two or more raw materials are used. Since there is no change, a thin film having the same characteristic value can always be obtained under the same conditions.

[0010]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view of an embodiment of the present invention.

FIG. 1 is a schematic diagram showing an apparatus for supplying a powder of an organometallic compound and an apparatus for vaporizing an organic metal compound according to an embodiment of the present invention.

In FIG. 1, 12 is a mass flow controller for controlling the flow rate of a carrier gas, 13 is a valve for controlling the introduction of a carrier gas into a vaporization chamber 20,
14 is a container of the powder of the organometallic compound, 15 is the powder of the organometallic compound as a raw material, 16 is a vibrator, 17 is a shutter for controlling the introduction of the organometallic compound powder 15 into the vaporization chamber 20, and 18 is the organometallic compound. Powder 1
5 is a nozzle for introducing 5 onto the plate 21, 19 is a bypass for keeping the inside of the container 14 of the organometallic compound powder at the same degree of vacuum as in the vaporization chamber 20, 20 is the vaporization chamber, 21 is the plate, and 22 is the plate 21 A heater for heating; 23, a controller for controlling the temperature of the plate 21; 24, a motor for rotating the plate 21;
Numeral 5 is a container for collecting the scraped powder, 26 is a scraping rod for scraping off the powder remaining on the plate 21, 27 is a chamber for a gas reservoir, 28 is a valve for controlling the flow of a bypass 29, and 29 is a gas reservoir. A bypass between the chamber 27 and the vacuum pump 35, a valve 30 for controlling a gas flow between the gas reservoir chamber 27 and the CVD reactor 33, a substrate 31, a substrate heater 32,
3 is a CVD reactor (for example, a thermal CVD reactor), 34
Is a leak valve for breaking the vacuum of the CVD reactor 33, 35
Is a valve for controlling the flow of gas between the CVD reactor 33 and the vacuum pump 36, 36 is a vacuum pump, and 37 is a heater for heating each chamber and a pipe between them. However, the organometallic compound powder supply device is not heated.

This device operates as follows. First
Powder of organometallic compound as raw material (if two or more
Mix well to a certain mixing ratio) and fill in powder container 14
You. Next, the plate 21 is connected to the temperature control controller 2.
The heater 22 controlled by the heater 3 controls a predetermined temperature (yes).
Sublimation in a short time, much higher than the sublimation temperature of metal compounds
To the substrate heater 32)
The substrate 31 set on the heater is heated to a predetermined temperature.
Heat to In addition, the sublimed raw material is re-
In order to prevent solidification and coagulation, heater 37
And a pipe between them at a predetermined temperature (sublimation of organometallic compound)
(Slightly higher than the temperature). Close valve 34
And valves 13, 28, 30, and 35 are opened to reduce the pressure inside the system.
I do. Next, the valves 30 and 35 are closed, and the CVD reactor
The inside of 33 is kept under vacuum and separated from the gas flow. Soshi
Then, the plate 21 is rotated by the motor 24,
Open the heater 17 and use the vibrator 16 to
The powder of the genus compound is put on the plate 21 through the nozzle 18
While supplying, a predetermined flow is
Flow carrier gas. Organic dropped on plate 21
The metal powder is vaporized on the plate 21 heated to a high temperature.
Gas chamber with a carrier gas
27 to the vacuum pump 36 via the bypass 29
Devour. The powder remaining on the plate 21 is scraped off.
The rod 26 is scraped from the plate 21 into the container 25.
It is scraped off and the plate 21 is always kept clean. I
After leaving for a while, the supply of raw material gas becomes stable and gas
Source gas is sufficiently accumulated in the chamber 27 for
Pulsation of the concentration of the source gas due to
At this point, the valves 30 and 35 are opened and the valve 28 is opened.
Is closed, and the raw material gas and the reactive gas
(Eg O _Two) To start film formation on the substrate 31
You. After a predetermined time has passed, the valves 30 and 35 are closed.
First, the valve 28 is opened, and the inside of the CVD
From the gas stream. After that, open the leak valve 34
Breaks the vacuum inside the CVD reactor 33 and replaces the substrate.
Then, the next film formation is performed while maintaining the constant supply of the source gas.
Can be done.

In this embodiment, the thermal CVD is used as the CVD reactor.
Needless to say, the same effect can be obtained in the VD method, the photo CVD method, and the like.

[0015]

As described above, the present invention provides a vaporization chamber.
On a rotating plate heated to high temperature installed in the
Then, the powder of the organometallic compound is supplied and vaporized.
Along with the carrier gas introduced into the vaporization chamber,
While feeding into the reactor for forming the film, the plate
It was left on the plate by the scraper stick provided above.
Organometallic compounds characterized by removing unvaporized powder
It is a device for vaporizing and supplying things. Scraping provided on plate
Remove the unvaporized powder remaining on the plate with a dropper.
By removing it, the surface of the plate is kept clean, so that a thin film having the same characteristic value can always be obtained under the same conditions, which is extremely advantageous in practical use.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an organic metal compound powder supply device and a vaporization supply device according to one embodiment of the present invention.

FIG. 2 is a simplified configuration diagram of a conventional organic metal compound vaporization supply device.

[Explanation of symbols]

 Reference Signs List 12 mass flow controller 13 valve 14 powder container 15 powder of organometallic compound 16 vibrator 17 shutter 18 introduction nozzle 19 bypass 20 vaporization chamber 21 plate 22 heater 23 controller 24 motor 25 container 26 scraper rod 27 chamber for gas reservoir 28 valve 29 bypass Reference Signs List 30 valve 31 substrate 32 substrate heater 33 CVD reactor 34 leak valve 35 valve 36 vacuum pump 37 heater

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Eiji Fujii 1006 Kadoma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) References JP-A-60-130820 (JP, A) JP-A-3-3 287768 (JP, A) JP-A-48-12287 (JP, A) JP-A-3-158457 (JP, A) JP-A-59-191324 (JP, A) JP-A-62-174912 (JP, A) (58) Field surveyed (Int.Cl. ⁷ , DB name) C23C 16/00-16/56 B65D 88/66 H01L 21/205 H01L 21/31

Claims (5)

(57) [Claims] 1. An organic metal compound powder is supplied to a rotating plate heated in a vaporization chamber and heated to a high temperature and vaporized, and a thin film is formed together with a carrier gas introduced into the vaporization chamber. An organic metal compound vaporization supply apparatus, characterized in that unremoved powder remaining on the plate is removed by a scraping bar provided on the plate while supplying the mixture into the reaction apparatus. 2. The apparatus for vaporizing and supplying an organometallic compound according to claim 1, further comprising a powder supply apparatus for supplying a fixed amount of the powder by vibrating a container filled with the powder of the organometallic compound. 3. A gas reservoir chamber for suppressing pulsation of the concentration of a source gas between a vaporization chamber and a reactor for forming a thin film, wherein the entire gas path is heated. Item 4. An apparatus for vaporizing and supplying an organometallic compound according to Item 1 or 2 . 4. The apparatus for vaporizing and supplying an organometallic compound according to claim 3, wherein the whole of the apparatus for supplying a powder of the organometallic compound, the vaporization chamber and the gas reservoir are kept under reduced pressure. 5. A vaporization chamber is connected to the downstream side of the powder container, a rotating plate heated to a high temperature is provided in the vaporization chamber, and a scraping rod is provided in contact with the plate, and a downstream side of the vaporization chamber is provided. A gas chamber is connected to the side, a CVD reactor is connected to the downstream side of the gas chamber, and an organometallic compound is supplied from the powder container to a plate in the vaporization chamber to be vaporized. The organic metal compound vaporized while removing the unsublimated powder remaining in the above with the scraping rod and the carrier gas introduced into the vaporization chamber are mixed with the C.
An organic metal compound vaporizer for supply into the VD reactor.