JPS59142840A - Vapor deposition device - Google Patents

Abstract

PURPOSE:To enable long-term and satisfactory production of a film deposited by evaporation without film contamination by making it possible to suppress the emission of a filament material of an electron beam generator into a vapor deposition vessel and to prevent the early disconnection of the filament without contaminating the filament. CONSTITUTION:A base body 1 for vapor deposition and an evaporating source 2 are disposed in an evaporating vessel 3 and an introducing pipe 6 for introducing modifying gas is provided by connecting the outlet thereof to the chamber 3 and further an electron ray generator 10 which irradiates an electron ray to the modifying gas introduced into the vessel 3 is produced. A filament 11, a cover 12 in common use as a lead-out electrode provided so as to enclose the filament 11, and an electron ray exit port 13 disposed at the part opposite to the filament in the cover 12 are provided in the generator 10. As a result, the emission of the filament material in the electron ray generator into the vapor deposition vessel is suppressed and the early disconnection of the filament is prevented without contaminating the filament, whereby the film deposited by evaporation having no contamination with the film is satisfactorily produced over a long period of time.

Description

[Detailed description of the invention] The present invention relates to a vapor deposition apparatus.

In recent years, amorphous silicon (hereinafter referred to as RA-8iJ) has become extremely useful as a constituent material for solar cells, electrophotographic photoreceptors, and the like.

This a-8i can be formed as a thin film by various methods, but it is necessary to introduce hydrogen atoms into this a-8i to seal the dangling bonds, and only then can a large darkness be created. Hydrogen-containing a-8i (hereinafter referred to as "a-8i:f (J))" having resistance and photoconductivity is obtained, and practical application becomes possible.

Conventionally known methods for forming a thin film of a-8i:H include a high frequency ion blating method, a direct current ion blating method, and a method of vapor deposition by introducing ionized or activated hydrogen. The formed thin film is easily contaminated, or the thin film forming conditions are unstable and it is difficult to form a stable and homogeneous thin film, or the introduction of hydrogen atoms into the thin film is uneven and a thin film with good characteristics cannot be formed. It has its drawbacks.

As a method to overcome these drawbacks, hydrogen gas is directly introduced into a vapor deposition tank equipped with a vapor deposition substrate and an evaporation source, and is irradiated with an electron beam to activate or ionize the hydrogen while evaporating from the evaporation source. A method has been developed for depositing silicon onto a deposition substrate.

Generally, an electron beam generator that emits an electron beam is composed of a filament for generating thermionic electrons and an extraction electrode for emitting the thermionic electrons generated from the filament. A positive potential greater than that of the filament is applied to the filament, and the thermoelectrons generated from the filament are drawn out to the extraction electrode to emit an electron beam. When this is used to carry out the method described above, the electron Since the material of the filament of the gun is ejected into the vapor deposition tank, there is a possibility that the material of the filament may be mixed into the vapor deposited film formed on the vapor deposition substrate and contaminate the vapor deposited film, or the evaporation source material may be mixed with the filament. Since the filament adheres to the filament and contaminates the filament, there are disadvantages such as the filament being easily broken, and as a result, it is impossible to obtain a good deposited film without film contamination.

The present invention has been made based on the above-mentioned circumstances, and is capable of suppressing emission of filament material of an electron beam sweater into a vapor deposition tank, and also prevents filament contamination and early breakage of the filament. can be prevented,
The object of the present invention is to provide a vapor deposition apparatus that can successfully produce a vapor-deposited film without film contamination over a long period of time.

The vapor deposition apparatus of the present invention is characterized by a vapor deposition tank, a vapor deposition substrate and an evaporation source arranged in the vapor deposition tank, and an inlet pipe for introducing a modification gas whose outlet is connected to the vapor deposition tank. , an electron beam generator for irradiating an electron beam to a modification gas introduced into the vapor deposition tank, the electron beam generator serving also as a filament and an extraction electrode provided to surround the filament. The present invention comprises a cover and an electron beam exit opening provided at a portion of the cover facing the filament.

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

In the present invention, as shown in FIG. 1, a vacuum pump (not shown) is connected to the Pel jar 3 forming a vapor deposition tank via an exhaust path 8, and the vapor deposition substrate 1 placed inside the Pel jar 3 is heated. A heater 4 for heating and a DC power source 5 for applying a negative DC voltage to the vapor deposition substrate 1 or its rear electrode when the vapor deposition substrate 1 is insulating are provided, and an evaporation source 2 is disposed to face the vapor deposition substrate 1. , an electron beam generator for ionizing or activating the modifying gas introduced into the jiber jar 3 through the introduction pipe 6; 1
Set 0. In this electron beam generator 10, as shown in detail in FIGS. 2 and 3, a cylindrical cover 12 made of stainless steel, for example, which also serves as an extraction electrode, is provided to surround a filament 11 made of, for example, tungsten. In a portion of the cover 12 facing the filament 11, a hole having a size corresponding to the size of the filament 11 is provided to form an electron beam exit port 13, for example.

An insulating material 14 is fitted into the opening at the rear end of the cover 12, and a frame 15 made of stainless steel, for example, having an opening in the center is provided outside the insulating material 14, so that the insulating material 14 and Secure the cover 12. A lead rod 16.16 is provided inside the insulating material 14 and extends through the insulating material 14.
is buried, and both ends of the lead rods 16 and 16 are made to protrude into the cover 12 and outside the central opening of the frame 15. The filament 11 is connected between the inner ends of the lead rods 16.16 that protrude into the cover 12, and an alternating current or direct current is connected between the outer ends of the lead rods 16.16 that protrude outside the central opening of the frame 15. Connect the filament heating power source 17. A water cooling pipe 18 made of copper, for example, is spirally wound and fixed by welding or the like on the outer periphery of the cover 12 so as to be in direct contact therewith. Both ends 19 and 20 of this water cooling pipe 18 extend downward and their legs 21
, 22 also serves as a support for the electron beam generator 10.

The negative side of the DC power source 23 is connected to the one lead rod 16, and the positive side of the DC power source 23 is connected to the cover 12.
The cover 12 is connected to the earth potential.

The electron beam generator 10 is arranged in the Pelger 3 such that, for example, the electron beam emission direction is along the vapor deposition substrate 1 and the electron beam emission port 15 is located near the lower side of the vapor deposition substrate 1. do.

In the above, the vacuum pump to which the exhaust path 8 is connected has the ability to create a vacuum of about 10-4 Torr inside the Pelger 3, and the heater 4 heats the deposition substrate 1 from room temperature to a temperature of 350 to 450°C. those who have the ability to
The DC power supply 5 is capable of applying a negative DC voltage of 0 to -10 KV. The heater 7 of the evaporation source 2 may be of any heating type such as electron gun heating, resistance heating, or induction heating, and if it is not based on sublimation, it must be of a structure to prevent spitting (flying of coarse particles). It is preferable that there be.

In the apparatus configured as described above, a vapor deposited film of a-8i:II is produced in the following manner by using silicon as the evaporation source 2 and hydrogen gas as the modifying gas, for example. That is, the vapor deposition substrate 1 is heated by the heater 4, and the silicon evaporation source 2 is heated by the heater 7 to generate silicon vapor, while hydrogen gas is introduced into the Pel jar 3 through the introduction pipe 6, and this introduction is completed. a-8i in which the hydrogen gas was ionized or activated by an electron beam from an electron beam generator 10, and the silicon vapor was deposited on the vapor deposition substrate 1 together with ionized hydrogen or activated hydrogen to seal the dangling bonds: a-8i: A vapor deposited film of H is produced.

According to the above configuration, since an electric field is formed between the filament 11 and the cover 12 by the DC power supply 23, the cover 12 is brought to the ground potential and acts as an extraction electrode, thereby preventing stains. The electron beam is emitted from the electron beam exit port 13, but since the filament 11 is covered by the cover 12, even if the filament material is emitted from the electron beam exit port 13 to the outside of the electron beam generator 10, it will not be significantly affected. In addition, even if the evaporation source substance enters into the electron beam generator 10 from the electron beam exit port 13, it is very small.
It is possible to prevent radiation from being emitted outside of zero, to prevent contamination of the filament, and to prevent early breakage of the filament, resulting in a stable and good production of a deposited film without film contamination over a long period of time. be able to.

Furthermore, when the electron beam generator 10 is installed so that the electron beam emission direction is along the vapor deposition substrate 1, the modification gas directed toward the vapor deposition substrate 1 can be activated or ionized as a whole, so that the modification gas is uniformly distributed. It can be mixed into the deposited film, and a deposited film with good characteristics can be obtained.

Since the cover 12 also serves as an extraction electrode, the configuration of the electron beam generator 10 is simple, and as a result, the cover 12
In the end, the electron beam generator 10f! : As a result, contamination inside the vapor deposition tank caused by the electron beam generator 10 can be reduced. Also cover 12
Since it only needs to be made of metal, its molding process is easy; for example, the electron beam exit port 13 can be easily formed by punching or the like, and it can also provide relatively high heat resistance. In addition, since the cover 12 itself is an extraction electrode, thermionic electrons from the filament 11 are taken into the cover 12 and the cover 12 generates heat. As in the above embodiment, it is preferable to provide a water cooling pipe 18 in contact with and fixed to the outer periphery of the cover 12, thereby preventing the cover 12 from overheating and thus preventing the cover 12 from becoming a source of contamination. It is possible to prevent this from happening. Also, a part of this water cooling pipe 18 is attached to the leg portion 21.2.
2, it is convenient because it can also be used as an itf support and no other support is required.

As the material of the filament 11, it is preferable to use a metal that has good thermoelectron generation property and has a high melting point of, for example, 2000° C. or higher. Specifically, in addition to tungsten, molybdenum, tantalum, carbon steel, and lanthanum are used. Examples include borides. This filament 1
The size of the electron beam exit port 13 is determined by the size of 1, and the size of the electron beam exit port 13 is, for example, 0.1 in width
~20m+, preferably about 1~10m+. The distance between the filament 11 and the electron beam exit port 13 is approximately 10 cm.

The material of the cover 12 is preferably a metal having a high melting point of 1000° C. or higher, including stainless steel and tl
・] (oxygen-free), iron, brass, heat-resistant aluminum, etc. The material of the frame 15 is also made of the same material as the cover 12.

The filament heating power source 17 (7) is an AC or DC power source with a voltage of 10 volts and a current of 50 amperes, for example.As the DC power source 23, a high voltage power source with a voltage of 3 kilovolts, for example, is used. The amount of thermoelectrons emitted from the electron/string emitting port 13 is approximately 500 mA.

The material of the water cooling pipe 18 is preferably a metal such as copper, which has good thermal conductivity. Further, when the water cooling pipe 18 is made of metal and is used also as a support, the cover 12 can be easily brought to the ground potential through the water cooling pipe 18.

The vapor deposition substrate C may be in the form of a rotating drum or a moving film, as well as a flat plate.

The case where the entire thin film of a-8i:H is manufactured has been described above, but in the present invention, the evaporation source l substance and the
;j j'i? By appropriately selecting a gas containing the five elements, the present invention can be applied to, for example, the production of thin films used in electrophotographic photoreceptors, display and writing TFTs, solar cells, image pickup devices, and the like. For example, gases containing modifying elements include hydrogen gas, oxygen gas, nitrogen gas,
Examples include halogen gas such as fluorine gas, ammonia gas, monosilane gas, phosphine gas, diborane gas, arsine gas, hydrocarbon gas such as methane gas, and freon gas. In addition to silicon, examples of evaporation source substances include carbon, germanium, tin, etc. By appropriately combining these modifying gases and evaporation source substances, amorphous silicon carbide, amorphous silicon nitride, amorphous silicon germanium , amorphous silicon tin, and amorphous germanium nanothin films can be produced.

As described above, the vapor deposition apparatus of the present invention includes a vapor deposition tank, a vapor deposition substrate and an evaporation source arranged in the vapor deposition tank, an inlet pipe for introducing a modification gas whose outlet is connected to the vapor deposition tank, and The electron beam generator includes a filament and an extraction electrode provided to surround the filament. and an electron beam exit opening provided in a part of the cup opposite to the filament, so that the filament material of the electron beam generator is not injected into the vapor deposition tank. Emission can be suppressed, and furthermore, filament contamination does not occur and early breakage of the filament can be prevented, and as a result, a deposited film without film contamination can be produced satisfactorily over a long period of time.

[Brief explanation of the drawing]

1M is an explanatory cross-sectional view showing one embodiment of the vapor deposition apparatus of the present invention, and FIGS. 2 and 3 are an explanatory vertical front view and an explanatory side view, respectively, showing an example of an electron beam generator. ■... Evaporation substrate 2... Evaporation source 3... Pelger 4... Heater 5... DC power supply
6...Introduction tube 10...Electron beam generator 11...Filament 12...Cover 13...Electron beam exit port 14...Insulating material 15...Frame 16...
・Lead rod 17...Filament heating power source 18...Water cooling pipe 21.22...Legs 2
3... DC power source 2nd circle ≠ Figure 3

Claims (1)

[Scope of Claims] 1) A vapor deposition tank, a vapor deposition substrate and an evaporation source disposed in the vapor deposition tank, an introduction pipe for introducing a modification gas whose outlet is connected to the vapor deposition tank, and the vapor deposition tank. The electron beam generator includes a single beam generator that irradiates a modifying gas introduced into a tank with an electron beam, and the electron beam generator includes a filament and a cover that is provided to surround the filament and that also serves as an extraction electrode. , and an electron beam exit opening provided in a portion of the cover facing the filament. 2) f? 2. The vapor deposition apparatus according to claim 1, wherein the electron beam emission direction of the electron beam generator is along the vapor deposition substrate.