JPS58115020A - Preparation of amorphous silicon film - Google Patents

Abstract

PURPOSE:To prepare the titled film for electron devices capable of controlling various characteristics widely, by introducing SiH4 and B(CH3)3 gas into a vacuum reaction vessel, and forming an amorphous silicon carbide semiconductor layer containing B on a substrate. CONSTITUTION:In forming an amorphous Si(a-Si) film from SiH4 by the well- known glow discharge method, B(CH3)3 vapor is introduced into a vacuum reaction vessel for introducing SiH4 thereinto. SiH4 and B(CH3)3 are decomposed and reacted by the glow discharge method to produce the aimed amorphous silicon carbide, containing B, stabilized with H, and expressed by the formula. The resultant film has a two-component composition as compared with an (a-Si: H) film, and the physical properties, e.g. electrical and optical properties, can be changed depending on the ratio of the composition contained therein.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing amorphous silico/membrane,
In particular, the present invention relates to a method of manufacturing an amorphous silicon carbide film for constructing an electronic device having an active function, a nonlinear function, a conversion function, or the like.

In recent years, amorphous semiconductors have attracted attention as new electronic materials. Since amorphous semiconductors lack long-range order in their atomic arrangement, various physical properties such as electrical properties, optical properties, and material constants can be continuously controlled by the composition of the component elements that become amorphous. There are advantages. In addition, because the atomic arrangement is amorphous, there is no inherent anisotropy in properties due to crystal planes or axial directions like in single crystals.
Unlike single crystals, it does not have a uniform melting point and has a softening temperature range [2, exhibits thermoplasticity. Therefore, thin films made by not only mechanical processes such as rolling and compression molding but also vapor deposition and sputtering have excellent workability, and can be mass-produced with relatively simple equipment and energy savings, compared to single crystal semiconductors. Therefore, it can be used as an inexpensive material for electronic devices.

In addition, amorphous semiconductors obtained by conventional manufacturing methods are
Although there were problems such as the existence of high-density localized levels and the difficulty of controlling nine valence electrons, the recently developed monoion gas (S i
The hydrogenated amorphous silicon film (hereinafter abbreviated as a-8i) obtained by decomposing H4) by glow discharge does not have such problems and can now be made to have structural sensitivity. Therefore, attempts have been made to utilize the hydrogenated a-F) i as a material for electronic devices such as electrophotographic photoreceptors, solar cells, and optical sensors.

However, the above a-5i has a single composition of silicon, although hydrogen is included for stabilization. Therefore, there are limitations in physical properties such as electrical and optical properties, which narrows the range of application and also limits doping methods.

The present invention has been made in view of the above-mentioned drawbacks of conventional amorphous semiconductors for electronic devices, and provides a method for manufacturing an amorphous silicon carbide film for electronic devices that facilitates control of valence electrons and has a wide range of applicability. be. The present invention will be explained in detail below.

A feature of the present invention is that the a-5i film is formed by a conventionally known glow discharge method using monosilane gas S I H4, and at that time, trimethylbromine B(CH3)3 is added to the reaction chamber into which monosilane gas S iH4 is introduced. The point is to introduce steam. S s H, s and B led into the same reaction chamber
(CH3)3 is decomposed and reacted by glow discharge method to a-
Amorphous silicon carbide represented by 5'xC1-x:H is produced. Obtained a-5txC,:
Since the H film has a binary composition compared to the a-8t:H film, physical properties such as electrical and optical properties can be changed by changing the proportion of the contained composition, and it can be used for electronic devices. It can be adjusted according to the required functions. A5txC+, which was generated by using B(CH3)3 when incorporating the above carbide,
:B is added into the H film at the same time. The P-type groove conductivity can be controlled by the amount of B added.

fC,a-S iXC11 obtained by the above production method:
Since the H film allows control of valence electrons, a PN junction can be formed by selecting the type and concentration of impurities introduced. Therefore, it is possible to configure an active element that can perform an amplification function in the same way as a conventional transistor (transistor), and it can also be used as an element that can perform non-linear functions that appear in current-voltage, such as a diode, and even as an element that can perform optical energy. The following table shows the preferable value of X when used in each electronic device, which can be used as an electronic device material for producing an element having a conversion function such as a solar cell that converts into electrical energy.

It should be noted that the amorphous silicon carbide film having the above composition is supplied for electronic devices after being doped with an impurity for converting it to P or N type, if necessary.

Next, specific examples of the present invention will be described using a photoconductive cell as an electronic device.

Inside the vacuum-maintained reaction chamber of the dielectric glow discharge device,
A glass substrate 1 on which a transparent conductive film 2 has been previously deposited as shown in the figure is installed and maintained at a temperature of 200° C. by heating with a heater. Next, a mixed gas containing 10% monosilane in hydrogen and 8% hydrogen gas containing trimethylbromine vapor saturated at room temperature was introduced into the reaction tank. . A high frequency of 18.56 MHz 200 W is applied to the induction coil of the reaction tank into which the mixed gas has been introduced to cause a glow discharge, and a-5iC containing boron is placed on a glass substrate coated with a transparent conductive film:
H film 3 is formed, and A4 electrodes 4 are formed on the a-5iXC, c:H1-X film 8 in a desired pattern as necessary to form a photoconductive cell with a sandwich structure as shown in the figure. Created.

The photoconductive property exhibited by the photoconductive cell having the above structure is that the conductivity in the dark state is ~1O-10(Ω・(1)), and is ~10'( for an incident light intensity of 0.1 mW/-II! Ω@cIn
)' is.

It also exhibited photoconductive properties with a sensitivity peak around a wavelength of 580 nm. Such characteristics can be used as a contact type one-dimensional optical sensor array used in a facsimile reader.

In the above manufacturing process, the conductivity in the dark can be lowered by increasing the amount of trimethylbromine doped, and a product with such characteristics can be used as a sensor for an image pickup tube.

As described above, according to the present invention, in the process of forming an amorphous silicon film using the glow discharge method, by mixing trimethylbromine gas into monosilane gas and growing it,
Compared to amorphous films made of a single silicon composition, it is easier to control physical properties, and physical properties can be controlled over a wide range, and active functions, nonlinear functions, conversion functions, etc. are required. 0 that can be used as a material for electronic devices

[Brief explanation of drawings]

The figure is a sectional view of an embodiment according to the present invention. 1. Glass substrate 2: Transparent electrode 3: a-3iXC1,:H4: Az electrode Agent Patent Attorney Aihiko Fuku

Claims (1)

[Claims] 1. In a method for manufacturing an amorphous silicon film for electronic devices formed by laminating it on a substrate, monosilane gas and hydromethylbromine (B(CH8
) 3) Introducing gas and depositing boron on the substrate by glow discharge L fca S 1xC11:
1. A method for producing an amorphous silicon film, comprising forming an amorphous silicon carbide semiconductor layer described by H.