JPS6158967B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing an amorphous silicon semiconductor. Conventionally, amorphous silicon semiconductors have been manufactured by glow discharge decomposition method, ion sputtering method, etc., but these methods use silane gas, hydrogen gas, argon gas, etc. in a relatively vacuum of several Torr to 10 ^-2 Torr. Since plasma is used in a low-pressure atmosphere with low temperature, the amorphous silicon layer has the drawbacks of being contaminated with impurities, having poor film quality, nonuniform conductivity, and thermal instability. had. In view of the above-mentioned drawbacks, the present invention has been made to provide a method for manufacturing a semiconductor having a thermally stable amorphous silicon layer with good film quality, uniform conductivity, and the gist thereof is as follows: Silicon is heated and vaporized in a high vacuum evacuated to a pressure below ×10 ^-5 Torr, and then the vapor is ionized by colliding with accelerated electrons from an electron radiation source, and the ionized vapor particles are further accelerated in an electric field. kinetic energy of 1 to ¹⁰⁴ ev is applied to the base material, and 31 to 74 ev is applied to the normal to the base material.
The present invention resides in a semiconductor manufacturing method characterized in that an amorphous silicon layer is formed by colliding at an incident angle of .degree. DESCRIPTION OF THE PREFERRED EMBODIMENTS A method of manufacturing a semiconductor according to the present invention will be described below with reference to the drawings. FIG. 1 is a schematic diagram showing an example of an apparatus for carrying out the method of the present invention. In the figure, 1 is a vacuum chamber, and an exhaust port 2 is provided.
The exhaust port 2 is connected to an exhaust device (not shown) such as an oil rotary pump or an oil diffusion pump, and can exhaust the inside of the vacuum chamber 1 to a high vacuum of 5×10 ^-5 Torr or less. It is done like this. Vacuum chamber 1
Inside, a vapor deposition ion source 3 and an ion accelerating electrode 4 whose angle can be freely changed are installed. The evaporation ion source 3 includes a steam generation section 5 and a steam ionization section 6. The steam generating section 5 is composed of a crucible 7 for evaporating silicon, a 180° deflection E gun 8 for heating the crucible 7, and a water-cooled copper hearth 9 installed around the crucible 7 for cooling the crucible 7. has been done. The steam ionization section 6 is formed of a filament 10 for emitting thermionic electrons, a mesh electrode 11 for accelerating emitted electrons with an electric field, a guard 12 for controlling the electric field, and a baffle plate 13 for preventing scattering of silicon ions. There is. Further, 14, 15, and 16 are power sources for operating this device. Next, a method for manufacturing a semiconductor according to the present invention using the apparatus shown in FIG. 1 will be explained. First, the base material 18 is installed on the surface of the ion accelerating electrode 4, and 31 to 74 silicon ionized vapor particles are
The ion accelerating electrode 4 is fixed so that the collision occurs at an incident angle of .degree. Examples of the base material include polyvinyl chloride,
Polyvinyl fluoride, cellulose acetate, polyethylene terephthalate, polybutylene terephthalate, polyethylene, polypropylene, polycarbonate, polyimide, polyether sulfon,
Thin films of conductive materials such as aluminum and gold are formed on the surfaces of polymeric materials such as polyvarapanic acid, ceramic materials such as porcelain, ceramics, and glass, and crystal plates of inorganic compounds such as silica, alumina, and sodium chloride; Examples of conductive materials include aluminum, tantalum, iron, molybdenum, tungsten, nickel, gold, and silver. Next, silicon 17 is supplied to the crucible 7, and the exhaust port 2
The inside of the vacuum chamber 1 is evacuated to a high vacuum of 5×10 ^-5 Torr or less, the power supplies 14, 15, and 16 are turned on, and the 180° deflection E gun 8 is operated while cooling water is flowing through the water-cooled copper hearth 9. Heat silicon 17. Silicon-17 is vaporized at a vapor pressure depending on its heating temperature,
The vapor is diffused and reaches the vapor ionization section 6. In the steam ionization section 6, the filament 10 is heated with electricity by the power source 15 to emit thermoelectrons, a negative DC voltage is applied to the filament 10 and the guard 12 by the power source 16, and the mesh electrode 11 is grounded.
The thermoelectrons are accelerated in an electric field, collide with the vapor, and are ionized into a positively charged state to produce ionized vapor particles. Preferably, 0.5 to 50% of the silicon particles in the vapor are ionized to form ionized vapor particles. Next, a negative DC voltage is applied to the ion accelerating electrode 4 by the power source 14, and the ionized vapor particles are
A kinetic energy of 10 ⁴ eV is applied to cause the material to collide with the base material 5. At this time, if the base material 5 is placed so that the ionized vapor particles are incident at an angle of 31 to 74 degrees with respect to the normal to the base material 5, an amorphous layer is formed on the surface of the base material 5, and a semiconductor is manufactured. The kinetic energy is 10 ² to 10 ³ eV
It is preferable that In addition, a very small amount of hydrogen gas or fluorine gas may be introduced into the vacuum chamber to improve the conductivity of the amorphous silicon layer, and a very small amount of phosphine, diborane, etc. may be added to control valence electrons. Also good. Since the manufacturing method of the present invention is as described above, the amorphous silicon layer is uniformly laminated on the base material with almost no impurities, so that the conductivity is uniform and the layer is thermally stable. A semiconductor having an amorphous silicon layer can be easily manufactured. Next, the manufacturing method of the present invention will be explained using examples. Example In the apparatus shown in FIG. 1, 5 g of high-purity polycrystalline silicon ingots (silicon content 99.99%) were supplied to the crucible 7, and a glass plate was formed with a 500 Å thick gold film as the base material 18 by vacuum evaporation. The substrate was placed so as to be collided with the substrate at an incident angle of 50°, and vapor deposition was performed under the conditions shown in Table 1 to obtain a semiconductor having a 2 μm thick silicon amorphous layer on the substrate surface. Note that hydrogen gas was supplied from a hydrogen cylinder and maintained at the hydrogen gas partial pressure shown in Table 1 during production. The specific resistance of the obtained semiconductor was 3×10 ⁵ KΩcm, and the electron mobility was 0.02 cm ² /V·sec.
Next, the obtained semiconductor was heated at 200°C for 10 hours, but there was no change in resistivity or electron mobility. 【table】

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an example of an apparatus for carrying out the method of the present invention. DESCRIPTION OF SYMBOLS 1... Vacuum chamber, 2... Exhaust port, 3... Vapor deposition ion source, 4... Ion accelerating electrode, 5... Steam generation section, 6... Steam ionization section, 7... Crucible, 8...
...180° deflection E gun, 9...Water-cooled copper hearth, 10
...Thermionic emission filament, 11...Mesh electrode, 12...Card, 13...Baffle plate, 14,1
5, 16...Power supply, 17...Silicon, 18...Base material.

Claims (1)

[Scope of Claims] In a high vacuum evacuated to 15×10 ^-5 Torr or less, silicon is heated and vaporized, and then ionized by bombarding the vapor with accelerated electrons from an electron radiation source, Furthermore, the ionized vapor particles are accelerated in an electric field to impart kinetic energy of 1 to 10 ⁴ ev, and are caused to collide with the substrate at an incident angle of 31 to 74 degrees with respect to the normal to the substrate to form an amorphous silicon layer. A method for manufacturing a semiconductor, characterized by forming a semiconductor. 2. The manufacturing method according to claim 1, wherein the ionized vapor particles account for 0.5 to 50% of the vapor particles. 3. The manufacturing method according to claim 1 or 2, wherein the kinetic energy is 10 ² to ^{10 3} ev.