JPH0360019A - Manufacture of polycrystalline silicon film - Google Patents

Abstract

PURPOSE:To obtain a polycrystalline silicon film with excellent work efficiency by annealing amorphous silicon with laser beam simultaneously with precipitation of the amorphous silicon. CONSTITUTION:A substrate 2 is put in a reactor filled with silane gas, and a laser beam 4 for CVD from a light source 4 is applied onto the surface of the substrate 2 through a window 5 provided at the reactor 1. On the other hand, laser beam for annealing from a light source 6 is also applied onto the surface of the substrate 2 through a window 4 provided at the reactor 1. As the light source 3 for laser CVD, high power ultraviolet rays are used, which can precipitate amorphous silicon on the surface of the substrate 2 by decomposing the silane gas in the reactor 1. Hereby, precipitation of amorphous silicon and annealing of the precipitated amorphous silicon are done simultaneously, and a polycrystalline silicon film is grown on the surface of the substrate 1.

Description

[Detailed description of the invention] (B) Industrial application fields The present invention is based on polycrystalline silicon 1 model 58! Concerning how to crawl.

(b) Conventional technology Plasma CVD is a film-forming technology that can be applied to the surface of a substrate to meet the demands for low-temperature film formation and large-area film formation.
A non-single-crystalline film such as an amorphous film or a polycrystalline film is obtained by a method such as a method, a thermal CVD method, a J'4 full-4 vacuum evaporation method, or a sputtering method. convert it into a crystal film,
Another method is to convert a polycrystalline film into a single crystalline film. As an example, for example, JP-A-63-170976
The prior art disclosed in the publication includes a method of forming an amorphous film on the surface of a substrate at a low temperature in advance by plasma CVD, and then annealing by laser beam irradiation to obtain a polycrystalline film.

(c) Problems to be solved by the invention However, since the intensity distribution of the laser beam used for annealing generally exhibits a Gaussian distribution with a peak at the center, it is necessary to perform uniform annealing at the center and peripheral portions of the laser beam. Furthermore, since the crystal grain size of the polycrystalline film is determined by the annealing time and temperature, there was a problem in terms of reproducibility.

(2) The T-crossing invention for solving the problem was made in view of this problem. A decomposable energy beam is injected into the vicinity of the substrate surface to precipitate amorphous silicon on the substrate surface, and at the same time, the amorphous silicon is annealed with a laser beam to obtain a polycrystalline silicon film.

(E) Function According to the present invention, since the amorphous silicon is annealed with a laser beam at the same time as the amorphous silicon is deposited, a polycrystalline silicon film can be obtained with good workability.

(f) Example FIG. 1 is a conceptual diagram showing the configuration for carrying out the method of the present invention, where l is 5i11. ．． 5i-Hs, or 5
id1. Silane gas such as 0.1 to 10 Torr
The reactor is filled with a certain amount of pressure, and insulator plates 2 made of an insulating material such as glass or ceramic are placed in the reactor. 3
1 is a laser CVD light source, and CVD laser light 4 from the light source 3 is irradiated onto the surface of the substrate 2 through a window 5 provided in the reactor 1. Reference numeral 6 denotes a laser annealing light source, and the annealing laser beam 7 from the light source 6 is also transmitted through a window 4 provided in the reactor I.
The light source 3 for laser CVD uses 0, 01, which can decompose the silane gas in the reactor 1 and deposit amorphous silicon on the surface of the substrate 2. A high-power ultraviolet light such as an excimer laser or the second harmonic of an Ar laser with an output of about IOJ/cm" is used. Also, a light source 6 for laser annealing is used.
As such, it is suitable for heat-treating amorphous silicon deposited on the surface of the substrate 2 to polycrystallize it. Ar laser, excimer laser, YAG laser, SHG laser, alexandrite laser, etc. are used, and their output is 0.
1 to 100 J/ca". In such a configuration, at the same time as the laser CVD light source 3 is excited, the laser annealing light source 6 is also excited, and the amorphous silicon is deposited by the laser CVD and the precipitated amorphous silicon is annealed. A polycrystalline silicon film having a thickness of 0.1 to jp11 is grown on the surface of the substrate 1 by simultaneously carrying out the treatment for 0.1 to 1 minute and 1 m. Fig. 2 shows another configuration for carrying out the method of the present invention. The major difference from the method shown in FIG. 1 is that a single laser light source is used as a light source for laser CVD and a light source for laser annealing.

That is, the laser beam 11 from the laser light source 10 is a half mirror.
The annealing laser beam 13 branched at I2 and reflected by the mirror 12 is directly irradiated onto the surface of the substrate 2 in the reactor 1, and the laser CVD laser beam 14 that has passed through the half mirror 12 is directed to the reactor 1. Near the surface of the substrate 2 placed inside (
It becomes l1lI which is irradiated to fi. Such HIj
In r&, the power of the CVD laser beam 14 is required to be about 0.01-10 J/ctx', and the annealing laser beam 13 requires a power of 0.1-100 J/cm''. The reflectance of the half mirror 12 needs to be within the range of 10% to 90%.

(G) Effects of the Invention As is clear from the above description, the present invention allows a silane-based reactive gas to be suspended near the surface of the plate, and an energy beam capable of decomposing the reactive gas is applied to the plate surface. At the same time, amorphous silicon is deposited on the plate surface and the amorphous silicon is annealed with a laser beam to obtain a polycrystalline silicon film. A crystalline silicon film can be formed with good reproducibility.

[Brief explanation of drawings]

FIG. 1 and FIG. 2 are conceptual diagrams showing the configuration when implementing the method of the present invention, respectively. DESCRIPTION OF SYMBOLS 1... Reaction furnace, 2... Substrate, 3... Laser CVD light source, 4.14... CVD laser light, 6... Light source for laser annealing, 7.13... Laser light for annealing, 10...Laser light source, 12...Half mirror - Sanyo Denkirin Company

Claims (1)

[Claims] (1) When growing a polycrystalline silicon film on the surface of a substrate, with a silane-based reactive gas floating near the substrate surface, an energy beam capable of decomposing the reactive gas is irradiated near the substrate surface. A method for producing a polycrystalline silicon film characterized by depositing amorphous silicon on a surface and simultaneously subjecting the amorphous silicon to annealing treatment using a laser beam.