Toa Nenryo Kogyo, K. K.

Akihisa Matsuda

Mitsuo Matsumura

Hideo Yamamoto

Kazunobu Tanaka

Shigeru Iijima

A silicon thin film is composed of primarily silicon atoms, 0 to 8 atm % hydrogen, at least one element selected from the group including fluorine, chlorine, bromine and iodine, and an impurity element, wherein about 80 to 100% of microcrystalline grains are interspersed in an amorphous phase. The thin film is produced by deposition on a substrate in a plasma atmosphere using as a raw material gas silane (SiH.sub.4) or halogenated silane (SiH.sub.o--3 X.sub.4--1) wherein X represents a halogen or a combination of two or more halogens, and a dopant gas mixed with the raw material gas. The method comprises the steps of: (1) diluting the mixed gas with hydrogen in a ratio of the diluting gas to the raw material gas of from 50:1 to 100:1, to control the film deposition rate to produce a layer including mixed crystalline and amorphous substances; and (2) applying an electric power to provide a plasma discharge power density of from 0.1 to about 0.5 W/cm.sup.2, at a reaction pressure of 5 to 10 torr.

Growing community of inventors

Yatabe, Japan

Akihisa Matsuda