Insulated gate field effect semiconductor device

摘要

A high quality semiconductor device comprising at least a semiconductor film having a microcrystal structure is disclosed, wherein said semiconductor film has a lattice distortion therein and comprises crystal grains at an average diameter of 30 ANGSTROM to 4 mu m as viewed from the upper surface of said semiconductor film and contains oxygen impurity and concentration of said oxygen impurity is not higher than 7x1019 atomsxcm-3 at an inside position of said semiconductor film. Also is disclosed a method for fabricating semiconductor devices mentioned hereinbefore, which comprises depositing an amorphous semiconductor film containing oxygen impurity at a concentration not higher than 7x1019 atomsxcm-3 by sputtering from a semiconductor target containing oxygen impurity at a concentration not higher than 5x1018 atomsxcm-3 in an atmosphere comprising hydrogen at not less than 10% in terms of partial pressure; and crystallizing said amorphous semiconductor film at a temperature of from 450 DEG C. to 700 DEG C.