Gettering of impurities

Abstract

Abstract PURPOSE:To make defects to be generated in the whole region of the pattern adhering part, and to control quantitatively distribution inside of the surface of the defects having ability to absorb impurities by a method wherein a thin film having the edges is provided on the back of a semiconductor substrate, and the heat treatment is performed at the prescribed temperature. CONSTITUTION:An Si3N4 film or a polycrystalline Si thin film, etc., having internal stress is adhered on the back of the semiconductor substrate 2 of Si, GaAs, InSb, etc., according to the means of evaporation, etc. Then the film is made to be survived locally according to the photo etching method to form the thin film 1 having the edges. At this constitution, stress to be applied to the substrate 2 is decided as follows. Namely, when the substrate is the Si substrate, because yield stress to be generated when the heat treatment at 1,000 deg.C is performed to the substrate thereof is 7X10<5> dyne/cm<2>, the value obtained by dividing the product of internal stress of the thin film and thickness of the film by pattern breadth is specified to 2.8X10<5> dyne/cm<2> or more. Accordingly distribution inside of the surface of the defects to act as to absorb impurities is controlled quantitatively.

Inventors

• 👤 Yoichi Mada
• 👤 間田　洋一

Bibliographic Details