FORMING SEMICONDUCTOR CELLS AND LAYERS BY RECRYSTALLISATION

摘要

A cell is formed on a silicon substrate 11 by depositing a silicon in a recess in the substrate, e.g. by plasma enhanced chemical vapour deposition, at a temperature below 550 DEG C. The alpha -silicon is recrystallised to a single crystal layer by heating the structure to a temperature between 550 and 900 DEG C. The technique overcomes the problems of wafer distortion experienced in conventional high temperature epitaxial growth. The cells may be used in mixed CMOS/bipolar integrated circuits. Alternatively a layer may be formed on a silicon substrate by depositing a layer of alpha -silicon on the substrate at a temperature below 550 DEG C and recrystallising by heating to a temperature of 530 to 900 DEG C.