Manufacture of semiconductor device

Abstract

Abstract PURPOSE:To prevent the formation of a bird beak at the end edge of an SiO2 layer, and to improve the degree of integration of an IC by previously shaping an Si3N4 layer, through which oxygen molecules are not permeated, thinly and deeply at a position partitioning an active region and an isolation region. CONSTITUTION:An SiO2 layer 17 is shaped onto the surface of an silicon substrate 11, and thin deep trenches 18 are formed through etching at the positions of the borderlines of an active region 15 and an isolation region B through the exposure of X-rays or electron beams. An Si3N4 film 14 is shaped onto the whole surface so as to bury the trenches 18, and the SiO2 layer 17 exposed in the isolation region B is grown through whole-surface oxidation. An Si3N4 layer 16 on an active region A is removed through etching, and a device layer 12 is formed in the active region A. Consequently, the Si3N4 layer 16 prevents permeation through the active region A side of oxygen molecules when the thick SiO2 layer 17 is shaped in the isolation region B. Accordingly, the end edge of the thick SiO2 layer 17 in the isolation region B is formed along the Si3N4 layer, thus removing a bird beak.

Inventors

• 👤 Masanori Ishimaru
• 👤 石丸　正規

Bibliographic Details