Motorola Corporation

Phillip H Williams

Bridgette A Bergami

Clifford I Drowley

Marco Racanelli

A semiconductor wafer (11) with a lattice mismatched film (12) on its upper surface is placed on a flat support surface (15). A laser beam (13, 23, 24, 26, 27) is directed onto the film (12). Curvature of the semiconductor wafer caused by the film (12) is measured simultaneously with film thickness based on characteristics of the reflected laser beam (23, 24, 26, 27). Strain within the film (12) is calculated from the curvature of the semiconductor wafer, film composition is calculated from the stress and thickness based on known properties of the film (12).

Simultaneously measuring thickness and composition of a film

Dielectric filled isolation walls for semiconductor devices and integrated circuits of improved characteristics and ease of manufacture are formed by etching trenches in a semiconductor substrate and refilling the trenches with multiple layers of silicon oxy-nitride. Alternative oxygen rich and nitrogen rich oxy-nitride layers are used. For the narrowest trenches two layers suffice. Where trenches of different widths are present the wider trenches receive multiple layer pairs. A cap layer of oxy-nitride is added to insure filling of any trench intersections. The oxy-nitride desirably has a composition Si.sub.x O.sub.y N.sub.z where x, y, and z are in the range 0.25-0.4, 0.27-0.6, and 0.0-0.35, respectively, for the oxygen rich material and where x, y, and z are in the range 0.34-0.43 m 0.0-0.35, and 0.28-0.6, respectively, for the nitrogen rich material, expressed in atomic fraction and x+y+z=1. Both compositions of oxy-nitride are formed in the same LPCVD reactor by changing the conditions during layer deposition.

Multilayer trench isolation process and structure

Dielectric filled isolation walls for semiconductor devices and integrated circuits of improved characteristics and ease of manufacture are formed by etching trenches in a semiconductor substrate and refilling the trenches with multiple layers of silicon oxy-nitride. Alternative oxygen rich and nitrogen rich oxy-nitride layers are used. For the narrowest trenches two layers suffice. Where trenches of different widths are present the wider trenches receive multiple layer pairs. A cap layer of oxy-nitride is added to insure filling of any trench intersections. The oxy-nitride desirably has a composition Si.sub.x O.sub.y N.sub.z where x, y, and z are in the range of 0.25-0.4, 0.27-0.6, and 0.0-0.35, respectively, for the oxygen rich material and where x, y, and z are in the range 0.35-0.43m 0.0-0.35, and 0.28-0.6, respectively, for the nitrogen rich material, expressed in atomic fraction and x+y+z=1. Both compositions of oxy-nitride are formed in the same LPCVD reactor by changing the conditions during layer deposition.

Growing community of inventors

Mesa, AZ, United States of America

Phillip H Williams