Patent ID: 6028346
Filing Date: 2000-02-22
Classification: H01L

Abstract:
A semiconductor device for supporting a plurality of mutually electrically isolated semiconductor elements, comprising:a semiconductor substrate of a first conductivity type having a major surface; andan isolation structure for electrically isolating semiconductor elements on said substrate from each other, the isolation structure including(a) a plurality of island regions for said semiconductor elements, separated by trenches formed on the major surface of said semiconductor substrate, each of said trenches including first and second substantially parallel opposed sidewalls and a bottom surface, said first opposed sidewall being of at least a given width within a common plane;(b) a first isolated oxide film formed on said first opposed sidewall and extending from said bottom surface of said trench to said major surface, said first isolated oxide film limited to less than the given width of said first opposed sidewall and spaced apart from said second opposed sidewall;(c) a second isolated oxide film formed on the bottom surface of said each trench and connected to said first isolated oxide film; and(d) a third isolated oxide film formed on the major surface of said semiconductor substrate and in contact said first isolated oxide film at the upper edge of said first sidewall of said trench.