Inventors:
Martin E. Garnett - Los Gatos CA
Michael R. Hsing - San Jose CA
Assignee:
Micrel, Inc. - San Jose CA
International Classification:
H01L 21265
Abstract:
A method in accordance with one embodiment of the present invention may be used to self-align isolation regions, sinkers, and wells. In this improved method, P+ isolation regions, N+ sinkers, and P-wells are defined using the same masking step used to define the N-wells. The use of a single masking step to initially define the P+ isolation regions, N+ sinkers, N-wells, and P-wells results in the self-alignment of these regions. Several critical mask alignments are thereby eliminated, thus avoiding/simplifying fabrication steps, conserving die area, and allowing increased component density.