Method of producing a schottky varicap

摘要

A method of producing a Schottky varicap (25) including: (a) providing an epitaxial layer (12) on a semiconductor substrate (1); (b) providing an insulating layer including an oxide layer and a nitride layer on a predetermined area of the surface of the epitaxial layer (12); (c) depositing a polysilicon layer (6); (d) applying a first high temperature step to diffuse a guard ring (10) around the first predetermined area; (e) removing a predetermined portion of the polysilicon layer (6) to expose the first silicon nitride film (5); (f) implanting atoms through at least the first oxide film (4) to provide a predetermined varicap doping profile; (g) applying a second high temperature step to anneal and activate the varicap doping profile; (h) removing the first oxide film (4) to provide an exposed area; (i) providing a Schottky electrode (17) on the exposed area.