Patent ID: 7612431
Filing Date: 2009-11-03
Classification: H01L

Abstract:
1. A trench polysilicon diode comprising electrostatic discharge (ESD) protection comprising: a N+ (P+) type substrate; a N− (P−) type epitaxial region over said substrate; a trench formed in said N− (P−) type epitaxial region, said trench comprising a top surface; an insulating layer lining said trench; a polysilicon filling said trench forming a top surface of said trench; a P+ (N+) type doping polysilicon in said trench and formed by a P+ (N+) type ESD implant; a N+ (P+) type doping polysilicon in said trench and formed by a N+ (P+) type source implant; and a diode formed in said trench such that a portion of said diode is formed below said top surface of said trench, wherein said trench comprises an ESD trench.