Patent ID: 8072013

Claim:
A semiconductor structure comprising: a trench polysilicon diode for electrostatic discharge protection, said trench polysilicon diode comprising: a N+ (P+) type substrate; a Nâˆ’ (Pâˆ’) type epitaxial region over said substrate; a trench formed in said Nâˆ’ (Pâˆ’) type epitaxial region, said trench comprising a top surface; an insulating layer lining said trench; a polysilicon filling said trench forming said top surface of said trench; a P+ (N+) type doping polysilicon in said trench and formed by a P+ (N+) type electrostatic discharge (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.