Patent ID: 6046470
Filing Date: 2000-04-04
Classification: H01L

Abstract:
A trenched gate MOSFET comprising:a semiconductor body comprising a drain region of a first conductivity type;a trench formed in a surface of said semiconductor body;a gate formed in said trench, said trench being lined with a dielectric layer for electrically insulating said gate from said semiconductor body;a body region of a second conductivity type located adjacent said trench;a source region of said first conductivity type located adjacent said trench and abutting said surface of said semiconductor body;said MOSFET comprising a temperature detection cell, said temperature detection cell comprising a first diffusion of said first conductivity type and a second diffusion of said second conductivity type, said second diffusion enclosing and forming a PN junction with said first diffusion, said second diffusion extending to a level below a level of a bottom of said trench and having a dopant concentration such that said second diffusion functions to protect said dielectric layer at a comer of said trench from damage from high electric fields and to inhibit a turn-on of a bipolar transistor comprising said first and second diffusions, said PN junction forming a temperature detection diode.