Patent ID: 7799642

Claim:
A method for manufacturing a trench MOSFET semiconductor device, comprising the steps of: providing a heavily doped N+ silicon substrate; forming an N type epitaxial layer; forming a thick SiO2 layer; creating P body and source area formations by ion implantation without any masks; utilizing a first mask to define openings for a trench gate and a termination; thermally growing a gate oxide layer followed by formation of a thick poly-Silicon refill layer without a mask to define a gate bus area; forming sidewall spacers; forming P+ areas; removing said sidewall spacers; depositing tungsten to fill contacts and vias; depositing a first thin barrier metal layer; depositing a first thick metal layer; utilizing a second metal mask to open a gate bus area; forming second sidewall spacers; depositing a second thin barrier metal layer; depositing a second thick metal layer; and planarizing at least said second thick metal layer and said second thin metal layer to isolate the source metal portions from gate metal portions, whereby said trench MOSFET semiconductor device is manufactured utilizing only said first and said second masks.