Patent ID: 8878292

Claim:
An accumulation mode field effect transistor (AccuFET) comprising: trenched gates disposed in trenches opened in a top epitaxial layer on top of a bottom epitaxial layer both are doped with a first conductivity type wherein the top epitaxial layer having a higher dopant concentration and encompassing a source region near a top surface of a semiconductor substrate surrounding said trenched gates wherein each trenched gate is padded by a gate oxide layer and surrounded completely by regions of said first conductivity type including said source region and said top epitaxial layer of said first conductivity type and wherein said trenched gate includes a gate material of a second conductivity type filling the trenches and supporting a stick-up gate segment with the gate material extended above a top surface of said semiconductor substrate and the stick-up segment is surrounded by sidewall spacers disposed above the source region; and slots opened in the top epitaxial layer between the sidewall spacers and parallel to and disposed at a distance away from said trenched gates wherein said slots extended into said top epitaxial layer of the first conductivity type and completely filled with the gate material doped with said second conductivity type and surrounded directly by said top epitaxial layer of said first conductivity type wherein said slots filled with said gate material contacting the source region laterally extended underneath the sidewall spacers from sidewalls of the trenched gates to the slots.