Patent ID: 9508596
Filing Date: 2016-11-29
CPC Classification: H01L

Claim Text:
1. A process used in fabricating a metal-insulator-semiconductor field-effect transistor (MISFET), said process comprising: depositing a second oxide layer over a first region and a second region of a structure, said second region comprising a first oxide layer between said second oxide layer and an epitaxial layer, said first region having formed therein a first-type dopant source region, a second-type dopant body region, and a second-type dopant implant region, said first region corresponding to an active region of said MISFET and said second region corresponding to a termination region of said MISFET; forming a mask over said second region, said mask comprising a first plurality of mask elements separated by gaps, said mask further comprising a second plurality of mask elements over said first region, said mask elements in said second plurality separated by a gap; removing parts of said second oxide layer and said first oxide layer in said second region that are exposed through said gaps in said first plurality of mask elements, thereby exposing said epitaxial layer, and removing parts of said second oxide layer and said first-type dopant source region in said first region that are exposed through said gap in said second plurality of mask elements, thereby exposing said second-type dopant implant region; depositing second-type dopant into said epitaxial layer through openings formed in said second region by said removing parts of said second oxide layer and said first oxide layer in said second region, thereby forming field rings for said MISFET; forming a metal layer in contact with said first-type dopant source region and said second-type dopant implant region in said first region; and forming a passivation layer over said first and second regions, said passivation layer extending into said openings in said second region formed by said removing parts of said second oxide layer and said first oxide layer in said second region.