Patent ID: 8552474

Claim:
A junction field effect transistor structure, having a substrate connecting end, comprising: a substrate of a first conductivity type; a source electrode comprising a heavy-implanted well layer of a second conductivity type, a well layer of said second conductivity type provided within said heavy-implanted well layer of said second conductivity type, and an implanted layer of said second conductivity type provided on said well layer of said second conductivity type; a drain electrode having a same structure with said source electrode; a grid electrode comprising a first implanted layer of said first conductivity type provided within said heavy-implanted well layer of said second conductivity type, and a polysilicon layer provided above said first implanted layer of said first conductivity type; a buried layer of said first conductivity type provided on said substrate; a heavy-implanted well layer of said first conductivity type provided on said buried layer; a well layer of said first conductivity type provided within said heavy-implanted well layer of said first conductivity type; and a second implanted layer of said first conductivity type provided on said well layer of said first conductivity type, wherein the substrate connecting end is connected with said substrate by said buried layer of said first conductivity type, said heavy-implanted well layer of said first conductivity type, said well layer of said first conductivity type and said second implanted layer of said first conductivity type.