Patent ID: 8030714

Claim:
A coaxial P-channel metal-oxide-semiconductor field-effect transistor structure, which is a coaxial enhancement mode or depletion mode transistor structure formed on an N-type substrate or an N-type well, comprising: an annular P-type doped semiconductor drain area; an annular P-type doped semiconductor source area; an annular channel area formed on said N-type substrate or said N-type well and arranged between said annular semiconductor drain area and said annular semiconductor source area; an annular polysilicon or conductor gate arranged over said annular channel area and insulated by an oxide layer; a body connected to said annular semiconductor source area and using said N-type substrate or said N-type well as a reference potential; an external coaxial annular power supply conductor layer connected to said body and said annular semiconductor source area; an inner axial conductor connected to said annular semiconductor drain area where carriers concentrate; and wherein said annular elements and said annular electrodes are fabricated into a coaxial structure, and the annular P-type doped semiconductor drain area is laterally formed in contact with the inner axial conductor.