Method for forming a lateral super-junction mosfet device and termination structure

A method for forming a lateral superjunction MOSFET device, comprising:

• providing a semiconductor body comprising a lateral superjunction structure including a plurality of alternating N-type and P-type thin semiconductor regions formed substantially in s parallel with a major surface of the semiconductor body, the alternating N-type and P-type thin semiconductor regions forming a drain drift region of the MOSFET device;
• forming a body region of a first conductivity type in a first surface of the semiconductor body and comprising a plurality of body region fingers arranged laterally on the first surface of the semiconductor body;
• forming a conductive gate on the semiconductor body at a near end of the lateral superjunction structure and being insulated from the semiconductor body by a gate dielectric layer, the conductive gate comprising a plurality of conductive gate fingers arranged laterally on the semiconductor body, each conductive gate fingers being adjacent to and overlapping a respective body region finger;
• forming a source region of a second conductivity type, opposite to the first conductivity type and comprising a plurality of source region fingers, each source region finger being formed in a body region finger and self-aligned with a first side of a conductive gate finger, each source region finger extending under the first side of the respective conductive gate finger to form a small overlap;
• forming a body contact region of the first conductivity type and comprising a plurality of body contact region fingers, each body contact region fingers being formed in a body region finger and adjacent to a source region finger formed therein;
• forming a drain region of the second conductivity type at a distant end of the lateral superjunction structure, the drain region extending through the lateral superjunction structure, the drain region comprising a plurality of drain region fingers;
• forming a plurality of transistor cells connected in parallel, each transistor cell comprising a conductive gate finger, a source region finger, a body contact region finger and a drain region finger arranged laterally within each transistor cell, each of the drain region fingers and the body contact region fingers comprises a heavily doped region finger having a termination region at an end of the heavily doped region finger;
• and
• forming a termination structure in the termination region of each heavily doped region finger, comprising forming one or more lightly doped termination columns having the same conductivity type as the heavily doped region finger and positioned near the end of the heavily doped region finger.