Method for fabricating semiconductor photodetector

A process for producing a photodetector comprising a vertical static induction transistor, comprising the steps of:

• forming a control gate region on a first principal surface of a silicon wafer;
• forming a shielding gate region on said first principal surface surrounding said control gate region;
• forming at least one first principal electrode region formed on said first principal surface in an area between said control region and said shielding gate region;
• forming a second principal electrode region on a second principal surface of said silicon wafer on the side opposite said first principal electrode region, wherein said step of forming said at least one first principal electrode region on said first principal surface comprises forming a top surface of said region flush with said first principal surface, etching a notch in said first principal surface, said shielding gate region being formed at an apex of said notch, and forming an oxide film by oxidizing an upper part of said shielding gate region, and wherein remaining portions of said shielding gate region are deeper in said silicon wafer than said first principal electrode region.