Patent ID: 6693325
Filing Date: 2004-02-17
Classification: H01L

Abstract:
A semiconductor device having a SOI structure comprising:a semiconductor substrate of a first conductivity type; a surface silicon layer formed over an insulating layer on the semiconductor substrate; a trench formed by etching a predetermined portion of the surface silicon layer, the insulating layer and a part of the semiconductor substrate to be used for an element separating region; a STI oxide layer formed in the trench; a transistor surrounded by the STI oxide layer with a gate electrode formed on the surface silicon layer and a source/drain region formed in the surface silicon layer of both edges of the gate electrode such that a bottom part of the source/drain region is in contact with the insulating layer; a first groove formed between the STI oxide layers at one side of the transistor by etching the surface silicon layer and the insulating layer to expose a predetermined portion of a first active region, said first active region being formed in a second-conductivity-type well in the semiconductor substrate; a first diode diffusion region of the first conductivity type formed in the second-conductivity-type well under the first groove; a second groove formed between the STI oxide layers at one side of the first groove by etching the surface silicon layer and insulating layer to expose a predetermined portion of a second active region, said second active region being formed in the first-conductivity-type well in the semiconductor substrate; and a second diode diffusion region of the second conductivity type formed in the second-conductivity-type well under the second groove.