| 摘要 |
PROBLEM TO BE SOLVED: To provide a dielectric separation type semiconductor device which, even when a high breakdown voltage is set or a multiplicity of high breakdown voltage semiconductor elements are integrated, can suppress increase in its chip area. SOLUTION: A diffusion region 13 of a first conduction type of an active layer 12, electrically connected to one electrode 16 (or K), has a first part opposed to a diffusion region 14 of a second conduction type electrically connected to the other electrode 17 (or A) of the active layer, and also has a second part opposite to an element isolation region formed in a trench 20. An element region surrounded by this element isolation region includes a first region A1 between the above first part and the diffusion region 14 of the second conduction type, electrically connected with the electrode 16, and also includes a second region A2 between the above second part and the element isolation region 20. And a potential of the diffusion region of the second conduction type connected with the electrode 16 of the element region within the trench is set to be equal to or nearly the same as a potential of a region B outside of the trench and opposite to the diffusion region of the second conduction type. |
