| 摘要 |
PROBLEM TO BE SOLVED: To provide a surge protecting semiconductor device which has a low capacitance and a high surge resistance. SOLUTION: In the surge protecting semiconductor device, a side surface and bottom surface of a p-type epitaxial layer 3 of a low concentration are closed with an n-type semiconductor layer 4 and n-type semiconductor substrate 1, and a p-type semiconductor layer 2 is included which extends from the surface of the p-type semiconductor device into its layer. When applying a reverse bias between the p-type semiconductor layer 2 and the n-type semiconductor substrate 1, a depletion layer produced in the p-type epitaxial layer 3 of a low concentration becomes like a continuous bowl along the side surface to bottom surface of the epitaxial layer 3, and since the p-type epitaxial layer 3 is of a low concentration, the depletion layer can occupy a large area and then becomes a low capacitance. Further, increasing a reverse bias allows the depletion layer to reach the bottom surface of the p-type semiconductor layer 2 to be a punch-through, and a non-concentrative, a loose distribution of a current can be obtained just below the p-type semiconductor layer 2, thereby forming the surge protecting semiconductor device having a high surge resistance. COPYRIGHT: (C)2006,JPO&NCIPI
|
