| 摘要 |
PURPOSE:To obtain a stable operation, in a rectifying diode having a p<+>n or p<+>n<+> contact structure, by differentiating the area ratio between an n layer or n<+> layer and a p<+> layer in a chip, selecting the ratio lower at the central part of the chip, where the current concentration is easily formed by heating, than the ratio at the peripheral part, thereby equalizing the heating distribution. CONSTITUTION:On an n<+> type Si substrate 1, a p type layer 2 is epitaxially grown, and a plurality of independently neighboring p<+> type layers 3 and n type layers 4 are diffused and formed. Then an Al electrode 6 is provided on the surfaces of said regions. A solder electrode 5 is deposited on the back surface of the substrate 1. In this constitution, the area ration An/Ap between the n type layer and the p<+> layer 3 is differentiated depending on the positions of the chip. Namely, when the width of the layer 4 at the central part is 5mum, the width at the peripheral part is 10mum, and the width is gradually widened. The ratio An/ Ap at the central part is 1, whereas the ratio at the peripheral part is 2. In this way, the current concentration in the electrode contact region becomes gentle, and the stable operation can be performed even at a high temperature. |
