| 摘要 |
PURPOSE:To improve electric characteristics by restraining the expansion of depletion layers and then blocking the characteristic deterioration due to the impression of reverse withstand voltage by a method wherein a bevel surface formed to alleviate field concentration is formed by two step inclined surfaces. CONSTITUTION:P type base layers 21 and 22 are formed on the front and back surfaces of an N type base layer 20. An N<+> type cathode layer 23 is formed in the upper layer 21. An anode electrode 24 is formed on the surface of the lower layer 22. A gate electrode 25 is formed on the main surface of the layer 21. A cathode electrode 26 is so formed on the main surfaces of the layers 21 and 23 as to extend over these main surfaces. Here, the bevel surfaces 27 to prevent the field concentration at the interface of P-N junction formed between both layers 20 and 21, 22 are formed on the peripheral surfaces of these layers by two step inclined surfaces. Then, a glass protection film 28 is formed on the surface 27. |
