| 摘要 |
PURPOSE:To increase the dv/dt without increasing the gate trigger current, by constituting the base region of the thyristor providing control electrode with the layers having higher and lower impurity concentration and by taking the thickness of 5 to 15 mum for the higher concentration layer. CONSTITUTION:The P type base layer 3 is placed on one surface of the N type base layer 4, the N type emitter region 5 is formed by diffusion, and the P type emitter layer 2 is formed on another surface of the layer 4. Next, the thyristor is constituted by locating the control electrode 11 on the region where the layer 3 is exposed, cathode 10 on the region 5, and anode 9 on the layer 2. With this constitution, the base layer 3 is constituted with higher and lower impurity concentration layers 31 and 32. To achieve this, first Ga is diffused by about 50 mum so that the surface concentration is 10<16> to 10<17> atoms/cm<3>, and also is diffused by about 25 mum on the surface region by taking the concentration as 10<18> to 10<19> atoms/cm<3>. After that, P is diffused by about 15 mum on the higher concentration layer, allowing to increase apparent resistor and improve dv/dt. |
