| 摘要 |
PURPOSE:To have a high withstand voltage and prevent the damage of a substrate in manufacturing processes by possessing an element which is formed by forming an impurity region of the fixed conductivity type on a semiconductor substrate wherein a bevel surface composed of an inclined surface which makes the thickness gradually smaller from the peripheral edge part from the peripheral side surface. CONSTITUTION:Bevel surfaces 27 are formed on both surfaces front and back at an angle of inclination of 45 deg. from the peripheral edge part of the N type seniconductor substrate 20 composed of silicon to the peripheral side surface 26, and thus the outermost peripheral part is made to have the thickness of 200mum. Next, a P type impurity region 22 which surrounds an N type impurity region 21 inside in a buried state is formed by diffusing an impurity of P conductivity type. An emitter region 23 is formed by diffusing an N type impurity at a fixed diffusion depth on the side of the surface thereof. Thereafter, grooves 24 are formed at the depth reaching the N type impurity region 21, on the side of the surface of the P type impurity region 22, so as to surround the emitter region 23 by blade working, and grooves 25 are formed, at the depth reaching the N type impurity region 21, on the side of the back of the P type impurity region 22. |
