| 摘要 |
<p>Provided is a semiconductor device wherein a peripheral region is permitted to have a high withstand voltage without increasing on-resistance. An IGBT is provided with a body region, a guard ring and a collector layer. The body region is formed on the front layer of a drift layer in an active region. The guard ring is formed on the front layer of the drift layer in the peripheral region so as to surround a body region. The collector layer is formed on the rear surface side of the drift layer and is formed over the active region and the peripheral region. The distance (F) between the rear surface of the guard ring and the rear surface of the drift layer is longer than the distance between the rear surface of the body region and the rear surface of the drift layer.The thickness (H) of the collector layer in the peripheral region is less than the thickness (D) of the collector layer in the active region. In the peripheral region, less carriers are injected into the thick semiconductor layer compared with the active region. Therefore, in the IGBT, density of the carriers injected into the peripheral region is lower than that of the active region. Namely, in the IGBT, the withstand voltage in the peripheral region is improved without increasing the on-resistance in the active region.</p> |
