IGBT SEMICONDUCTOR DEVICE

摘要

To provide a semiconductor device in which dielectric breakdown strength in a peripheral region is increased without increasing on-resistance. An IGBT comprises a body region, guard ring, and collector layer. The body region is formed within an active region in a surface layer of a drift layer. The guard ring is formed within a peripheral region in the surface layer of the drift layer, and surrounds the body region. The collector layer is formed at a back surface side of the drift layer, and is formed across the active region and the peripheral region. A distance F between a back surface of the guard ring and the back surface of the drift layer is greater than a distance between a back surface of the body region and the back surface of the drift layer. A thickness H of the collector layer in the peripheral region is smaller than a thickness D of the collector layer in the active region. According to this type of configuration, fewer carriers are injected into the thicker semiconductor layer in the peripheral region than in the active region. Consequently, in this IGBT, the density of carriers injected into the peripheral region can be made smaller than that of the active region. Thus, in this IGBT, the dielectric breakdown strength in the peripheral region can be improved without increasing the on-resistance in the active region.