| 摘要 |
PURPOSE:To contrive the improvement of yield by a method wherein a semiconductor substrate is thinned after forming an active region at the surface side of the semiconductor substrate and after implanting a conductive-type impurity, heat treatment is applied. CONSTITUTION:An active region composed of a base region 2, an emitter region 3, a surface insulating oxide film and an electrode metal 5 is formed at the main surface side of a high-resistive semiconductor substrate 1. The semiconductor substrate is thinned from the rear side to form requested thickness and a high-impurity concentration layer 6 is formed by introducing the same conductive-type impurity 7 as the conductive type of the substrate by ion implantation. The layer 6 is irradiated by a laser beam to locally increase temperature at the layer 6 only and the impurity introduced by ion implantation is activated and good ohmic contact with an external electrode or a rear metal electrode is obtained. |
