| 摘要 |
PURPOSE:To increase phototrigger sensitivity and to shorten turn on time by improviding the shape of the concave section at a light incident part. CONSTITUTION:A thyristor consisting of a P type emitter layer 1, an N type base layer 2, a P type base layer 3, N type emitter layer 4, an anode electrode 5, and cathode electrodes 6 is formed. Wherein, J1, J2 and J3 are junction parts respectively and a depletion layer 7 which effectively work as a light-sensitive layer for trigger light 9 is formed at the J2 section. A concave section 8a effectively feeding the light into the depletion layer 7 is shaped so that the side wall surface of the concave section 8a may have an easy slope and the concave section 8a is formed to reach the N type base layer 2 by crossing over the vicinity of the junction J2 or the junction J2. Furthermore, P<+> type layers 10 are provided at the exposed main surface section 10 of the P type base layer 3. In this way, phototrigger sensitivity improves and free carriers quickly move by the electric field around the side wall of the concave section. |
