| 摘要 |
<p>PURPOSE:To realize the high speed of a solid-state relay and to simultaneously optimize the breakdown strength and the ON resistance of a MOS field-effect transistor as a switching element by a method wherein a photovoltaic diode part and a MOS field-effect transistor part are formed in single-crystal island regions whose depth is different from each other. CONSTITUTION:A single-crystal silicon region 3 which uses a polycrystalline silicon layer 1 as a support body and which has been insulated and isolated from the polycrystalline silicon layer 1 by a silicon oxide film 2 is provided. A photovoltaic diode part 5, a control circuit part 6 and a MOS field-effect transistor part 7 are formed respectively in the single-crystal silicon region 3 in a dielectric isolation substrate 4. In addition, individual elements are integrated, including 22 stages of the photovoltaic diode part 5, two thyristors and diodes as the control circuit 6 and two MOS field-effect transistors 7. The depth l1 of a single-crystal island of the photovoltaic transistor part 5 is set at 50mum; the MOS field-effect transistor part 7 is an element whose breakdown strength between a source and a drain is 250V; the depth l2 of a single crystal island is set at 30mum in order to optimize an ON resistance.</p> |
