| 摘要 |
PURPOSE:To facilitate manufacture and to improve yield by providing a silicon layer on a sapphire insulating substrate. CONSTITUTION:At one end on a thin and long sapphire substrate 1, a semiconductor silicon area for constitution part of a sensor covered with an ion sensitive film 9 is formed. From this area 2, a drain area 4, a source area 3, and an earth area the extended to the other end of the substrate 1; the drain area 4 is connected to a drain electrode, and the source area 3 and earth area 5 are short- circuited by a source electrode. Consequently, the reverse surface of the silicon layer is insulated already in the stage of a wafer, and the silicon layer is etched into an island and oxidized thermally to form an insulating film over the surface, thus completely insulating and separating the silicon layer. |
