| 摘要 |
PURPOSE:To prevent the breakdown of informations at high potential stored in a memory cell by forming a source and a drain in a MOSFET to a reverse conduction type semiconductor layer shaped to the surface section of a semiconductor substrate and arranging a capacitor to a V-groove. CONSTITUTION:N<+> type layers 61, 62 as a drain and a source in a MOSFET 6 are formed onto a P<-> type semiconductor layer 15 shaped onto the surface of an N-type semiconductor substrate. On the other hand, a capacitor 7 consisting of conductive layers 71, 73 formed through an insulating film 72 are disposed onto an insulating film 53 added onto the surface of a groove 52 shaped in the direction of the substrate 5 from the surface of the layer 51. When a reverse bias is applied between the layer 51 and the substrate 5 in the constitution, a depletion layer 55 is formed to the lower section of the film 53 and extending over a section between the layer 51 and the substrate 5. When the surface is irradiated by alpha-particles under the state, alpha-rays intrude to the groove 52 section and electrons are generated in the depletion region of the lower section of the film 53, the electrons flow in toward the substrate 5 further brought to high potential along the electric field of the layer 55. Accordingly, informations stored in the capacitor are not lost. |
