| 摘要 |
PURPOSE:To prevent the formation of a parasitic thyristor due to radiation by completely sealing and shielding either one of CMOSFETs with a protective cup which has a closed curved surface formed of a low resistance layer. CONSTITUTION:An SiO2 film 3 is covered on an N type epitaxial layer 2 on a P<+> type Si substrate 1, a hole 10 is opened, and a P<+> type protective ring 4 is formed. A hole 10' is opened, P<+> type source and drain layers 6, 7 are formed, a hole 10''' is opened, and a P-well 5 is formed. Further, a hole is newly opened, N is diffused, a source layer 6' and a drain layer 7' are formed in the well 5, and a P type channel stopper 8 is provided at the layer 2. Then, the electrodes and aluminum wiring pattern 9 for connecting the electrodes are formed to complete it. In the CMOSIC according to this construction, even if electron and hole occur due to incident radiation, one FET is completely sealed by the low resistance protective cup. Accordingly, a malfunction due to the formation of a parasitic thyristor can be entirely eliminated. |
