| 摘要 |
PURPOSE: To make the gate length of a depression gate smaller than the gate length of a storage gate by forming the active area of a transistor, partially removing a bottom part insulating body, exposing the contact hole of the storage gate, heaping a metallic film on the entire wafer and partially removing the metallic film. CONSTITUTION: A phosphorus doped amorphous silicon layer 12 is heaped as the contact layer of a source and a drain, a photoresist layer 13 is heaped at the peak part of the amorphous silicon layer 12, the amorphous silicon layer 12 is etched, all the parts other than the lower layer part of the photoresist layer 13 are removed and the photoresist layer 13 is removed. Then, the photoresist layer 14 is heaped on the entire wafer 10 and a lower part insulation layer 6 is etched. Thus, all the parts other than the part protected by the photoresist layer 14 are removed, an opening to the storage gate 4 is formed and the photoresist 14 is removed. Then, the metallic film 16 is heaped on the entire wafer, the photoresist layer 18 is heaped, the metallic film 16 is etched and all the parts other than the lower layer part of the photoresist layer 18 are removed.
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