| 摘要 |
PURPOSE:To prevent the FF-type memory content distruction through alpha-rays by a method wherein in a multiemitter transistor the capacitance between the emitter connected with a word line and the base is made larger than that between the emitter connected with a digit line and the base. CONSTITUTION:In an N epitaxial layer 12 surrounded by a field oxide film 12, a transistor P base 15 and N<+> emitter 18, 19 are formed and a P-layer 16, P-type resistance layer 17 of a diode D2 are prepared. The emitter 18 is made wider than the emitter 19 in area and the junction capacity is made C2>C1. Further, before a base layer 15 is formed, a relatively deep base part 15A is formed under the layer 18, and when the base breadth is enlarged and the diffusion capacity is increased, the memory cell information inversion because of alpha-rays irradiation becomes hard to occur and the memory cell of strong tightness against malfunction can be gained. Moreover, there is little function speed drop because of increased junction capacitance of the emitter 18 connected with a word line. |
