| 摘要 |
PURPOSE:To improve resistance to alpha-ray by providing the memory cell of an SRAM with capacitors constituted of backward biased diodes. CONSTITUTION:A p<+> type diffusion layer is formed on an n-type epitaxial growth layer n-epi, and a pn junction is constituted. The p<+> type diffusion layer is not connected with a word line WL but connected with a p-type semiconductor substrate p-SUB. As the result, diodes D3, D4 connected between the p-SUB and nodes N1, N2 are formed, and backward biased since the potential of the substrate p-SUB is lower than the nodes N1, N2. By this constitution, backward bias diodes D3, D4 are obtained, and large capacitors are connected with the nodes N1, N2, so that resistance to alpha-ray can be increased. |
