| 摘要 |
PURPOSE:To obtain a memory cell strong to alpha rays by mounting a means which prevents the reaching of electrons or holes generated by alpha rays to the memory cell or a bit line in a substrate used for a semiconductor memory. CONSTITUTION:A P<-> type silicon layer 8, the concentration of impurities in boron therein is 7X10<14>/cm<3> and thickness thereof is 4mum, is formed on the P<++> type silicon substrate 1', the concentration of impurities in boron therein is 2.8X10<17>/cm<3>, through a gaseous phase growth method. The dynamic random access memory using a MOS transistor is shaped to the P<-> type silicon layer. |
