| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a CMOS SRAM having a microscopic SOI structure.SOLUTION: A memory cell of a CMOS SRAM formed on a semiconductor substrate 1 via an insulation film 2 comprises: a flip flop for holding of information, composed of two pairs of a P-channel MISFET which has a gate electrode 19 integrally enclosing a part 6a of a lower semiconductor layer and a part 6b of an upper semiconductor layer of a dual semiconductor layer part via a gate insulation film 17 and in which ptype source-drain regions (9, 10) are formed in a semiconductor layer 5 in combination with an N-channel MISFET in which n type and ntype source-drain regions (24-27) are formed in a semiconductor layer 15; and a word transistor for reading or writing composed of two N-channel MISFETs each of which has a gate electrode 20 enclosing a part 16 of a single layer semiconductor layer via a gate insulation film 18 and in each of which n type and ntype source-drain regions (24-27) are formed in a semiconductor layer 14.</p> |
