| 摘要 |
PURPOSE:To reduce the size of a transistor, to decrease the capacity between paired substrate capacitors and other word line and to reduce power consumption by forming one side face of a first conductivity type semiconductor layer covering the partial upper face of an islandlike region over unidirectional arrays of the islandlike regions as a word line of one cell. CONSTITUTION:Regions divided into mesh by grooves 1 are formed in islandlike regions 16, a P-type semiconductor layer 17 is so formed to cover the partial upper face of the adjacent regions 16 as to bridge over between unidirectional arrays of the regions 16, and the layer 17 is isolated by a buried insulating film 18. Both the side faces of the layer made of the layer 17 and the film 18 are formed to be substantially perpendicular to each other, a gate insulating film 19 is formed on the upper face of the region 16 from the side faces, and the gate electrode of a cell transistor, i.e., a word line 3 is formed selectively on the insulating film. Thus, an electrostatic capacity opposed to a substrate is reduced, the size of a transistor is decreased, and an unnecessary charging current is eliminated to reduce power consumption. |
