PURPOSE: To achieve high speed operation without losing transistor characteristics by providing a potential for a semiconductor substrate and not allowing the capacitance of a depletion layer between a drain and a semiconductor substrate to increase.
CONSTITUTION: A source region 2 is not so deep that it does not reach an insulating substrate 4. Ions whose type is similar to a semiconductor substrate are injected into a region adjacent to such source region 2 and opposite to a gate electrode 1 relative to a drain region 3. Accordingly, a potential for the semiconductor substrate can be obtained from such ion injected region, and the kink effect can be prevented. In depletion layers 6, 7 which will become load capacitance for the transistor, since the drain region 3 is so constructed that it reaches the insulating substrate 4, depletion layer capacitance in this region is small. This prevents the transistor from losing its characteristics, whereby the transistor capable of operating at high speeds can be constructed on the insulating substrate.
HOSOYA SHIRO
KIMURA MASATOSHI
