To provide a diode of a PiN structure which can prevent deterioration of characteristics as a variable resistance element or a variable capacity element and reduce leakage current.
In a semiconductor substrate, which has a P-type region 1, an N-type region 5 and a high resistivity region 4 inside and is formed into a P-i-N structure, an N-type low resistivity region 6 is formed in a circumference thereof adjacent to the P-type region 1 from the upper surface of a semiconductor substrate to a depth, which does not exceed the formation depth of the P-type region 1. Due to the existence of the resistivity region 6, an inversion phase is hardly generated during reverse biasing and the value of leak current can be made small, without having to increase the impurity concentration of the high resistivity region 4.
KUMAKUBO SATOSHI
KASAHARA TAKESHI
