PURPOSE: To obtain a sensor in which the number of picture elements is large and whose resolution is high by suppressing a crosstalk between the picture elements at an array type infrared sensor.

CONSTITUTION: Element isolation grooves 7 are formed between individual photodiodes 6 which have been formed on a p-Hg0.8Cd0.2Te layer. In addition, substrate electrodes 10 are formed in the groove parts. Since photocarriers generated in the p-Hg0.8Cd0.2Te layer 4 cannot pass the element isolation grooves 7, it is possible to suppress a crosstalk in which incident positions of infrared rays correspond to picture elements in a one-to-one manner. In addition, since the substrate electrodes are formed in the grooves, the potential of the individual photodiodes is stabilized and an irregularity in characteristic among the picture elements is reduced.