A semiconductor device includes a first semiconductor layer of a first conductivity type having a primary surface and having a sensor therein, a second semiconductor layer of a second conductivity type having a circuit element formed therein. The second semiconductor layer is formed at a same side of the primary surface of the first semiconductor layer. The device further includes an insulating layer formed between the first semiconductor layer and the second semiconductor layer. The insulating layer is disposed on the primary surface of the first semiconductor layer and surrounds the circuit element, and includes a charge-attracting semiconductor pattern of the first conductivity type that is disposed near the circuit element so as to attract electrical charges generated in the insulating layer.