Semiconductor sensor

Abstract

A semiconductor sensor includes a field-effect transistor for detecting a physical quantity such as pressure, strain, acceleration or the like. The field-effect transistor is disposed on an elastically deformable portion of a cantilevered semiconductor substrate. A detected signal generator generates a signal representing a change in a drain current of the field-effect transistor in response to a stress which is applied to the field-effect transistor due to elastic deformation of the semiconductor substrate. The field-effect transistor may be supplied with a fixed gate bias voltage and an integrator may generate a signal representing an integral of the drain current for temperature compensation. Alternatively, an integrator may generate a signal representing an integral of the drain current, and a gate bias voltage may be applied to the field-effect transistor so that the signal generated by the integrator will be of a predetermined value for automatic temperature compensation. As a further alternative, a self-bias circuit may be connected between the field-effect transistor and the detected signal generator for applying a gate self-bias voltage to the field-effect transistor for automatic temperature compensation.