Array type charge extraction device for infra-red detection

A plurality of infra-red detectors having storage capabilities are arranged in an array having X and Y address lines and a signal readout line. The detector elements have a semiconductor substrate of extrinsic material such as suitably doped silicon, and operate to store and provide readout of signal information using majority carriers, there being no requirement for depletion regions or P-N junctions. Majority carrier diffused regions are formed along the front surface of the substrate, the X and Y address lines and the signal line being placed adjacent to these diffused layers as well as terminals for applying a bias voltage and for forming a storage capacitor for each of these detector elements. Bias is applied in a polarity such as to attract majority carriers generated by the infra-red radiation to the surface for storage in the storage capacitor, the stored carriers providing a readout signal on the signal line when an addressing signal appears on the X and Y lines.