Image Capture Devices Based on Charge Storage at Semiconductor-Ferroelectric Interfaces

This work shows that semiconductor-ferroelectric (SC-FE) charge storage devices are promising candidates for image capture and irradiance measurements. Incident radiation generates electron-hole pairs in the semiconductor layer, but as distinct from semiconductor pn-junctions, photocarriers are trapped at the SC-FE interface and decrease the depolarization field of the FE layer and the band bending at the interface that does not need any power supply. Since the decrease in band bending is proportional to the incident irradiance, the readout can be carried out after a certain measurement time. The paper discusses the possibilities for both a capacitive and a resistive readout. The spectral responsitivity of such SC-FE junction devices may be well designed by choosing a suitable semiconductor layer with high radiation absorption in the desired spectral range.