Semiconductor Physics: Surface Photovoltage Spectroscopy of Semiconductors

Surface photovoltage spectroscopy (SPS) is a well-established contactless technique for semiconductor characterization, which relies on analyzing illumination-induced changes in the surface voltage. SPS traces its origins to the pioneering work of Brattain and Bardeen in the early 1950s, and was extended into a powerful spectroscopic tool by Gatos, Lagowski and Balestra in the early 1970s. It has been used as an extensive source of surface and bulk information on various semiconductors and semiconductor interfaces. In the following, we present the basic theory behind SPS, its experimental setup, and a range of its applications.