Investigation of the surface-potential distribution of epitaxial CdHgTe films

Abstract

The epitaxial growth of CdHgTe films is accompanied by the formation of V defects whose density and electronic properties greatly affect the characteristics of a terminal device based on the given material. Scanning atomic-force microscopy techniques are proposed to investigate how electronic properties vary in the V-defect region of an epitaxial CdHgTe film. It is experimentally demonstrated that variations in the component composition of individual crystallites generating V defects create not only the complex spatial distribution of a potential field but also a potential barrier along the crystallite periphery. The given barrier must alter the charge-carrier exchange between crystallites, appreciably changing the current distribution over the V-defect area.