Mid-IR-laser microscopy as a tool for defect investigation in bulk semiconductors

A non-destructive optical technique described in this paper is an effective new tool for the investigation of defects in semiconductors. The basic instrument for this technique—a mid-IR-laser microscope—being sensitive to accumulations of free carriers enables the study of both accumulations of electrically-active defects or impurities in bulk semiconductors and doped domains in semiconductor structures. The optical beam induced scattering mode of this microscope is designed for the investigation of recombination-active defects but unlike EBIC it requires neither Schottky barrier or p–n junction nor special preparation of samples