Nanoscale Spectroscopy of Semiconductor Defects

Abstract

Wide-bandgap semiconductors are of great interest as a solution to meet the increasingly demanding requirements of power electronics. However, commercialization is challenged by the presence of extended defects. Many spectroscopic and microscopic techniques have been applied to the identification and characterization of these defects. These techniques are typically limited to providing either spectroscopic or microscopic information. Scattering-type scanning nearfield optical microscopy (s-SNOM) and nano Fourier transform infrared Spectroscopy (nano-FTIR) are nondestructive characterization methods that enable infrared microscopy and spectroscopy at spatial resolutions far exceeding the diffraction limit (< 20 nanometers). Characterization of two classes of extended defects, in-grown stacking fault (IGSF) and threading dislocations (TD) was performed using these techniques, resulting in the observation of a novel 3C-SiC IGSF and large strain induced phonon shifts in the vicinity of TDs.