Current Reduction of CdZnTe via Band Gap Engineering

CdZnTe-based gamma detectors require a reduction of electronic noise contributed by apparent device and surface leakage current, especially for advanced readout schemes such as the Co-planar Grid or Pixelated Grid. In this work, we describe a combination of surface treatments and amorphous semiconductor layers that result in a reduction of both apparent device and surface leakage current compared to metal contacts on Br:MeOH etched devices. Characterization by scanning electron microscopy (SEM), spectroscopic ellipsometry (SE), x-ray photoelectron spectroscopy (XPS), current-voltage (IV), and pulse height spectra is performed.