Influence of surface treatment of CdZnTe for the radiation detector

CdZnTe is the most promising material for the room temperature radiation detector. Previously many studies have been done for the fabrication process of CdZnTe radiation detector. Usually the CdZnTe surface was mechanically polished and etched with bromine/methanol. The Au or Pt was deposited to make the metal contact on the crystal. From the previous works, it was concluded that the dark current of the CdZnTe detector is greatly influenced by the surface roughness. We study the fabrication process of CdZnTe detector with indium electrode contacts. The dependency of the dark current on the surface treatment was studied. The CdZnTe crystal is treated thermally during the electrode deposition, and the effect of the thermal treatment to the detector performance is studied.