Title :
Photocurrent and Surface Photovoltage Spectroscopy Investigations of CdTe-Based Compounds
Author :
Cavallini, Anna ; Castaldini, Antonio ; Cavalcoli, Daniela ; Fraboni, Beatrice
Author_Institution :
Dept. of Phys., Bologna Univ., Bologna
Abstract :
The potentiality of photocurrent (PC) and surface photovoltage spectroscopy (SPS) analyses in the determination of the band gap of CdTe-based ternary alloys was investigated. Both methods can detect band-to-band and defect state-to-band transitions. The role played by the surface states in both experimental methods has been studied since it may significantly alter the results. The below-band gap energy levels have also been detected by PC and SPS and the different information that can be obtained in the two cases has been discussed. The results obtained by PC and SPS have been compared in order to extract the contribution of the surface and bulk states.
Keywords :
II-VI semiconductors; cadmium compounds; deep levels; energy gap; particle detectors; photoelectron spectra; semiconductor counters; surface photovoltage; surface states; wide band gap semiconductors; CdTeJk; band gap; band-band transition; charge trapping; deep levels; defect state-band transition; photocurrent spectroscopy; radiation detectors; surface photovoltage spectroscopy; surface states; ternary alloys; Detectors; Electrodes; Optical materials; Optical noise; Optical surface waves; Photoconductivity; Photonic band gap; Spectroscopy; Spontaneous emission; Temperature; Charge trapping; deep levels; radiation detectors;
Journal_Title :
Nuclear Science, IEEE Transactions on
DOI :
10.1109/TNS.2007.905171
