Title :
Gamma-Ray Response of Semi-Insulating CdMnTe Crystals
Author :
Kim, KiHyun ; Cho, ShinHang ; Suh, JongHee ; Hong, Jinki ; Kim, SunUng
Author_Institution :
Brookhaven Nat. Lab., Upton, NY
fDate :
6/1/2009 12:00:00 AM
Abstract :
Semi-insulating Cd0.9Mn0.1Te:In crystals are grown by vertical Bridgman method. The segregation coefficient of Mn in CdTe is nearly 1 so that all the CdMnTe samples obtained from one ingot have nearly a same Mn composition. Also sulfur-based passivation effectively prevent the formation of Te-oxide but large amount of Mn exist as a MnO on the CdMnTe surface. The resistivity of CdMnTe samples are low 1010 Omegacm and well resolved 241Am gamma peaks are seen for all detectors. The difference in spectral response can be attributed to the effect of excess Te and conductivity change due to over-compensation induced by indium segregation in CdMnTe. The mobility-lifetime products evaluated from the dependence of peak location on the bias voltage are 1 times 10-3 cm2/V. The higher mobility-lifetime products in our CdMnTe crystals than other previous reports are assumed due to minimization of impurity contents in MnTe by several zone refining process.
Keywords :
cadmium compounds; crystal growth from melt; electrical conductivity; electrical resistivity; gamma-ray detection; indium; manganese compounds; passivation; semiconductor counters; ternary semiconductors; 7-ray detector; 241Am gamma rays; Cd0.9Mn0.1Te:In; crystal growth; electrical conductivity; electrical resistivity; impurity contents; mobility-lifetime; segregation; semiconductor detector; semiinsulating crystals; sulfur-based passivation; vertical Bridgman method; zone refining process; Conductivity; Crystals; Gamma ray detection; Gamma ray detectors; Impurities; Indium; Passivation; Refining; Tellurium; Voltage; CdMnTe; CdZnTe; X-ray detector; compensation; segregation coefficient; sulfur passivation;
Journal_Title :
Nuclear Science, IEEE Transactions on
DOI :
10.1109/TNS.2009.2015662
