摘要
Thermal annealing in Te vapor atmosphere was adopted to improve the properties of indium-doped Cd_(1-x)Mn_xTe(x=0.2,CdMnTe) wafers grown by the vertical Bridgman method.The wafers before and after annealing were characterized by measuring the Te inclusions,etch pit density(EPD),Mn composition,resistivity, and impurity.IR transmission microscopy and EPD measurements revealed that the densities of Te inclusions reduced from(5-9)×10~4 cm^(-3) to(2-4)×10~4 cm^(-3) and EPD from 10~5 cm^(-2) to 10~4 cm^(-2) after annealing. NIR transmission spectroscopy showed that the Mn composition increased by 0.002-0.005 mole fractions during the annealing.The resistivity of the wafers improved from(2.0-4.5)×10~8Ω·cm to(1.7-3.8)×10~9Ω·cm,which suggested that the deep-level donor of Te antisites was successfully introduced after annealing.Inductively coupled plasma-mass spectrometry(ICP-MS) revealed that the concentrations of impurities in the wafer decreased,which indicated the purifying effects of Te vapor annealing on the wafers.All the results demonstrate that the Te vapor annealing of the indium-doped CdMnTe crystal has positive effects on the crystallinity,resistivity and purity of CdMnTe wafers.
Thermal annealing in Te vapor atmosphere was adopted to improve the properties of indium-doped Cd_(1-x)Mn_xTe(x=0.2,CdMnTe) wafers grown by the vertical Bridgman method.The wafers before and after annealing were characterized by measuring the Te inclusions,etch pit density(EPD),Mn composition,resistivity, and impurity.IR transmission microscopy and EPD measurements revealed that the densities of Te inclusions reduced from(5-9)×10~4 cm^(-3) to(2-4)×10~4 cm^(-3) and EPD from 10~5 cm^(-2) to 10~4 cm^(-2) after annealing. NIR transmission spectroscopy showed that the Mn composition increased by 0.002-0.005 mole fractions during the annealing.The resistivity of the wafers improved from(2.0-4.5)×10~8Ω·cm to(1.7-3.8)×10~9Ω·cm,which suggested that the deep-level donor of Te antisites was successfully introduced after annealing.Inductively coupled plasma-mass spectrometry(ICP-MS) revealed that the concentrations of impurities in the wafer decreased,which indicated the purifying effects of Te vapor annealing on the wafers.All the results demonstrate that the Te vapor annealing of the indium-doped CdMnTe crystal has positive effects on the crystallinity,resistivity and purity of CdMnTe wafers.
基金
supported by the National Natural Science Foundations of China(No.50902091)
the Science and Technology Commission of Shanghai,China(No.11530500200)
the Innovation Program of Shanghai Municipal Education Commission,China(No.12ZZ096)
the Innovative Foundation of Shanghai University,China
