Investigation on defect levels in CdZnTe : Al using thermally stimulated current spectroscopy
Investigation on defect levels in CdZnTe : Al using thermally stimulated current spectroscopy
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DOI：
10.1088/0022-3727/43/34/345104
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发表时间：
2010-09
期刊：
影响因子：
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通讯作者：
Ruihua Nan;W. Jie;G. Zha;Tao Wang;Yadong Xu;Weihua Liu
中科院分区：
文献类型：
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作者：
Ruihua Nan;W. Jie;G. Zha;Tao Wang;Yadong Xu;Weihua Liu
采用热激电流谱（TSC）研究了半绝缘CdZnTe：Al单晶锭顶部、中部和尾部的缺陷能级。它们的陷阱签名，特别是热活化能，捕获截面和浓度，分别进行了表征和讨论，通过拟合测量的TSC光谱与同时多峰分析方法。此外，通过拟合室温以上的ln（I）与1/kT的关系图，发现来自顶部、中部和尾部的深施主能级EDD分别位于导带以下0.692 eV、0.659 eV和0.618 eV处。通过拟合电阻率随温度变化的线性曲线，确定了费米能级为0.716 ± 0.05 eV，这是由于EDD能级钉扎在带隙中间附近，从而导致了CdZnTe：Al晶锭中观察到的高电阻率。
Defect levels present in as-grown semi-insulating CdZnTe : Al samples, taken from the top, middle and tail of the same ingot, have been investigated by thermally stimulated current (TSC) spectroscopy. Their trap signatures, particularly the thermal activation energy, capture cross section and concentration, were characterized and discussed, respectively, by fitting the measured TSC spectra with the simultaneous multiple peak analysis method. Furthermore, the deep donor levels EDD from the top, middle and tail were found to be positioned at 0.692 eV, 0.659 eV and 0.618 eV below the conduction band, respectively, by fitting the ln(I) versus 1/kT plots above room temperature. The Fermi level was positioned at 0.716 ± 0.05 eV by fitting the linear plots of the temperature dependence of resistivity, which was pinned by the EDD level near the middle of the band gap, which in turn caused the observed high resistivity in the as-grown CdZnTe : Al ingot.