Effect of donor-complex-defect-induced dipole field on InAs/GaAs quantum dot infrared photodetector activation energy
Effect of donor-complex-defect-induced dipole field on InAs/GaAs quantum dot infrared photodetector activation energy
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DOI：
10.1063/1.2747199
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发表时间：
2007-06
影响因子：
4
通讯作者：
Zhiya Zhao;C. Yi;K. R. Lantz;A. Stiff-Roberts
中科院分区：
文献类型：
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作者：
Zhiya Zhao;C. Yi;K. R. Lantz;A. Stiff-Roberts
为了了解掺杂在量子点红外探测器中的作用，对三种量子点肖特基二极管(未掺杂、增量掺杂和调制掺杂)进行了研究。只在掺杂的二极管中观察到了施主-络合缺陷(DX)中心。随着外加偏压的增加，掺杂样品的暗电流迅速增加，量子点激活能急剧下降。激活能的降低可能与量子点中带正电荷的dx中心和电子之间的偶极场有关。提出了一种输运机制来解释在掺杂样品中观察到的激活能偏置关系。
In order to understand dopant incorporation in quantum dot infrared photodetectors, three quantum dot (QD) Schottky diodes (undoped, delta doped, and modulation doped) have been investigated. Donor-complex-defect (DX) centers have been observed by photocapacitance quenching in the doped diodes only. When the applied bias increases, the doped samples show a rapid increase in dark current and a resulting dramatic decrease in QD activation energy. The activation energy reduction could be related to a dipole field between positively charged DX centers and electrons in QDs. A transport mechanism is proposed to explain the observed activation energy bias dependence in the doped samples.