Abstract

The data on the EPR, photoluminescence (PL), and current transfer in porous silicon (PS) on KDB-0.3 and KES-0.01 Si, which was oxidized by 10-min isochronous thermal annealing in air at temperatures T_ann from 20 to 900°C, as well as in HNO₃, are presented in order to further clarify the nature of P_b centers of nonradiative recombination. The maximum PL quantum yield was observed during the chemical oxidation of PS on KDB-0.3 silicon. An anticorrelation of the PL and EPR intensities of P_b centers is observed in the range T_ann = (20–300)°C. A nonmonotonic dependence of the EPR intensity of P_b centers on T_ann with a minimum at approximately 700°C is revealed. The weak PL of PS with T_ann of ~700°C accompanied by a minimum EPR signal from P_b centers means that other nonradiative-recombination centers arise after annealing. A decrease in the PS conductivity with an increase in T_ann is associated with the decomposition of Si fibers in PS into small granules, through which discrete tunneling of current carriers occurs.

中文翻译：

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多孔硅的EPR和发光

摘要

有关EPR，光致发光（PL）和KDB-0.3和KES-0.01 Si上多孔硅（PS）中电流传输的数据，这些数据在20到900的温度T _ann下于空气中通过10分钟等时热退火而被氧化提出了°C以及在HNO ₃中的含量，以进一步阐明非辐射重组的P _b中心的性质。在KDB-0.3硅上PS化学氧化过程中观察到最大PL量子产率。在T _ann =（20–300）°C的范围内，观察到了P _b中心的PL和EPR强度的反相关。P _b的EPR强度的非单调依赖性集中在T上_安以最小的在约700℃下被揭示。PS的PL弱，具有约700°C的T _ann，并伴随着来自P _b中心的最小EPR信号，这意味着退火后会出现其他非辐射复合中心。PS电导率随T _ann的增加而降低，与PS中的Si纤维分解成小颗粒有关，通过该颗粒出现电流载流子的离散隧穿。