The non-ohmic hopping conductivities of a large number of samples of lightly doped by various impurities (P, As, Sb, B and Ga) and weakly compensated nand p-type Si were investigated. The current-voltage (I-TI) characteristics appeared to be different in two temperature regions typical for the studies of Ohmic hopping conductivity: the low-temperature hopping conductivity region with a constant activation energy epsilon (3) (the epsilon (3) region) and the relatively high-temperature hopping conductivity saturation region (the s region). In the epsilon (3) region the conductivity increases with increasing field owing to a Poole-Frenkel-like lowering of the activation energy. In the s region the conductivity decreases with increasing field and shows a negative differential conductance (low-frequency current oscillations have been observed) according to Aladashvili et al. (1988. JETP Lett.. 47, 390) as predicted by Nguyen and Shklovskii. It is shown that low-frequency current oscillations are associated with 'hopping' domain periodic formation and travel in the bulk of the sample; the hopping domain is of triangular shape parallel to the external field, with equal leading and back edges. Estimates give the velocity c = 0.25 cm s(-1), the domain width d = 150 mum and the average field E = 300 V cm(-1), The mobility of the hopping carriers is measured. [References: 21]
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机译:研究了大量轻掺杂各种杂质(P,As,Sb,B和Ga)以及弱补偿的n和p型Si的样品的非欧姆跳跃电导率。在研究欧姆跳跃电导率的两个典型温度区域中,电流-电压(I-TI)特性似乎有所不同:具有恒定活化能epsilon(3)的低温跳跃电导率区域(epsilon(3)区域) )和相对高温的跳变电导率饱和区域(s区域)。在ε(3)区域,电导率由于激活能的类似于Poole-Frenkel的降低而随电场的增加而增加。根据Aladashvili等人的研究,在s区域,电导率随电场的增加而降低,并显示出负的差动电导(已观察到低频电流振荡)。 (1988. JETP Lett .. 47,390)由Nguyen和Shklovskii预测。结果表明,低频电流振荡与“跳跃”域的周期性形成和样品的大部分传播有关。跳跃域是平行于外部场的三角形,前边缘和后边缘相等。估计给出速度c = 0.25 cm s(-1),畴宽d = 150 mum,平均场E = 300 V cm(-1),测量了跳跃载流子的迁移率。 [参考:21]
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