Space charge formation in chromium-compensated GaAs sensors is investigated by the laser-induced transient current technique applying pulsed and DC bias. Formation of non-standard space charge manifested by an appearance of both negatively and positively charged regions in DC biased sensors was revealed during 5 ms after switching bias. Using Monte Carlo simulations of current transients we determined enhanced electron lifetime τ = 150 ns and electron drift mobility μ d = 3650 cm 2 Vs −1 . We developed and successfully applied a theoretical model based on fast hole trapping in the system with spatially variable hole conductivity.

中文翻译：

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铬补偿GaAs辐射探测器中的空间电荷形成

通过使用脉冲和直流偏置的激光感应瞬态电流技术研究了铬补偿的GaAs传感器中的空间电荷形成。在切换偏置后的5毫秒内发现了直流偏置传感器中同时出现负电荷区和正电荷区的现象，表明形成了非标准空间电荷。使用电流瞬变的蒙特卡洛模拟，我们确定了增强的电子寿命τ= 150 ns和电子漂移迁移率μd = 3650 cm 2 Vs -1。我们开发并成功地将基于快速空穴捕获的理论模型应用于具有可变空间电导率的系统。