A systematic study of the electronic characteristics of grain‐boundary interface states was performed on a commercial zinc oxide varistor material using zero‐bias deep level transient spectroscopy, current‐voltage, high‐frequency capacitance, and infrared reflectance techniques. Interface states, which act as deep acceptors, were found to exist at 0.97±0.12 eV below the conduction‐band edge. The capture cross section is approximately 4×10−15cm2. Characteristics of the interface states were determined as a function of the voltage of the trap filling pulse, which was varied from 0.9 to 2.0 V per grain boundary. It is shown that the trap energy is independent of the voltage of the pulse, while the apparent trap density increases with increasing voltage from 1.9 to 7.4×1011cm−2. The results presented here indicate that this interface level is monoenergetic.
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机译:采用零偏置深能级瞬态光谱、电流、连字符电压、高频电容和红外反射技术,对商用氧化锌压敏电阻材料的晶粒和边界界面态的电子特性进行了系统研究。发现作为深受体的界面态存在于导通带边缘以下 0.97±0.12 eV 处。捕获横截面约为 4×10−15cm2。界面状态的特征被确定为陷阱填充脉冲电压的函数,该脉冲在每晶界0.9至2.0 V之间变化。结果表明,陷阱能量与脉冲电压无关,而表观陷阱密度随电压的增加而增加,从1.9增加到7.4×1011cm−2。这里给出的结果表明,该界面能级是单能的。
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