摘要
利用原位透射电子显微术,研究了单根GaN纳米线I-V曲线与热效应、电击穿和压电效应的关系.在透射电子显微镜内构建一个基于GaN纳米线的金属-半导体-金属结构,测量单根纳米线的I-V曲线.随着连续测量次数的增加,纳米线的温度升高,电流逐渐增加,且I-V曲线由最初的不对称逐渐变得近乎对称;纳米线在较低电压下长时间连续测量后被击穿,I-V曲线对测量次数不再敏感.将GaN纳米线压弯后,电流明显下降,压电效应明显.分析表明,单根纳米线测量时的时间间隔和接触应力情况等是I-V曲线变化的重要因素.本研究可为极性纳米线的原位电学性质研究提供实验参考.
In situ transmission electron microscopy(TEM) was used to study the relationship between the I-V curves of single GaN nanowires and thermal effects, electrical breakdown and piezoelectric effects. A metal-semiconductor-metal structure based on GaN nanowires was constructed in TEM to measure the I-V curves of single GaN nanowires. When the temperature is increased, the current is increased gradually, and the I-V curve becomes nearly symmetrical gradually from the initial asymmetry. The nanowires are broken down after a long time of continuous measurement at low voltage, and the I-V curve is no longer sensitive to the number of measurements. Time interval and contact stress are important factors for the variation of I-V curves. This study can provide experimental reference for the in-situ electrical properties of polar nanowires.
引文
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