High-quality GaN micro/nano columns were prepared with self-organized catalytic-free method. Young’s modulus of GaN nanocolumns were measured under both compressive stress and tensile stress. It was found that the Young’s modulus decreases with the increasing of nanocolumn diameter due to the increase of face defect density. Furthermore, we measured the piezoelectric properties and found that there was a 1000-fold current increase under a strain of 1% with a fixed bias voltage of 10 mV. Based on the Schottky Barrier Diode model, we modified it with the effect of polarization charge, image charge and interface state to analyze the experiment results which reveals that the strong piezopolarization effect plays an important role in this phenomenon. Therefore, the GaN nanocolumns has a great prospect to be applied in high-efficiency nanogenerators and high-sensitivity nanosensors.

中文翻译：

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GaN微纳米柱的超高灵敏度压电效应研究。

采用自组织无催化方法制备了高质量的GaN微/纳米柱。在压缩应力和拉伸应力下都测量了GaN纳米柱的杨氏模量。发现由于表面缺陷密度的增加，杨氏模量随着纳米柱直径的增加而降低。此外，我们测量了压电性能，发现在固定偏压为10 mV的情况下，在1％的应变下电流增加了1000倍。基于肖特基势垒二极管模型，我们通过极化电荷，图像电荷和界面态的影响对其进行了修改，以分析实验结果，结果表明强压电极化效应在该现象中起着重要作用。因此，