论文标题
通过MACE工艺制备的硅纳米线的结构和电行为
Structure and electrical behavior of silicon nanowires prepared by MACE process
论文作者
论文摘要
我们报告了通过金属辅助化学蚀刻（MACE）方法制备的硅纳米线阵列的结构和电特性，该方法通过横截面扫描电子显微镜（SEM）和高分辨率X射线衍射（HR-XRD）进行了研究。 SEM显微照片分别在1.5分钟和5分钟后蚀刻时间后，长度为700 nm和1000 nm的合并平行纳米线阵列，长度为700 nm和1000 nm。 Si（004）周围的X射线相互空间图（RSM）互惠晶格点表示存在0D结构缺陷，而不是扩展缺陷。光致发光光谱在1.70 eV和1.61 eV处表现出发射带，在较长的电线的情况下，强度明显更高，并且与较不良的表面相关。瞬态光致发光光谱显示两个SINW阵列的平均寿命为60 $ $ $ s，111 $ $ $ s，在最新情况下与较大的缺陷状态相关。纳米线的I -V特性显示出一个回忆行为，其施加电压扫描速率在5V/s -0.32V/s范围内。我们将这种行为归因于控制载体浓度的陷阱，并使用等效电路对此效果进行建模。可见域，405 nm -650 nm的激发波长下的光生过程以及在20-100 mW/cm $^2 $范围内的光强度下，为陷阱状态提供了进一步的见解。
We report on the structure and electrical characteristics of silicon nanowire arrays prepared by metal assisted chemical etching (MACE) method, investigated by cross-sectional scanning electron microscopy (SEM) and high resolution X-ray diffraction (HR-XRD) methods. SEM micrographs show arrays of merged parallel nanowires, with lengths of 700 nm and 1000 nm, resulted after 1.5 min and 5 min etching time, respectively. X-ray reciprocal space maps (RSMs) around Si (004) reciprocal lattice point indicate the presence of 0D structural defects rather than of extended defects. The photoluminescence spectra exhibit emission bands at 1.70 eV and 1.61 eV, with intensity significantly higher in the case of longer wires and associated with the more defected surface. The transient photoluminescence spectroscopy reveals average lifetime of 60 $μ$s and 111 $μ$s for the two SiNW arrays, which correlate with a larger density of defects states in the latest case. The I-V characteristics of the nanowires, show a memristive behavior with the applied voltage sweep rate in the range 5V/s - 0.32V/s. We attribute this behavior to trap states which control the carrier concentration, and model this effect using an equivalent circuit. Photogeneration processes under excitation wavelengths in visible domain, 405 nm - 650 nm, and under light intensity in the range 20 - 100 mW/cm$^2$ provided a further insight into the trap states.
