Department of Physics, Chungnam National University, Daejeon, Republic of Korea.
Nanotechnology. 2019 Feb 15;30(7):075201. doi: 10.1088/1361-6528/aaf194. Epub 2018 Nov 16.
We discussed structural and electrical properties of PbS films deposited by chemical bath deposition. The crystallite size of our films measured by transmission electron microscope was as large as 0.2 μm in a lateral direction and 1 μm in a vertical direction, and we obtained a high mobility value of 60 cm V s at room temperature. We also demonstrated PbS photovoltaic infrared detectors using silver nanowires as transparent electrodes, whose spectral response was measured by Fourier transform infrared spectrometer. The cut-off wavelength was ∼3 μm at room temperature and ∼4 μm at 10 K. At 100 K, a pronounced photocurrent peak was observed at λ = 3.7 μm. Using finite difference time domain simulations, we demonstrated that silver nanowires worked as nano antennas for generating surface plasmons, resulting in the enhancement of photocurrent. The pronounced photocurrent peak wavelength corresponds to the wavelength where the silver nanowires were located near the constructive interference.
我们讨论了通过化学浴沉积法沉积的 PbS 薄膜的结构和电学性质。我们通过透射电子显微镜测量的薄膜的晶粒尺寸在横向方向上达到 0.2μm，在纵向方向上达到 1μm，并且在室温下获得了 60cm V s 的高迁移率值。我们还使用银纳米线作为透明电极演示了 PbS 光伏红外探测器，其光谱响应通过傅里叶变换红外光谱仪进行了测量。在室温下截止波长约为 3μm，在 10K 下约为 4μm。在 100K 时，在 λ=3.7μm 处观察到明显的光电流峰值。通过有限差分时域模拟，我们证明了银纳米线作为产生表面等离子体的纳米天线，从而增强了光电流。明显的光电流峰值波长对应于银纳米线位于建设性干扰附近的波长。
