Department of Electronics and Telecommunications, Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim, Norway.
Nanotechnology. 2016 Sep 23;27(38):385703. doi: 10.1088/0957-4484/27/38/385703. Epub 2016 Aug 16.
Due to bandgap tunability, GaAsSb nanowires (NWs) have received a great deal of attention for a variety of optoelectronic device applications. However, electrical and optical properties of GaAsSb are strongly affected by Sb-related defects and scattering from surface states and/or defects, which can limit the performance of GaAsSb NW devices. Thus, in order to utilize the GaAsSb NWs for high performance electronic and optoelectronic devices, it is required to study the material and interface properties (e.g. the interface trap density) in the GaAsSb NW devices. Here, we investigate the low frequency noise in single GaAsSb NWs with self-induced compositional gradients. The current noise spectral density of the GaAsSb NW device showed a typical 1/f noise behavior. The Hooge's noise parameter and the interface trap density of the GaAsSb NW device were found to be ∼2.2 × 10(-2) and ∼2 × 10(12) eV(-1) cm(-2), respectively. By applying low frequency noise measurements, the noise equivalent power, a key figure of merit of photodetectors, was calculated. The observed low frequency noise properties can be useful as guidance for quality and reliability of GaAsSb NW based electronic devices, especially for photodetectors.
由于带隙可调谐性，GaAsSb 纳米线（NWs）在各种光电器件应用中受到了极大的关注。然而，GaAsSb 的电学和光学性质受到 Sb 相关缺陷以及表面态和/或缺陷散射的强烈影响，这可能限制 GaAsSb NW 器件的性能。因此，为了利用 GaAsSb NW 实现高性能的电子和光电器件，有必要研究 GaAsSb NW 器件中的材料和界面特性（例如界面陷阱密度）。在这里，我们研究了具有自诱导成分梯度的单个 GaAsSb NW 中的低频噪声。GaAsSb NW 器件的电流噪声谱密度表现出典型的 1/f 噪声行为。发现 GaAsSb NW 器件的 Hooge 噪声参数和界面陷阱密度分别约为 2.2×10(-2)和 2×10(12) eV(-1) cm(-2)。通过应用低频噪声测量，计算了光电探测器的关键性能指标之一——噪声等效功率。所观察到的低频噪声特性可作为基于 GaAsSb NW 的电子器件（特别是光电探测器）的质量和可靠性的指导。
