Priya K Shanmuga, Kola Lakshmi, Pal Subhajit, Biswas Pranab Parimal, Murugavel P
Department of Physics, Indian Institute of Technology Madras Chennai-600036 India
RSC Adv. 2020 Jul 7;10(43):25773-25779. doi: 10.1039/d0ra03968c. eCollection 2020 Jul 3.
Organic diisopropylammonium bromide (DIPAB) is a promising material with superior ferroelectric characteristics. However, the DIPAB continuous film, which is essential to explore its application potential, is challenging because its crystallization kinetics favors island-like microcrystalline growth. In this work, the continuous and uniform deposition of organic ferroelectric DIPAB film on a single crystalline Si(100) substrate is demonstrated by a thermal evaporation process. Structural and optical studies reveal that the film is -axis oriented with an optical bandgap of 3.52 eV. The topographic image displays well-connected grain-like surface morphology with ∼2 nm roughness. The ferroelectric domain studies illustrate the in-plane orientation of the domains, which is in accordance with -axis oriented film where polarization is along the in-plane -axis. The phase and amplitude responses of the domains display hysteresis and butterfly characteristics, respectively and thereby endorse the ferroelectric nature of the film. Importantly, it is demonstrated that the DIPAB film exhibits remarkable self-powered UV-Vis photodetector characteristics with responsivity of 0.66 mA W and detectivity of 2.20 × 10 Jones at 11.45 mW cm light intensity. The fabricated DIPAB film reported in this work can widen its application potential in self-powered photodetector and other optoelectronic devices.
有机二异丙基溴化铵（DIPAB）是一种具有优异铁电特性的有前途的材料。然而，对于探索其应用潜力至关重要的DIPAB连续薄膜，由于其结晶动力学有利于岛状微晶生长，因此颇具挑战性。在这项工作中，通过热蒸发工艺在单晶硅（100）衬底上实现了有机铁电DIPAB薄膜的连续均匀沉积。结构和光学研究表明，该薄膜沿c轴取向，光学带隙为3.52 eV。形貌图像显示出具有约2 nm粗糙度的连接良好的颗粒状表面形态。铁电畴研究表明了畴的面内取向，这与极化沿面内c轴的c轴取向薄膜一致。畴的相位和幅度响应分别显示出滞后和蝶形特性，从而证实了薄膜的铁电性质。重要的是，证明了DIPAB薄膜在11.45 mW/cm²的光强度下表现出显著的自供电紫外-可见光电探测器特性，响应度为0.66 mA/W，探测率为2.20×10 Jones。这项工作中报道的制备的DIPAB薄膜可以拓宽其在自供电光电探测器和其他光电器件中的应用潜力。
