Qiao Shuang, Liu Jihong, Li ZhiQiang, Wang ShuFang, Fu GuangSheng
Opt Express. 2017 Aug 7;25(16):19583-19594. doi: 10.1364/OE.25.019583.
As an interesting one dimensional ribbon material, SbS has recently attracted much attention in recent years due to its exciting optical properties. However, SbS-based photovoltaic or photoelectronic devices are still in research, and there are many things unknown to us and need to be well studied. In this work, the glass/FTO/CdS/SbS/Au structures were successfully prepared with different SbS thicknesses, and the lateral photovoltaic effect (LPE) was firstly observed in this structure, suggesting its great potential in position sensitivity detectors (PSD). It is demonstrated that the crystallinity of SbS film increases, and SbS film tends to be vertical ribbon orientation with increasing thickness. Owing to the strong light absorption of the thicker SbS film and its one dimensional ribbon like crystal structure, the LPE in the glass/FTO/CdS/SbS/Au structure improves with increasing SbS thickness from 350 nm to 800 nm, and the glass/FTO/CdS/SbS(800 nm) structure exhibits an unprecedented performance with position sensitivity as large as 2230.4 mV/mm. Moreover, the time response of photovoltage was also firstly measured in this structure, it is observed that both the rise time and the fall time decrease with increasing thickness from 350 nm to 800 nm, and then increase quickly for 1100 nm film, further verifing that the SbS thickness-dependent LPE is strongly dependent on the carriers' longitudinal transport time. The very large LPE and the relatively fast response speed observed in the glass/FTO/CdS/SbS(800 nm)/Au structure unveils its great potential applications in the optoelectronic detectors and also bring an insight that the suitable thickness is very crucial in SbS-based devices.
作为一种有趣的一维带状材料,近年来,硫化锑(SbS)因其令人兴奋的光学特性而备受关注。然而,基于硫化锑的光伏或光电器件仍在研究中,我们对其还有很多未知之处,需要深入研究。在这项工作中,成功制备了具有不同硫化锑厚度的玻璃/FTO/CdS/SbS/Au结构,并首次在该结构中观察到横向光伏效应(LPE),这表明其在位置敏感探测器(PSD)方面具有巨大潜力。结果表明,随着厚度增加,硫化锑薄膜的结晶度提高,且硫化锑薄膜趋于垂直带状取向。由于较厚的硫化锑薄膜具有较强的光吸收及其一维带状晶体结构,玻璃/FTO/CdS/SbS/Au结构中的横向光伏效应随着硫化锑厚度从350nm增加到800nm而增强,玻璃/FTO/CdS/SbS(800nm)结构表现出前所未有的性能,位置灵敏度高达2230.4mV/mm。此外,还首次在该结构中测量了光电压的时间响应,观察到上升时间和下降时间均随着厚度从350nm增加到800nm而减小,然后对于1100nm的薄膜迅速增加,进一步验证了与硫化锑厚度相关的横向光伏效应强烈依赖于载流子的纵向传输时间。在玻璃/FTO/CdS/SbS(800nm)/Au结构中观察到的非常大的横向光伏效应和相对较快的响应速度揭示了其在光电器件中的巨大潜在应用,也带来了一个见解,即合适的厚度在基于硫化锑的器件中非常关键。