MAPbCl_(3)单晶光电探测器的制备及表征

Preparation and characterization of MAPbCl_(3) single crystal photodetector

作为新一代半导体材料,金属-卤化物钙钛矿以其大的光吸收系数、长的载流子扩散长度和高载流子迁移率等优异特性被研究者广泛关注。与多晶相比,钙钛矿单晶材料具有更低的缺陷态密度并且没有晶界,有望提高光电探测器性能。为了研究MAPbCl_(3)单晶的光电探测性能,采用反向升温法制备了大块MAPbCl_(3)单晶,然后采用真空热蒸发法在其表面蒸镀上Au的叉指电极,制成了Au/MAPbCl_(3)/Au结构的光电探测器,最后对其进行了光电性能表征。结果表明,采用反向升温法制备得到的单晶在紫外光和紫光波段中都表现出了很强的吸收,光谱显示出清晰的带边缘切边,同时对波长大于吸收边的光波段光线有较好的透过性,透过率大于50%;器件在5 V电压下响应峰值波长为415 nm,最高响应度为1.24 mA/W,最高外量子效率为3.1%,器件稳定性较好。

As a new generation of semiconductor materials,metal-halide perovskite has attracted wide attention of researchers due to its large light absorption coefficient,long carrier diffusion length and high carrier mobility.Compared with polycrystalline,perovskite single crystal material has a lower defect state density and no grain boundaries,which is expected to improve the performance of photodetectors.In order to study the photoelectric detection performance of MAPbCl_(3) single crystal,large MAPbCl_(3)single crystal was prepared by reverse heating method,and then Au interdigital electrode was evaporated on its surface by vacuum thermal evaporation method to make Au/MAPbCl_(3)/Au photodetector.Finally,its photoelectric properties were characterized.The results show that:the single crystal prepared by the reverse heating method exhibits strong absorption in both the ultraviolet and violet light bands;the spectrum shows clear band edge trimming,and at the same time,the wavelength of light is greater than the absorption edge.It has good permeability;and the transmittance is greater than 50%.The response peak wavelength of the device under 5 V voltage is 415 nm,the highest responsivity is 1.24 mA/W,the highest external quantum efficiency is 3.1%,and the device stability is good.