Patterned Growth Of Perovskite Film Arrays And Its Application

Recently,practical device application of perovskites in integrated optoelectronic devices such as artificial eyes,electronic skin,camera modules,and digital display intrigues an increasing demand for optoelectronic device arrays.The conventional photolithography process,consisting of photoresist spin-coating,baking,and developing,have been extensively employed for the patterning of inorganic semiconductor in the current semiconductor industry.However,it has been ruled out for the patterning of perovskite materials due to the solubility of perovskites in many polar and protic solvents and the moisture sensitivity of the organic component.We proposed a PDMS stamp oligomers assisted method for the patterned growth of perovskite thin film arrays,which has been successfully applied in the field of visible light trajectory tracking and real-time image sensing.The detailed research results are as follows:1.The pre-designed patterned PDMS stamp was imprinted on the surface of the hydrophilic treated substrate,which was then kept in a vacuum drying oven(0.03MPa,28?,4 h).A patterned hydrophilic and hydrophobic substrate was obtained through the transferring of uncured PDMS oligomer molecules to the surface of the substrate.Through the spin coating method,the scheme is applied to different perovskite materials(MAPbI₃,FA_0.85Cs_0.15Pb I₃and CH₃NH₃Pb I_3-xCl_x)and different target substrates(SiO₂,FTO,ITO and mica),and the patterned growth of the perovskite film array can be successfully realized.2.MAPbI₃ thin film arrays were patterned grown on the pre-treated SiO₂/Si substrate through the PDMS oligomer assisted method.Photodetectors array was fabricated by depositing the parallel Au electrodes array with a certain channel length onto the obtained MAPbI₃ perovskite film array through a shadow mask.Electrical characterization revealed that the device has good photoelectric properties in the visible light range,and exhibits the most obvious photoresponse to incident light around 660 nm,presenting a responsivity of up to 2.83 AW^-1,external quantum efficiency of 5.32×10²%,specific detection of 5.4×10¹² Jones and a fast response speed(?_r/?_f=52.7/57.1?s).In addition,the channel currents of all pixels in the dark and under uniform white light illumination were recorded.The majority of them have similar I_light/I_darkratios,suggesting the satisfactory uniformity of the perovskite thin film arrays.3.An addressable 8×8 perovskite photodetectors array was fabricated on a SiO₂/Si substrate with a predeposited complex metal circuit,which has been successfully used in the trajectory tracking of the visible light spot moving in the"Z"shape.By means of the customized data acquisition system and imaging system,the static real-time imaging of different letters including“H”,“F”,“U”and“T”was successfully realized under illuminations of white light,450 nm,660 nm and 810 nm,respectively.All images presented the satisfactory spatial resolutionThe uncured PDMS oligomer molecule assisted patterned growth provides a convenient and effective strategy for the growth of perovskite thin film arrays,which facilitate the application of perovskite materials in field of light track tracking and image sensing.