【作者】 刘飞；

【导师】 胡伟； 李天望；

【作者基本信息】 湖南大学 ， 集成电路工程（专业学位）， 2021， 硕士

【摘要】 光电器件,是一种将光信号转换为电信号的器件,做为光芯片的关键元件,它的制备工艺和性能将直接影响到光芯片的产出和质量。以不同的光吸收材料为基础,通过优化薄膜的制备工艺提高光探测器的性能,是半导体光电器件的主要研究方向。自2009年第一块钙钛矿太阳能电池诞生以来,钙钛矿优异的光电特性一直被深入发掘,包括大的光吸收系数、带隙可调等。作为核心光敏层,其在光探测器、薄膜晶体管等领域具有广泛的应用。碘化铅作为一种典型的钙钛矿衍生物,由于其在室温下具有大的密度和较高的原子序数等特点,碘化铅薄膜通常可以为大多数应用提供基本的物理信息,也是一种非常有前途的半导体材料,同样适用于光探测器。电流体动力学(EHD)打印技术作为一种新兴的3D打印技术,因具有无需掩模、操控简单、效率高、油墨兼容性好、材料利用率高、促进极性结晶、能大范围沉积等巨大优势,在生物组织、传感器、光伏等领域具有极好的应用前景。利用电流体动力打印技术可以实现对半导体材料油墨的精准分配和沉积。本论文以碘化铅、钙钛矿光探测器作为研究对象,通过探索不同EHD打印参数在ITO玻璃上制备碘化铅、钙钛矿薄膜的方法,分析器件的物理性质和电学性能,得到了高性能的碘化铅、钙钛矿光探测器,这为其在光芯片中的应用奠定了一定的研究基础。首先,采用EHD打印技术在导电玻璃衬底上制备碘化铅薄膜,通过不断调整打印参数,我们对在优化参数下制备的碘化铅薄膜进行了多方面的性能表征,发现用该参数打印的碘化铅薄膜比较致密,表面较为光滑均匀,且结晶性较好,为了进一步证实碘化铅薄膜的质量,我们制备了相应的碘化铅光探测器,并对其进行了详细的电学性能测量和分析。结果发现,通过电流体动力打印获得了性能优异的碘化铅光探测器,该器件具有非常好的开/关电流比为10~3,良好的光响应度为1.08m A/W,响应速度比较快,上升时间常数为45ms,衰减时间常数为49ms,且暗电流非常小,仅有1.68p A。其次,通过EHD打印技术,在原先的基础上,使用异丙醇作为溶剂的钾基碘化铵油墨在之前打印好的碘化铅薄膜衬底上继续第二步打印来制备有机/无机杂化钙钛矿薄膜,对打印过程进行了参数优化,我们发现用该方法印刷的钙钛矿薄膜表面平整,较为致密,为验证它的质量,我们制备了钙钛矿器件,并对其I-V特性、开关比、光谱灵敏度、外量子效率以及时间响应进行了详细的分析和说明。结果表明,钙钛矿光探测器性能优异,探测器具有极高的开/关电流比,高达10~3到10~4,良好的光响应度为6.67m A/W,响应速度非常快,上升时间常数为160us,衰减时间常数为2.8ms,暗电流仅有3.64p A。所有讨论的数据都揭示了EHD打印技术将为下一代光电子器件的制备提供新思路。更多还原

【Abstract】 Optoelectronic device which can change optical signal into electrical signal.As the core component of optical chip,its fabrication technology and performance will directly affect the output and quality of optical chip.It is an important research content of semiconductor photodetector to improve the performance of photodetector by optimizing the preparation process of thin films based on different light-absorbing materials.Since the birth of the first piece of perovskite solar cells in 2009,perovskite materials has been further discovered excellent photoelectric properties,including the light absorption coefficient of large,band gap is adjustable etc,as a core light absorption layer,it has a wide range of application in photodetectors,thin film transistors and other fields.As a typical perovskite derivative,lead iodide thin films can provide basic physical information for most applications due to their high density and high atomic number at room temperature,It is also a very promising semiconductor material for photodetectors.Electrohydrodynamic(EHD)Printing technology as a new 3D printing,because this way has the advantage of no mask,simple manipulation,high efficiency,good ink compatibility,high material utilization,can promote the polarity of crystallization and large areas of the preparation etc,It is widely applied to the biological tissue,sensors,solar cells and so on.Electrohydrodynamic printing technology can be used to achieve accurate distribution and deposition of semiconductor ink.This thesis take lead iodide and perovskite photodetector as the research object,through exploring different EHD printing parameters on the preparation of lead iodide and perovskite thin films on the ITO glass,and we analyzed the physical properties and electrical performance of the device,the high performance lead iodide and perovskite photodetector is obtained,which lays a certain research foundation for its application in optical chip.First of all,using the EHD printing technology in preparation of lead iodide film on conductive glass substrate,by constantly adjust the printing parameters,we characterized the lead iodide thin film’s performance under optimized parameters in many aspects,as a result,lead iodide film printed with the parameter is more dense,uniform surface more smooth,and crystalline is better,in order to further confirm the quality of lead iodide film,we prepared the corresponding lead iodide photodetector,and carried out a detailed measurement and analysis of its electrical properties.The results show that the excellent performance of lead iodide photodetector is obtained by electrohydrodynamic printing.The device has a very good on/off current ratio of10~3,good responsivity of 1.08m A/W,the response speed is relatively fast,the rise time constant is 45ms,the decay time constant is 49ms,and the dark current is very small,only 1.68p A.Second,by EHD printing technology,on the basis of the original,using isopropyl alcohol as the solvent of potassium base ammonium iodide in the previously printed ink lead iodide film substrate continue to the second step is to print to the preparation of organic/inorganic hybrid perovskite membrane,after parameter optimization,we found that the perovskite film printed by this method has smooth surface,relatively dense.In order to verify the quality of the perovskite film,we prepared the perovskite photodetector,and analyzed the perovskite device’s I-V characteristics,switching ratio,spectral sensitivity,external quantum efficiency and time response in detail.the results show that the perovskite photodetector has excellent performance,with a very high on/off current ratio of 10~3to 10~4,a good responsivity of 6.67m A/W,the response time is very fast,the rise time constant is160us,the decay time constant is 2.8ms,the dark current is only 3.64 p A.All the data discussed reveal that EHD printing technology will provide new ideas for the fabrication of the next generation of optoelectronic devices.更多还原