【作者】 胡军；

【导师】 刘璐； 高亮；

【作者基本信息】 华中科技大学 ， 软件工程（专业学位）， 2023， 硕士

【摘要】 短波红外光具有对人眼无害、穿透能力强、抗干扰能力强等优点,短波红外探测器在军事和民用领域都有着十分广阔的应用。作为新一代红外光电材料的硫化铅胶体量子点因其能带连续可调以及溶液法制备、低温旋涂的工艺,展现了实现短波红外波段全覆盖成像、降低红外成像成本等替代传统硅基像元阵列的潜力。然而由于硫化铅胶体量子点对空气中的水氧极为敏感,长时间与水氧接触将导致探测器劣化严重,降低成像质量。因此基于硫化铅胶体量子点探测器的薄膜封装以解决其稳定性问题,对于推进其商业化应用具有非常重要的意义。同时对探测器基本性能测试目前主要通过手动扎针测试,操作繁琐、费时费力。基于此,本文的研究内容包括以下三个方面:首先研究了叠层封装薄膜中的单层Al₂O₃、Si N_x、聚甲基丙烯酸甲酯（PMMA）封装薄膜的特性。通过优化原子层沉积制备Al₂O₃薄膜时的脉冲时间和吹扫时间等工艺参数,将折射率提升至1.597,粗糙度仅为0.3 nm;通过优化等离子体增强化学气相沉积制备Si N_x薄膜时的射频功率和气体流量比,将折射率优化至1.815,粗糙度仅为1.06 nm;研究了PMMA材料对探测器的影响,证明PMMA是一种适合硫化铅胶体量子点的封装材料。其次基于以上研究设计了四种叠层的薄膜封装结构,分别对其性能进行表征,并应用于量子点探测器上进行高温高湿老化、放置老化和温度循环老化。结果表明,Si N_x/Al₂O₃/PMMA/Al₂O₃的封装性能相对最好,水蒸气透过率达4.17×10^-4 g/m²?day^-1,在90℃、60%RH（Relative Humidity）的高温高湿条件下存储老化48 h和-40～85℃条件下温度循环老化48 h后,探测器性能基本不变,在25℃、50%RH条件下放置老化600 h后,探测器的暗电流密度仅增加20%。最后基于Lab VIEW平台开发了对探测器数据测试的软件界面,制备了探测器的数据通信电路板,实现探测器与读出电路的互连。通过将操作平台与板级读出电路搭建成系统,实现了多个探测器的自动化测试功能。更多还原

【Abstract】 As short-wave infrared（SWIR）light has the advantages of safety for human eyes,strong penetration ability,strong anti-interference ability,the SWIR detectors have been widely used in the military and civilian fields.As one of the new generation of infrared photoelectric materials,the lead sulfide colloidal quantum dots（Pb S CQDs）have shown the full coverage imaging of SWIR bands,the potential of reducing infrared imaging costs and replacing traditional silicon-based pixel array because of their continuously tunable bandgap,solution processing and low temperature spin coating process.However,since Pb S CQDs are extremely sensitive to water vapor and oxygen in the air,long-term contact with water vapor and oxygen would lead to serious deterioration of the CQDs detector and reduced imaging quality.Therefore,the thin film encapsulation based on Pb S CQDs detectors to solve its stability problem is of great significance for promoting their commercial application.At the same time,the basic performance is mainly tested by manual tie-piercing,which is tedious and time-consuming.Based on this,the research content of this article includes the following three aspects:Firstly,the characteristics of single layer encapsulation of Al₂O₃,Si N_x and polymethyl methacrylate（PMMA）thin film has been investigated used in the layer laminated encapsulation film.By optimizing the atomic layer deposition parameters such as pulse time and purge time,the refractive index of prepared Al₂O₃ thin film was increased to 1.597 and the roughness of only 0.3nm.By optimizing the RF power and gas flow ratio of plasma enhanced chemical vapor deposition,the refractive index of prepared Si N_x film was optimized to 1.815 and the roughness of only 1.06 nm.The influence of PMMA material was also investigated on Pb S CQDs detectors,proving that PMMA was a suitable encapsulation material for Pb S CQDs.Then,based on the above researches,four kinds of laminated film encapsulation structures were designed to characterize their properties.They were then applied to CQDs detectors for high temperature and humidity aging,storage aging and temperature cycle aging to investigate their encapsulation performance.The results showed that the encapsulation performance of Si N_x/Al₂O₃/PMMA/Al₂O₃ is relatively the best with the Water Vapor Trausmission Rate of only 4.17×10^-4 g/m²?day^-1.The performance of the CQDs detector was basically unchanged during the aging process at 90℃and 60%RH（Relative humidity）for 48 h and temperature cycle aging at-40～85℃.The dark current density of the CQDs detector increased by only 20%after the storage aging at 25℃and 50%RH for 600 h.Finally,the software interface of detector data testing was developed based on Lab VIEW platform.The data communication circuit board of the detector was prepared to realize the connection of detector and readout circuit.By combining the operating platform with the board readout circuit,the automatic testing function of multiple detectors was realized.更多还原