Study On The Package Design Of An Uncooled Infrared Focal Plane Array Detector Without Pumping Nozzle

Packaging design of uncooled infrared focal plane detector in the life of vacuum device and meeting the requiretments of devices of optical and mechanical and thermal have important value in prospective application. Because the detector encapsulation research greatly lags behind that of the chip in both at home and abroad at present, the packaging technology and designing work stalled which prevented many chips into practical application.First of all, this dissertation introduces the chip of uncooled infrared detector, which illustrate the necessity work of probe vacuum packaging and design. After analyze the deficiency of the existing detector, this dissertation proposed detector without pumping nozzle ceramic packing style. Also this dissertation introduces the basis and process of probe general packaging design.General requirements, binding the claim of force and heat and electricity, of packaging design of detector without pumping nozzle have been proposed to determine the raw materials or components of target detector. Under the requirements of the assembly design principles, using SolidWorks software to design reasonable structure and COMSOL Multiphysics software to carry on the simulation, specific target detector assembly style is given. By analyzing intensity of the infrared window which the getter is integrated, window thickness range value and bonding strength is given. Through the analysis of the resistance strength of the internal parts of components, welding or bonding strength requirements are given. The heat transfer mode of target detector has been simplified, and suitable semiconductor refrigerating machinery worked for stable working temperature of chips chosen. Describing the demand of vacuum environment when the target detector was working, and putting forward a tiny vacuum gauge was placed to real-time monitoring the vacuum values change inside device. In order to maintain the vacuum environment, evapotranspiration getter is applied in the target detector and getter suction principles are presented in detail.The encapsulation processes of the above target detector are designed in detail, including SMT process and integration of exhaust and activation and encapsulation process. This dissertation selects 3500-bender machine to achieve high precision SMT process requirements of target detector, and give detailed implementation process. In dissertation, a dedicated exhaust station is used, which can realize the leak detection, baking exhaust and partition at the same time. The liquid getter is chosen, which is integrated with infrared window, to narrow occupied volume and enlarge suction surface area. The getter is activated in an isolated environment, which activation temperature and time need to be strictly controlled while operation. This dissertation selects the soldering material containing indium metal which can meet special requirements of low temperature process of target detector.