Design Of Micromechanical Thermopile Infrared Detector That Compatible With CMOS Process

At present, infrared technology, whose one of the core components is the infrareddetector, is widely used in both military and civil domain. The thermopile infrared detector isa kind of thermal infrared detector that developed earlier. For the advantages of working atroom temperature, wider response spectrum of infrared radiation, and lower production costs,the thermopile infrared detector is developed rapidly and applied widely. Since theMicro-Electro-Mechanical Systems(MEMS) was developed, the micromechanical thermopileinfrared detector that based on MEMS technology became the popular research quickly byvirtue of multiple strengths. However, the progress of thermopile infrared detector onpractical application is still slow because of the difficulty of preparation technology. Thepaper aiming at researching the thermopile infrared detector, provides a new structure ofmicromechanical thermopile infrared detector whose manufacture technology is compatiblewith CMOS and performances(such as higher voltage-responsivity, lower noise equivalenttemperature difference and so on). On the basis of the structure, a series of productionprocesses which are simple and feasible are obtained.For the purpose of improving the infrared absorption and responsivity in the thesis, theresonant cavity is introduced into the design, in addition to the suitable materials are selectedto match the thermocouple and the absorbing layer.The noise of the device is reduced by thedecrease of thermopiles while the responsivity is not affected. By the simulation software, thesize of the device is optimized and simple finite element simulation is done. The optimizedperformance parameters, as the theoretical foundation of following preparation technology,are calculated. In the design, the device which all structures are composed of the material commonlyused in the CMOS, is manufactured by the production method that is fully compatible with ICtechnology. In order to improve the success rate of detector production, some severalindividual key technology, including isolation trench etching and filling, isolation trenchplanarization, minimum line lithography of metal connected, are experienced when thepreparation technology experiments are done.Eventually, a series of complete, simplemanufacture and high feasibility process flow is obtained, through integration andoptimization.