Manufacture And Characterization Of MEMS Infrared Sources With High Electro-Optic Convert Efficiency

As the key components of infrared instruments, infrared sources have the characteristicsof long-distance, better anti-jamming perfoemance, high spatial resolution, and the capabilityof working at all time and under all-weather conditions. They have important applicationvalue in the fields of air quality monitoring, personnel search and rescue, aircraft landingguidance, infrared communication and so on. In order to meet the trends of miniaturzation andlow-cost infrared instruments, the MEMS infrared sources with excellent perfoemance andsmall size are manufactured in microscale. It has become the hot spot of the world at thisstage in the field of infrared technology.Materials regulation, structure design, simulation and manufacturing methods of MEMSinfrared sources with electro-optic convert efficiency were systematically studied in detail.The manufacturing process was based on silicon on insulator（SOI）substrate, using LPCVDtechnology to grow polysilicon. The emitting layer about resistance heating and bodyradiation effects were achieved through boron diffusion in single cryatal silicon and ionimplantation in polysilicon. The electrical-thermal coupled simulation analysis about radiationlayer was analysed by ANSYS software. The suspended film structure was fabricated throughetching silicon substrate using DRIE technology. And the thermal damage accumulationleaded by heat capacity of the radiator body could be reduced obviously. The integratedmanufacture of MEMS infrared sources with high electro-optic convert efficiency wascomplemented after electrical interconnection of the source was realized by sputteringaluminum.The characteristics of MEMS infrared source which had been manufactured was testing.The I-V curve assumed fine linear relation, and resistance was about50. The surfacetemperature of the MEMS infrared source was measured under different diving voltage. And the surface temperature was about750K when the diving voltage was5.8V. The testing resultsof relative radiation spectrum showed that infrared spectral bands of the source was mainlydistributed in the3~5μm, and the center wavelength was3.6μm. The radiation intensity ofMEMS infrared source was measured with different testing distance and angles. Theexperimental results showed that the radiation intensity decreased rapidly in the range of0to50mm, and gradually stabilized after50mm. The radiation spectrum of the infrared sourcecovered from-30degree to30degree under the driving voltage was5.8V. The radiationintensity was highest at collimation direction, and the electro-optic convert efficiency was upto20%.