Research on VO_x uncooled infrared bolometer based on porous silicon

Abstract

In this paper, vanadium oxide thin film of TCR of -3.5%/K has been deposited by pulsed DC magnetron sputtering method. The property of this VO_x has been investigated by X-ray diffractometer (XRD) and atomic force microscopy (AFM) in detail. XRD test indicates that this film is composed of V₂O₃, V₃O₅ and VO₂.VO_x microbolometer with infrared (IR) absorbing structure is fabricated based on porous silicon sacrificial layer technology. Optimized micro-bridge structure is designed and carried out to decrease thermal conductance and this structure shows good compatibility with micromachining technology. This kind of bolometer with 74% IR absorption of 8–14 μm, has maximum detectivity of 1.09×10⁹ cm·Hz^1/2/W at 24 Hz frequency and 9.8 μA bias current.

Keywords

infrared (IR) / porous silicon / microbolometer / micromachining

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Acknowledgements

This work was supported by the National Natural Science Foundation of China (Grant No. 61077078).

RIGHTS & PERMISSIONS

2014 Higher Education Press and Springer-Verlag Berlin Heidelberg