Micromachining porous silicon thin films for thermal sensing applications

This work reports a novel CMOS-compatible micromachining process to fabricate large porous silicon membranes which are electrically isolated from the silicon substrate. The process developed successfully addresses the challenges of photoresist seepage into pores and the instability of the films in alkaline developers. These fabricated membranes can be potentially used as a temperature sensing membrane in uncooled thermal detectors operating in long wavelength infrared region (LWIR).