Study on Porous Silicon as a Sacrificial Layer in Microsensor

The porous silicon was successfully prepared by double-cell electrochemical etching.The SEM photos of porous silicon shows that the porous silicon obtained by this method has the smallest hole diameter,good uniformity,large depth(exceeding 100 μm),and removal porous silicon using the mighty watery KOH solution.The above porous silicon much more accords with the appliance require of sacrificial layer in MEMS.Finally,the etching time and current of double-cell electrochemical etching which affect the etching speed of the porous silicon were studied.