USC MEMS group (http://mems.usc.edu) has post doctor    openings in

1. Aacoustic tweezers
2.  Transducer technology based on bulk acoustic waves for cell sorting and manipulation in microfluidic systems
3.  Electromagnetic vibration-energy harvesters.

If you are interested in above field, please send an email to Prof. E.S. Kim (eskim@usc.edu).