Dear Gamze, I was told that you are looking for silicon microphones. I am working on an ultra miniature (particle velocity) microphone: The Microflown. if you want more information please look on our Internet side. If you have specific questions please ask HELIAS -------------------------------------------------- ir. Hans-Elias de Bree Graio at University of Twente A Proud member of the microflown team telephone at home +31 (0) 53 4323276 and at second home +31 (0) 20 4211233 on by bike +31 (0) 65 2667290 telephone at university +31 (0) 53 4894438 Fax at university +31 (0) 53 4893343 E-mail H.E.DeBree@el.utwente.nl Look at our WWW-page: http://www.el.utwente.nl/tdm/mmd/projects/muflown/muflown.html