Hello Lin, You can get these from Virginia Semiconductor Inc at (540) 373-2900 in Frederickburg Virginia. They also have substrates as thin as 5 um. Ask for Perry or Liz. Good Luck, Stephen Jones University of Virginia EE dept. >> >> I'd like to get some 3", N(100), resistivity>5 Ohm-cm, 200um thick wafers. >> Does anybody know where I can get them? Besides, I want to etch polyimide >> film the wafer, does anybody know the etchant for the polyimde wet etching? >> Any reply will be appreciated. Thanks in advance, >> Best regards, >> >> Lin >> >> ************************************************** >> Lin Wang, Graduate Student >> Department of Electrical and Computer Engineering >> Beckman Institute, Rm B428C >> University of Illinois at Urbana-Champaign >> 405 North Mathews Avenue >> Urbana, IL 61801 >> >> e-mail: lwang@uibrl.brl.uiuc.edu, linwang1@uiuc.edu >> Tel. (217)-333-1088(O), (217)-351-8976(R) >> ************************************************** >> >> >> >>