This is a multi-part message in MIME format. --------------CEF0B4AA18D423A84A059DB3 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Hello Mario, Although you mentioned you want an isotropic etchant, for fast wafer thinning purposes it is easy to use either KOH or TMAH solutions. Results show that the surface polishing is hardly affected if you want to etch only 50 um on each side. KOH is faster but I think that TMAH yields better smoothness. I hope this is helpful. Eran Socher Dept. EE, Technion - Israel Institute of Technology Haifa 32000, Israel Mario Adamschik wrote: > Question for Discussion group: > > Subject: Isotropic Si etching with high etching rate > > I am searching for a etchant for high rate isotropic > Si etching. > I want to thin a 200 micron wafer to 100 micron. > > Thank to all in advance > Mario > >