Sensor Prep Services, in Elburn Illinois, provides a good quality 7740 substrate. Contact them at (630) 365-9645 or email sensors@earthlink.net. Specialty Glass also can provide glass substrates. They're in Willow Grove, PA at (215) 659-8400 Good luck! -Rich Rich Hjulstrom Siemens-Moore Spring House, PA 19477 -----Original Message----- From: Lyle Leverich [mailto:lleverich@ghz.com] Sent: Tuesday, February 22, 2000 6:20 PM To: MEMS@ISI.EDU Subject: 3" 7740 Glass Does anyone know a source for 3" 7740 or "Borofloat" wafers ?