Much of the exposure energy comes from surface reflections. If the copper has a much higher reflection than the NiFe at the relevant wavelengths (usually 365 -435nm) you will see this. Shay -----Original Message----- From: mems-talk-bounces+shay=mizur.com@memsnet.org [mailto:mems-talk-bounces+shay=mizur.com@memsnet.org] On Behalf Of Ricky Anthony Sent: Thursday, October 17, 2013 8:11 PM To: mems-talk@memsnet.org Subject: [mems-talk] Resist Development dependence on Substrate Coat Hi All, I have recently trying to develop a resist for equal thickness on two different substrates (NIfE AND Cu coated). Even though the same process has been used for both, the development time for NiFe is two times higher than that with Cu. Any reasons? Many Thanks, Ricky Anthony Phd Student Microsystems Center Tyndall National Institute University College Cork Cork, IRELAND _______________________________________________ Hosted by the MEMS and Nanotechnology Exchange, the country's leading provider of MEMS and Nanotechnology design and fabrication services. Visit us at http://www.mems-exchange.org Want to advertise to this community? See http://www.memsnet.org To unsubscribe: http://mail.mems-exchange.org/mailman/listinfo/mems-talk _______________________________________________ Hosted by the MEMS and Nanotechnology Exchange, the country's leading provider of MEMS and Nanotechnology design and fabrication services. Visit us at http://www.mems-exchange.org Want to advertise to this community? See http://www.memsnet.org To unsubscribe: http://mail.mems-exchange.org/mailman/listinfo/mems-talk