Hello, Fusion bonding should work well. First prebond the well cleaned wafers (nitric acid and KOH cleaning) at room temperature by appliying slight pressure If prebond is okay, put in a furnace for several hours (400 - 650 C ) -- Anil Agiral PhD student MESA+ Institute for Nanotechnology, University of Twente Faculteit Elektrotechniek, Wiskunde en Informatica BIOS, the Lab-on-a-Chip Group