Remote plasma activation is presented here as a surface technique allowing hydrophilic wafer bonding at elevated temperatures. Prebonding remote plasma treatment resulted in a marked improvement over other techniques, increasing bonding energy for both the initial van der Waals bond and the final covalent bond. Increased bonding energy is reported over a variety of bonding and annealing conditions. Bond energies of 2.4 J/m(2) were attained for Si-Si pairs annealed at 275 degrees C. Increased bonding energy enabled elevated-temperature (180 degrees C) Si-quartz bonding. Results focus on plasma parameter variations of exposure time and gas species and the effect on surface energy. (c) 2007 The Electrochemical Society.