Modification of silicon surfaces with H2SO4:H2O2:HF and HNO3:HF for wafer bonding applications

Two combinations of oxidizing and etching agents, H2SO4:H2O2:HF and HNO3:HF, have been used to modify silicon surfaces prior to wafer bonding. The chemical oxide thickness can be adjusted between 0 and 10 Angstrom by tuning the HF content of the mixtures