After oxide hard mask etching and strip/clean, the silicon wafer surface retains adsorbed moisture, chemical residues, and potentially volatile organics P2.The Vacuum Bake step operates immediately prior to Rapid Thermal Processing (RTP) and Aluminum Oxide (AlO) high-k dielectric deposition P3.In a 40nm Backside Illuminated (BSI) CMOS Image Sensor, the backside silicon surface must achieve extremely low surface recombination velocities to minimize dark current and white pixel defects P1.By execu