Patent ID: 7341065

Claim:
A method comprising: dispensing a first liquid having a pH above approximately 9 onto a topside of a horizontally spinning 300 mm wafer from a first single dispense approximately centered over the wafer; maintaining a combination of a first wafer spin rate and first liquid flow rate that is above a curve defined by the combinations of approximate wafer spin rates and approximate liquid flow rates of 2000 rpm and 1.25 l/min, 1000 rpm and 2.2 l/min, and 200 rpm and 3.4 l/min; dispensing a second liquid having a pH at least approximately 2 points below the first liquid pH onto the topside of the horizontally spinning 300 mm wafer from a second single dispense approximately centered over the wafer; ceasing the dispensing of the first liquid; and maintaining a combination of a second wafer spin rate and second liquid flow rate that is above the curve.