Patent ID: 7938911

Claim:
A process for cleaning a semiconductor wafer in an individual-wafer treatment using a cleaning solution, comprising: contacting the semiconductor wafer with a first cleaning solution comprising an alkaline ammonium component, the first solution being free of HF, ozone, and hydrogen peroxide; adding at least HF to the first cleaning solution incrementally or continuously to form a further cleaning solution, such that the HF concentration in the further cleaning solution is increased with respect to the HF concentration present upon an initial introduction of HF to the first cleaning solution, the cleaning solution remaining free of ozone and hydrogen peroxide wherein a molar concentration ratio of hydrogen fluoride to alkaline ammonium component, HF:NR 4 OH, of <1 initially present in the further cleaning solution is increased to >1 at the end of cleaning, wherein R independently represents H, methyl, ethyl, propyl or butyl radicals.