Patent ID: 6860277

Claim:
A single type of semiconductor wafer cleaning apparatus comprising: a rotary wafer chuck on which a wafer is to be mounted and rotated; a gas spraying unit disposed above said wafer chuck, said gas spraying unit including a gas injection tube oriented to inject gas towards a wafer mounted to the chuck, and a gas guard connected to the gas injection tube, said gas guard defining a chamber having an open bottom adjacent the rotary chuck; de-ionized water supply means for supplying de-ionized water onto a wafer at a location outside said chamber when the wafer is mounted to the chuck, to thereby provide a layer of de-ionized water on the wafer; and gas supply means for supplying gases to the gas injection tube such that the gases issue from the tube and are confined by said chamber to thereby reduce the thickness of the layer of de-ionized water provided by the de-ionized water supply means on the wafer, whereby dissolving of the gases into the layer of water is facilitated on the wafer.