| abstract |
(57) [Summary]nA method for removing carbon-containing contaminants and other substances from a wafer surface. The method can be performed to minimize loss of the desired film on the wafer surface. The method is performed in a sealed reaction vessel. A gas mixture comprising oxygen and fluorine containing gases is flowed over the wafer during simultaneous exposure to ultraviolet radiation. This gas mixture does not contain additional water, hydrogen, hydrogen fluoride or hydrogen-containing organics, so that the formation of water as a reaction product is avoided. At high oxygen concentrations, for example, greater than 92% by volume of the mixture of fluorine containing gas and oxygen, silicon is hardly etched and a thin passivation layer is formed which suppresses hydrocarbon recontamination. |