| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide technology which can satisfactorily remove foreign matter stuck to a substrate (e.g., particles and residues at etching time) by dry cleaning. <P>SOLUTION: A silicon oxide film 8 formed on the surface of a wafer W by oxidation at ashing time is etched by hydrogen fluoride gas to remove particles P stuck to the wafer W together with the silicon oxide film 8. At the time of etching by hydrogen fluoride, the wafer W is set with its surface down, and further the wafer W is heated to be electrically charged, whereby heat migration and electrostatic forces, in addition to gravity, are made to act upon particles P. Also, after the silicon oxide film 8 is etched at ashing time, the surface of the wafer W is further oxidized by, for example, ozone gas and then etched by hydrogen fluoride gas. These successive steps are carried out once or twice or more, making it possible to remove the particles P more surely than ever. <P>COPYRIGHT: (C)2012,JPO&INPIT |
