Method for widening the laser planarization process window for metalized films on semiconductor wafers

Abstract

The invention relates to taking advantage of increasing the boiling point of a material by increasing pressure within the processing chamber, which will then push the optical ablation limit to a higher optical fluence (laser intensity). A method in accordance with the invention of planarizing a metallic film on a semiconductor wafer employing laser energy comprises: a) injecting an inert gas into a laser planarization chamber to provide a desired pressure within the chamber which is above 1 Torr; and b) selectively applying laser energy to the metallic film within the chamber containing the inert gas and maintained at a pressure greater than 1 Torr. Increasing pressure within the chamber in this manner will raise the boiling temperature of the particular metallic film without a corresponding significant increase in the melting temperature of the metallic film.

Dependencies are inferred from the claim text.