Plasma process for removing excess molding material from a substrate

A method for removing two-component molding material from an area on a substrate placed within a treatment chamber, the two component molding material containing an organic matrix and a plurality of silica particles dispersed in the organic matrix, the method comprising:

• placing the substrate within the treatment chamber;
• introducing a first gas mixture containing less than 50 percent by volume of a fluorine-containing gas species and an oxygen-containing gas species into the treatment chamber at an operating pressure in the range of about 800 mTorr to about 2500 mTorr;
• forming a plasma in the treatment chamber from the first gas mixture;
• exposing the substrate to the plasma generated from the first gas mixture to remove the organic matrix from the area and leave the plurality of silica particles;
• without removing the substrate from the treatment chamber and without extinguishing the plasma in the treatment chamber, changing from the first gas mixture to a second gas mixture containing more than 50 percent by volume of the fluorine-containing gas species and the oxygen-containing gas species at an operating pressure in the range of about 800 mTorr to about 2500 mTorr;
• forming a plasma in the treatment chamber from the second gas mixture;
• and
• exposing the substrate to the plasma generated from the second gas mixture to remove the plurality of silica particles from the area.