Method and apparatus for plasma dicing a semi-conductor wafer
View Patent ↗The present invention provides a method for plasma dicing a substrate. The method comprising providing a process chamber having a wall; providing a plasma source adjacent to the wall of the process chamber; providing a work piece support within the process chamber; placing the substrate onto a support film on a frame to form a work piece work piece; loading the work piece onto the work piece support; providing a cover ring disposed above the work piece; generating a plasma through the plasma source; and etching the work piece through the generated plasma.
1. A method for plasma dicing a substrate, the method comprising:
placing the substrate on a tape on a frame to form a work piece, wherein the substrate comprises at least one device having aluminum contacts, the at least one device is formed on a front side of the substrate and a back side of the substrate is attached to the tape, the front side of the substrate having dicing streets patterned in a masking material;
placing the work piece into a plasma processing chamber;
exposing the at least one device on the substrate in the plasma processing chamber to a first time division multiplexed etch process until a substrate/tape interface is exposed within the dicing streets, wherein the first time division multiplexed etch process comprises a fluorine based etch chemistry and unwanted AlF 3 residues are formed on the at least one device on the substrate during the etch process;
detecting the exposed substrate/tape interface by optically monitoring plasma emission;
terminating the first time division multiplexed etch process based on the detecting the exposed substrate/tape interface;
exposing the at least one device on the substrate in the plasma processing chamber to a second hydrogen based plasma process to remove the unwanted AlF 3 residues from the at least one device on the substrate, said exposure of the at least one device on the substrate to the second hydrogen based plasma process occurring after the termination of the first time division multiplexed etch process.
2. The method according to claim 1 wherein the second hydrogen based plasma process is initiated without breaking vacuum from the termination of the first time division multiplexed etch process.
3. The method according to claim 1 , wherein the unwanted AlF 3 residues are removed from the at least one device on the substrate using the second hydrogen based plasma process, said removal of unwanted AlF 3 residues from the at least one device on the substrate on the work piece occurring after singulation of the substrate on the work piece.