Plasma processing apparatus with post plasma gas injection
Plasma processing with post plasma gas injection is provided. In one example implementation, a plasma processing apparatus includes a plasma chamber. The apparatus includes a processing chamber separated from the plasma chamber. The processing chamber includes a substrate holder operable to support a workpiece. The apparatus includes a plasma source configured to generate a plasma in the plasma chamber. The apparatus includes a separation grid separating the plasma chamber from the processing chamber. The separation grid can be configured to filter one or more ions generated in the plasma and allow the passage of neutral particles from the plasma chamber to the processing chamber. The apparatus can include at least one gas port configured to inject a gas into neutral particles passing through the separation grid.
1. A method for processing a workpiece in a plasma strip tool, the method comprising:
dissociating one or more molecules into one or more ions and one or more neutral particles in a mixture using a plasma generated in a plasma chamber of a plasma processing apparatus;
filtering the one or more ions generated by the plasma in the mixture using a separation grid comprising a first grid plate and a second grid plate wherein the first grid plate and the second grid plate are disposed between the plasma chamber and a processing chamber of the plasma processing apparatus, the processing chamber being separated from the plasma chamber by the separation grid;
passing the one or more neutral particles generated in the plasma through first holes extending through the first grid plate and through second holes extending through the second grid plate of the separation grid, the first and second holes being separate from each other;
controlling energy of the neutral particles passing through the separation grid by injecting a cooling gas into the neutral particles passing through the separation grid into the processing chamber from a gas injection port located between the first grid plate and the second grid plate of the separation grid; and
exposing the workpiece to the neutral particles in the processing chamber.
2. The method of claim 1 , wherein the cooling gas is an inert gas.
3. The method of claim 1 , wherein injecting the cooling gas into the neutral particles comprises injecting a cooling gas into neutral particles at a first portion of the separation grid and injecting a cooling gas into neutral particles at a second portion of the separation grid.