abstract |
A downstream ashing apparatus for removing organic resist from a silicon semiconductor wafer. The apparatus includes a waveguide leading to a microwave cavity. A plasma generating chamber is a part of the cavity, which also includes a quartz plate that is transparent to the microwaves. A device feeds oxygen gas and water vapor to the plasma generating chamber. A plasma is generated by the microwaves from the gas mixture in the plasma generating chamber. On a wall opposite the quartz plate, a plurality of holes is provided which connects the plasma generating chamber to a reaction chamber. Only a reactive species, such as oxygen atoms, generated in the plasma, flows from the plasma generating chamber through the holes and into the reaction chamber. The microwaves do not pass into the reaction chamber. The reactive species chemically reacts with and removes the resist on the semiconductor wafer in the reaction chamber. |