Microwave preclean apparatus and processing method for impurity removal

A method of processing a semiconductor structure formed in a substrate, comprising:

• exposing a feature formed within a substrate to a preclean process, wherein the preclean process comprises:
• positioning a substrate within a processing chamber that comprises a microwave source;
• flowing a process gas that comprising hydrogen into the processing chamber;
• delivering microwave energy, from the microwave source, to the processing gas, wherein delivering the microwave energy to the process gas does not generate a plasma in the processing chamber;
• and
• maintaining the substrate at a temperature below 300° C.

A microwave processing tool comprising:

• a chamber;
• a chuck disposed in the chamber;
• an array of modular high-frequency emission modules coupled to the chamber;
• and
• a controller configured to cause the microwave processing tool to:
• position a substrate within a processing chamber that comprises a microwave source;
• flow a process gas that comprising hydrogen into the processing chamber;
• deliver microwave energy to the processing gas, wherein delivering the microwave energy to the process gas does not generate a plasma in the processing chamber.