Method for minimizing contamination in semiconductor processing chamber
View Patent ↗A semiconductor processing apparatus includes a reaction chamber, a loading chamber, a movable support, a drive mechanism, and a control system. The reaction chamber includes a baseplate. The baseplate includes an opening. The movable support is configured to hold a workpiece. The drive mechanism is configured to move a workpiece held on the support towards the opening of the baseplate into a processing position. The control system is configured to create a positive pressure gradient between the reaction chamber and the loading chamber while the workpiece support is in motion. Purge gases flow from the reaction chamber into the loading chamber while the workpiece support is in motion. The control system is configured to create a negative pressure gradient between the reaction chamber and the loading chamber while the workpiece is being processed. Purge gases can flow from the loading chamber into the reaction chamber while the workpiece support is in the processing position, unless the reaction chamber is sealed from the loading chamber in the processing position.
1. A method of processing a semiconductor workpiece in a semiconductor processing apparatus comprising a cross-flow reaction chamber located above a loading chamber, separated by a baseplate including an opening, the method comprising:
loading a semiconductor workpiece onto a moveable workpiece support when the support is in a loading position;
moving the workpiece support between the loading position and a processing position;
maintaining a higher pressure in the cross-flow reaction chamber than in the loading chamber while the workpiece support is moving;
processing the workpiece after the workpiece support is moved to the processing position, wherein processing comprises flowing a reaction gas approximately parallel to a face of the workpiece; and
maintaining a lower pressure in the reaction chamber than in the loading chamber during processing.
2. The method of claim 1 , further comprising:
flowing a purge gas into the reaction chamber while the workpiece support is moving; and
pumping gas out of the loading chamber while the workpiece support is moving.
3. The method of claim 2 , further comprising:
flowing purge gas into the loading chamber during processing; and
pumping gas out of the reaction chamber during processing.
4. The method of claim 3 , further comprising:
moving the workpiece support from the processing position to the loading position after processing.
5. The method of claim 1 , wherein the workpiece support engages the baseplate opening when the workpiece support is in the processing position.
6. The method of claim 5 , wherein engaging comprises maintaining a gap between the baseplate and the workpiece support.
7. The method of claim 5 , wherein engaging comprises creating a seal between the baseplate and the workpiece support.
8. A method of processing a workpiece in a semiconductor processing apparatus comprising a cross-flow reaction chamber located above a loading chamber, separated by a baseplate including an opening, the method comprising:
loading a semiconductor workpiece onto a moveable workpiece support when the support is in a loading position;
moving the workpiece support between the loading position and a processing position;
flowing gas from the reaction chamber into the loading chamber while the workpiece support is moving;
flowing gas from the loading chamber into the reaction chamber when the workpiece support is in the processing position; and
processing the workpiece after the workpiece support is moved to the processing position, wherein processing comprises flowing as approximately parallel to a face of the workpiece.
9. The method of claim 8 , further comprising:
flowing a purge gas into the reaction chamber while the workpiece support is moving; and
pumping gas from the loading chamber while the workpiece support is moving.
10. The method of claim 8 , further comprising:
flowing a purge gas into the loading chamber while the workpiece support is in the processing position; and
pumping gas from the reaction chamber while the workpiece support is in the processing position.