High-pressure processing chamber for a semiconductor wafer

1. An apparatus for processing a semiconductor wafer, comprising:

a. an upper element;

b. a lower element, wherein the upper element and the lower element are configured to be brought together to form a processing volume;

c. a seal energizer that comprises a seal-energizing cavity coupled to the upper element and configured to maintain the upper element against the lower element by a sealing pressure generated within the seal-energizing cavity; and

d. a pressure controller configured to automatically non-linearly vary the sealing pressure to lag a processing pressure generated within the processing volume and maintain the processing volume during processing.

2. The apparatus of claim 1 , wherein the seal energizer is configured to apply a non-negative net force against one of the upper element and the lower element above a threshold value, the net force following the equation P 2 *A 2 −P 1 *A 1 , wherein P 2 equals the sealing pressure, P 1 equals a pressure generated within the processing volume, A 2 equals a cross-sectional area of the seal-energizing cavity, and A 1 equals a cross-sectional area of the processing volume.

3. The apparatus of claim 2 , wherein the cross-sectional area A 2 is larger than the cross-sectional area A 1 .

4. The apparatus of claim 1 , wherein the seal energizer further comprises a first cavity, wherein the first cavity is coupled to the seal-energizing cavity, and the seal energizer is configured so that a first pressure generated within the first cavity generates a second pressure in the seal-energizing cavity larger than the first pressure.

5. The apparatus of claim 1 , further comprising a means for generating supercritical conditions coupled to the processing volume.

6. The apparatus of claim 5 , further comprising a CO 2 supply vessel coupled to the processing volume.

7. The apparatus of claim 1 , wherein the upper element and the lower element form a supercritical processing chamber.

8. The apparatus of claim 1 , wherein the seal energizer comprises a hydraulic piston coupled to the lower element and configured to maintain the processing volume.

9. The apparatus of claim 1 , wherein the pressure controller is programmed to maintain a difference between a sealing force and a force generated within the processing volume within a preselected range.

10. The apparatus of claim 9 , wherein a lower bound of the preselected range includes a minimum force for maintaining the processing volume.

11. The apparatus of claim 10 , wherein the minimum force is based on a delay between generating the sealing force and generating the force within the processing volume.

12. The apparatus of claim 1 , wherein the force generated within the processing volume varies during a processing cycle.

13. The apparatus of claim 1 , wherein the pressure controller comprises a pressure regulator.

14. The apparatus of claim 13 , further comprising a pressure monitor coupled to the processing volume and to the pressure regulator.

15. An apparatus for processing a semiconductor wafer, comprising:

a. an upper element;

b. a lower element coupled to a seal-energizing cavity, wherein the upper element and the lower element are configured to be brought together to form a processing volume; and

c. means for automatically non-linearly varying a sealing pressure within the seal-energizing cavity to maintain within a preselected range a difference between a sealing force and a force generated within the processing volume, thereby maintaining the processing volume.

16. An apparatus for processing a semiconductor wafer, comprising:

a. a processing chamber comprising a processing volume for processing the semiconductor wafer by generating a processing pressure; and

b. means for maintaining the processing volume by sensing the processing pressure during processing and automatically generating a sealing pressure that non-linearly lags the sensed processing pressure.