Variable seal pressure slit valve doors for semiconductor manufacturing equipment

1. A method for sealing an opening between two chambers in a semiconductor processing device, the method comprising:

providing a first chamber;

providing a second chamber;

providing a wall separating the first chamber from the second chamber, the opening extending circumferentially along an exterior surface of the wall;

providing a slit door having an o-ring mounted along edges of the slit door, the slit door configured to move in a direction generally parallel to the exterior surface of the wall between an open position and a closed position, the opening allowing communication between the first chamber and the second chamber when the slit door is in the open position, and the opening being sealed when the slit door is in the closed position;

moving the slit door from the open position to the closed position using an actuator;

applying a first pressure to the slit door in the closed position using the actuator, the first pressure applied by the actuator in the direction generally parallel to the exterior surface of the wall; and

applying a second pressure to the slit door in the closed position using the actuator, the second pressure applied by the actuator in the direction generally parallel to the exterior surface of the wall, wherein the first pressure is different than the second pressure, and the first pressure and the second pressure depend on a pressure gradient between the first chamber and the second chamber.

2. The method of claim 1 further comprising measuring a pressure inside the first chamber, the first pressure being based on the pressure.

3. The method of claim 1 further comprising calculating the pressure gradient based on pressure measurements taken inside the first chamber and inside the second chamber.

4. A method for sealing an opening between two regions in a semiconductor processing device, the method comprising:

providing a first region;

providing a second region;

providing a wall separating the first region from the second region, the opening extending circumferentially along an exterior surface of the wall;

providing a slit door having an o-ring mounted along an edge of the slit door, the slit door configured to seal the opening when in a closed position;

positioning the slit door in the closed position;

applying a first sealing pressure on the slit door in the closed position using an actuator, the first sealing pressure applied in a direction generally parallel to the exterior surface of the wall; thereafter

forming a film on a substrate positioned in the first region;

applying a second sealing pressure on the slit door in the closed position using the actuator, the second sealing pressure applied in the direction generally parallel to the exterior surface of the wall; and thereafter

cleaning the first region;

wherein the first sealing pressure is greater than the second sealing pressure.

5. The method of claim 4 wherein the first sealing pressure greater than the second sealing pressure by at least 25 psi.

6. The method of claim 4 further comprising measuring a pressure of the first region during cleaning, the second sealing pressure being based on the pressure.

7. The method of claim 4 wherein the applying the first sealing pressure and applying the second sealing pressure is automatically implemented by control logic.

8. The method of claim 1 wherein the o-ring surrounds a circumference of the opening when the slit door is in the closed position.

9. The method of claim 1 wherein the actuator is a pneumatic actuator.

10. The method of claim 1 further comprising detecting cleaning chemicals inside the first chamber, the second pressure being based on detection of the cleaning chemicals.

11. The method of claim 4 further comprising measuring a pressure of the first region during film formation, the first sealing pressure being based on the pressure.

12. The method of claim 4 further comprising measuring a pressure of the second region during film formation, the first sealing pressure being based on the pressure.

13. The method of claim 4 further comprising measuring a pressure of the second region during cleaning, the second sealing pressure being based on the pressure.

14. The method of claim 4 further comprising detecting cleaning chemicals inside the first region during cleaning, the second sealing pressure being based on detection of the cleaning chemicals.