Patent ID: 7585144

Claim:
A variable lot size load port assembly comprising: a tool interface extending generally in a vertical dimension, the tool interface having a front surface facing a front of the tool interface, a back surface generally parallel to the front surface, and an aperture; a port door having a closed position wherein the port door at least partially occludes the aperture and an open position wherein the aperture is substantially unobstructed by the port door; a latch key extending from the port door, the latch key being configured to mate with a latch key receptacle of a door of a front opening unified pod (FOUP); an advance plate positioned to the front of the tool interface below the aperture, the advance plate extending generally horizontally, and being configured to support a front opening unified pod (FOUP) and translate between a retracted position and an advanced position, the advanced position being proximate the tool interface and the retracted position being spaced from the tool interface; an elevator for raising and lowering the advance plate, the elevator being configured to bring the latch key receptacle of the door of the FOUP into alignment with the latch key of the port door, wherein a plurality of FOUPs of varying capacities, each having a latch key receptacle at a different elevation can be accommodated by the variable lot size load port assembly by varying an elevation of the advance plate; an upper seal plate having an upper end secured to the tool interface and a lower end covering a portion of the aperture, the upper seal plate being shaped to form a proximity seal with a front flange of the FOUP; and a lower seal plate having a lower end secured to the tool interface and an upper end covering a portion of the aperture, the lower seal plate being shaped to provide a proximity seal with the front flange of the FOUP, wherein, the tool interface includes a continuous recessed shoulder extending around the aperture; the upper seal plate is mounted to the recessed shoulder, extends down, and terminates just above a top edge of the front flange of the FOUP to form the proximity seal with the front flange of the FOUP; and the lower seal plate is mounted to the recessed shoulder, extends up, and terminates just below a lower edge of the front flange of the FOUP to form a proximity seal with the front flange of the FOUP, and wherein the port door is sized to fit within an aperture that is smaller than a reduced aperture formed by the tool interface and the seal plate, the variable lot size load port assembly further having (a) an upper extension plate attached to the port door, the upper extension plate extending vertically up from the port door to occlude an upper portion of the aperture when the port door is in the closed position, and (b) a lower extension plate attached to the port door, the lower extension plate extending vertically down from the port door to occlude a lower portion of the aperture when the port door is in the closed position.