Apparatus, methods and systems are provided for sealing a door of a slit valve. The invention includes a seal, adapted to extend along a perimeter of a slit valve door; and a hard stop, disposed between the seal and an outer edge of the slit valve door, and adapted to extend along at least a portion of the length of the seal, wherein the hard stop and the seal fill at least a portion of a gap between the slit valve door and a substrate sealing surface. Numerous other aspects are provided.