Patent ID: 7360985

Claim:
A method for transferring a wafer between a clean box including a box body that has an opening portion at one side thereof and a lid, the method comprising: providing a wafer process apparatus including: a main housing having a window opening at one side thereof; a movable member, on which said clean box is to be placed, provided below the window opening, adapted to be horizontally movable toward and away from said main housing; an air cylinder configured to horizontally move said movable member toward and away from said main housing; an openable/closable door movable into or from an interior of said main housing for closing the window opening; and a stopper configured to stop the movement of said movable member toward said main housing, said method further comprising the steps of: placing said clean box on said movable member; moving said movable member with the clean box toward said main housing, by said air cylinder; stopping the movement of said movable member at once by contacting a surface of the lid of said clean box with a surface of said openable/closable door, with a bias force generated by said air cylinder through the movable member, and holding the lid by said openable/closable door; moving said movable member toward the interior of said main housing while keeping the lid in tandem with said box body and said door; and stopping said movable member by abutting said movable member to said stopper so as to position said box body at a prescribed position but continuously moving the lid toward the interior of said main housing by said openable/closable door, so that the lid is separated from the box body so as to make a wafer transferable between said main housing and the box body, wherein a predetermined clearance is made between a plane on which the opening of the box body opens and a plane on which the window opening opens, when the box body is positioned at the prescribed position, and the predetermined clearance has such a distance that a collision between the plane on which the opening of the box body opens and the plane on which the window opening opens is prevented, irrespective of manufacturing tolerance in the size of the box body and the thickness of the lid.