Patent ID: 6520733
Filing Date: 2003-02-18
Classification: H01L,Y10S

Abstract:
A substrate transport apparatus for transporting substrates from a substrate loading/unloading section to a processing section, which processes the substrates in accordance with a photolithography process, sequentially one by one, comprising:a plurality of arms for holding a substrate; a &thgr; rotation driving mechanism for rotating the plurality of arms simultaneously around a vertical axis by an angle of &thgr;; an arm back-and-forth moving mechanism for moving each of the plurality of arms, back and forth; a Z-axis driving mechanism for moving the plurality of arms, simultaneously up and down; and a cover assembly surrounding the Z-axis driving mechanism in order to shut out the Z-axis driving mechanism from an outer atmosphere, the cover assembly further comprising: an unmovable slide cover which is not driven by the up-and-down movement of the Z-axis driving mechanism and thus maintained unmoved; an unmovable support member connected to an upside of the unmovable slide cover; a first movable slide cover provided in an outer periphery of the unmovable slide cover and slidably driven by the up-and-down movement of the Z-axis driving mechanism, relative to the unmovable slide cover; a first movable support member connected to an inside of the first movable slide cover, and movable up and down along with the first movable slide cover; a second movable slide cover provided in an outer periphery of the first movable slide cover and slidably driven by the up-and-down movement of the Z-axis driving mechanism, relative to the first movable slide cover; a second movable support member connected to an inside of the second movable slide cover, and movable up and down along with the second movable slide cover; a first slide seal attached to an outer periphery of the first movable support member thereby sealing a clearance between the first movable support member and the unmovable support member; and a second slide seal attached to an outer periphery of the second movable support member thereby sealing a clearance between the second movable support member and the first movable support member; and wherein, when the plurality of arms are moved up by the Z-axis driving mechanism, the first movable support member is moved up along with the first slide cover, with the clearance between the first movable support member and the unmovable support member sealed by the first slide seal, and the second movable support member is moved along with the second slide cover, with the clearance between the second movable support member and the first movable support member sealed by the second slide seal, whereby the first and second movable slide covers slidably move to the unmovable slide cover, with the result that the first and second movable slide covers are located above the unmovable slide cover.