US 4,242,038 A · Wafer orienting apparatus

Abstract

An apparatus and method for orienting a substantially flat wafer are described. The wafer preferably has two flat registration edges of unequal length. Upon contact of any edge portion of the wafer with a sensor projecting forwardly from one registration surface, air jets are activated to rapidly rotate the wafer one way until the longer of its two registration edges contacts a sensor projecting forwardly from another registration surface. Then air jets are activated to slowly rotate the wafer the opposite way until said longer registration edge contacts another sensor associated with said other registration surface to effect precise registration of the wafer without overshoot as all three sensor are concurrently contacted and activated. Wafer movement by the jets thereupon terminates and vacuum is applied continuously to hold the wafer in place while the work operation is performed thereon. Since the wafer is registered solely by contact with the various sensor (and not by contact with the respective registration surfaces), contamination of the wafer by physical contact is minimized.

Claims14

Dependent claims

Apparatus for orienting a substantially flat wafer or the like having a flat registration edge, said apparatus comprising:

means providing a flat surface for supporting the wafer and providing a series of directional fluid jet ports,
means extending upwardly from said flat surface and providing two registration surfaces,
sense means associated with each of said registration surfaces,
means for advancing the wafer toward contact with said registration surfaces, and
means controlled by the conditioning of said sense means for controlling selective supply of fluid to said jet ports, including means for rotating the wafer one way until a particular one of said sense means associated with a predetermined one of said registration surfaces is activated, then rotating the wafer the opposite way until sense means in both registration surfaces are concurrently activated for causing wafer motion to be terminated, thereby to prevent overshoot and insure precision registration of the wafer flat registration edge adjacent said predetermined registration surface without contamination and with minimal physical contact defined solely by contact with said sense means.

2 more elements

Dependencies are inferred from the claim text.

Wafer orienting apparatus

Life of this patent

Wafer orienting apparatus

Life of this patent

Abstract

Claims14