An adjustable length frog-leg type wafer handler is provided. The wafer handler has two arms each having an upper portion and a lower portion. The lower portion may extend between a normal position and an extended position, and/or the upper portion may extend between an normal position and a compressed position. The adjusted positions (i.e., extended or compressed) are assumed as the wafer handler moves through a center position. Thus, the inventive wafer handler has a normally smaller arm length (as compared to conventional frog leg configurations) which in turn allows a smaller core axis of rotation (i.e., a smaller bladeless arm length). Therefore the blade used with the adjustable wafer handler may be longer by an amount equal to the difference between the normal and the adjusted arm lengths, without increasing the overall (i.e., the length of the arm and blade) retracted axis of rotation. The longer blade allows wafer placement within a processing chamber without requiring the wafer handler itself to enter the processing chamber.
The present invention generally provides a robot that can transfer workpieces, such as silicon wafers, at increased speeds and accelerations and decelerations. More particularly, the present invention provides a robot wrist associated with the robot arm for mechanically clamping a workpiece to a workpiece handling member attached to the arm. The wafer clamp selectively applies sufficient force to hold the workpiece and prevent slippage and damage to the workpiece during rapid rotation and linear movement of the handling member. In a particular embodiment, a clamp for securing silicon wafers uses a flexure assembly to position and hold the wafer with minimal particle generation and wafer damage. The clamp is designed so that the wafers are normally clamped near full extension of the workpiece handling member to deliver or pick up a wafer. A particular embodiment uses a pneumatic cylinder to actuate the flexure assembly so that the flexure assembly moves outwardly and rearwardly away from the wafer when actuated at or near full extension of the workpiece handling member.
