Substrate processing apparatus

A method of processing a substrate in a substrate processing apparatus, the method comprising:

• providing the substrate processing apparatus with:
• a frame;
• a SCARA arm pivotally mounted to the frame at a shoulder joint of the SCARA arm, the SCARA arm being a two link arm with at least one end effector dependent therefrom, the two link arm defining an upper arm, including and determining the shoulder joint at one end, and a forearm pivotally joined to the upper arm so as to define an elbow joint of the SCARA arm, each of the at least one end effector being pivotally joined to the forearm at a wrist joint of the SCARA arm, to rotate relative to the forearm about a wrist joint axis, and pass through a slot valve with the wrist joint;
• and
• a drive section with at least one degree of freedom operably coupled via a transmission to the SCARA arm to rotate the SCARA arm about a shoulder axis at the shoulder joint and to articulate the SCARA arm in extension and retraction;
• and
• transporting the substrate with the at least one end effector by extending and retracting the SCARA arm with the at least one degree of freedom;
• wherein:
• the at least one end effector is coupled to a wrist joint pulley, the wrist joint pulley is configured so that SCARA arm extension and retraction effects rotation, relative to the forearm, of the wrist joint pulley and the coupled at least one end effector together as a unit about the wrist joint axis, and
• the wrist joint pulley is coupled to the drive section by a segmented separate transmission band segments, at least one separate band segment is proximate a level edge of the wrist joint pulley adjacent the at least one end effector, and projects out towards the at least one end effector from a level seating surface of the at least one end effector seated against the wrist joint pulley.