Process system having locking pin and locking pin

A processing system for performing a fabrication process on a wafer, the processing system comprising:

• a wafer storage cassette that receives at least one wafer;
• one or more process chambers;
• a transfer chamber having a body, a robot huh, a robot arm attached to the robot hub such that the arm can be extended into a position outward from the robot hub or contracted in a position toward the robot huh for moving a blade attached to the robot arm between an extended or contracted position, wherein the body of the transfer chamber is connected to the wafer storage cassette and the one or more process chambers, and the robot arm is configured to transfer the wafer on the blade from the wafer storage cassette through the body of the transfer chamber to one or more of the process chambers;
• and
• a locking pin that detachably attaches to the robot arm when the robot arm is in the contracted position and when attached with the robot arm constrains the robot arm from extending and thereby contra ins the blade from moving or extending in a radial direction from the robot hub toward the body of the transfer chamber and constrains the blade at a predetermined position of the blade within the transfer chamber to prevent the blade from colliding with the body of the transfer chamber.