Substrate transfer apparatus

A substrate transfer apparatus for transferring a substrate between a core chamber and a peripheral chamber, wherein the core chamber is connected to a first chamber and a second chamber, each of the first and second chambers being arranged as the peripheral chamber, the substrate transfer apparatus comprising:

• a transfer robot arranged in the core chamber and including an arm, wherein the arm is capable of extending/drawing and pivoting a hand for carrying the substrate so as to transfer the substrate from the first chamber serving as an initial point to the second chamber serving as a terminal point;
• a first sensor which detects an edge surface of the substrate at a first detection point associated with the initial point, wherein the first sensor is arranged at a position that the edge surface of the substrate passes by when the hand is extended/drawn between the core chamber and the first chamber and that the edge surface of the substrate passes by when the hand is pivoted in the core chamber;
• a second sensor which detects the edge surface of the substrate at a second detection point associated with the terminal point;
• and
• a control unit which controls the first sensor, the second sensor, and the transfer robot, wherein the control unit:
• sets a movement route for the hand so that a first selection point, located on the edge surface of the substrate in a first direction in which the hand is extended/drawn, and a second selection point, located on the edge surface of the substrate in a second direction in which the hand is pivoted, pass by the first detection point, and a third selection point, located on the edge surface of the substrate in the second direction, passes by the second detection point;
• drives the transfer robot and moves the hand from the initial point along the movement route;
• detects the first selection point and the second selection point with the first sensor at the first detection point and then detects the third selection point at the second detection point with the second sensor;
• calculates the location of the center of the substrate based on the detection result of the first and second sensors;
• and
• transfers the substrate to the terminal point based on the calculated location of the center of the substrate, and
• wherein the control unit sets the movement route for the hand so that the first selection point, the second selection point, and the third selection point are arranged at equal intervals on the edge surface of the substrate.