Substrate processing apparatus and transfer method

A substrate processing apparatus comprising:

• a first placement chamber;
• a second placement chamber;
• a transfer robot configured to load and unload an object to be transferred between the first placement chamber and the second placement chamber;
• and
• a controller including a central processing unit (CPU) and memory,
• wherein the controller is configured to:
• a) control the substrate processing apparatus such that a position of the object to be transferred on a fork of the transfer robot is detected as a first position at the time of unloading the object to be transferred from the first placement chamber;
• b) control the substrate processing apparatus such that the object to be transferred is unloaded from the first placement chamber to a standby position of the first placement chamber and then transferred to a standby position of the second placement chamber;
• c) control the substrate processing apparatus such that a position of the object to be transferred on the fork is detected as a second position at the time of loading the object to be transferred from the standby position of the second placement chamber into the second placement chamber;
• and
• d) control the substrate processing apparatus such that a transfer speed of b) is controlled based on the first position and the second position,
• wherein in d), the transfer speed is controlled based on a difference between the first position and the second position, and
• in d), the transfer speed is decreased when the difference exceeds a threshold or in d), the transfer speed is increased when the difference is smaller than or equal to the threshold.