The present invention has a first optical detection mark having a predetermined
positional coordinate in a lateral direction with respect to a carrier opening
of a processing unit through which a carrier apparatus enters and exits, a second
optical detection mark having a predetermined positional coordinate in a vertical
direction with respect to the carrier opening, and an optical sensor provided on
the substrate carrier apparatus for detecting the first or second optical detection
mark. The substrate carrier apparatus is rotated by a predetermined angle from
a position of the substrate carrier apparatus where the optical sensor detects
the first optical detection mark, and the substrate carrier apparatus is moved
in the vertical direction by a predetermined amount of movement from a position
of the substrate carrier apparatus where the optical sensor detects the second
optical detection mark. After the substrate carrier apparatus faces the carrier
opening of the processing unit, the substrate carrier apparatus is allowed to enter
the processing unit to acquire in advance a precise transfer position when transferring
a substrate to a predetermined position on a mounting table in the processing unit.
