PURPOSE: To easily and positively detect at which port an object to be machined is set and to achieve machining by a different recipe for each port part by providing a bar code indicating the ID of the port at or near the port.

CONSTITUTION: When a wafer carrier 5 is set to a certain port, for example a port 44, of a machining device 3a, a bar code 7 of the wafer carrier 5 is read first by a bar code reader 9 and then a port 4 is read, Immediately after that, a recipe start signal is automatically transmitted from a controller 2 to the machining device 3a. The machining device 3a performs process treatment when it receives the recipe start signal. Then, when the process treatment is completed, the wafer carrier 5 is released from the machining device 3a. The bar code 7 of the wafer carrier 5 and the bar code 10 of the set port 44 are read and then the wafer carrier 5 and the port 4 are reported to a host 1.