A method includes providing a jig including a predetermined center and a magnetron installed on the jig; rotating the magnetron and obtaining a measured first magnetic flux density at the predetermined center of the jig; defining a first area of the magnetron based on the measured first magnetic flux density; rotating the magnetron and measuring a plurality of second magnetic flux densities within the first area of the magnetron; deriving a measured second magnetic flux density among the plurality of second magnetic flux densities; comparing the measured second magnetic flux density with a predetermined threshold; and performing an operation based on the comparison.