To provide an inexpensive constitution in small size, and facilitate control of conveying action, so that a cycle time required for conveyance of a sample between a cassette and a loading base can be shortened, by arranging the first/second arms with a fixed space apart, and making the cassette and the loading base respectively vertically movable.

After ending inspection relating to a semiconductor wafer 22 of an inspection bed 23, the inspection bed 23 stops absorption to be lowered down. A waiting unloader arm 27 receives the semiconductor wafer 22 from the inspection bed 23 attracted. Thereafter, the wafer is conveyed to a work cassette 21, attraction is stopped, also the work cassette 21 is a little lifted by an elevator unit, and the semiconductor wafer 22 ending the inspection is stored. During this time, a loader arm 25 conveys the next semiconductor wafer 22 left as taken out to the inspection bed 23, the wafer is loaded on the inspection bed 23 stopping attraction to come rising. In this way, action of the unloader arm 27 and the loader arm 25 is partly duplicated, and treating is performed.