Abstract: A tray, on which IC elements to be tested are arranged at a pitch P1, is disposed at a first position, a performance board, which has a plurality of testing stations at a pitch P2, is disposed at a second position, and an IC chuck carrier is guided between the first and second positions by X-axis and Y-axis rails. The IC chuck carrier has a plurality of chuck heads arranged in a line and the pitch of arrangement of the chuck heads is selectively set, by a pitch switching device, to the pitch P1 or P2. The chuck heads are set to the pitch P1 on the tray and simultaneously chuck up therefrom a plurality of IC elements. Then, the chuck heads are brought to the second position, where the pitch of the chuck heads is switched to P2 and the IC chucked by the chuck heads are simultaneously attached to the plurality of testing stations.

Abstract: An IC element supplied to a testing station is guided by a rail and a guide member to move by its own weight. At least one of the rail and guide member has built therein plate-shaped ceramic heater or plate-shaped silicone rubber heater. The guide member urges the IC element against the rail to heat the IC element. An auxiliary stopper is provided opposite but aslant to the IC element sliding surface of the rail. The IC element moving on the rail is yieldingly urged by the auxiliary stopper against the sliding surface of the rail, braked and engages an engaging piece at the lower end of the auxiliary stopper. The IC element is disengaged from the engaging piece to slightly move and stopped by a main stopper, where the IC element is tested. A plurality of such testing passages are provided, and IC elements simultaneously tested in the testing passage are fed to discharge rails respectively corresponding thereto.