Abstract: A tray transfer arm 205 capable of holding and releasing a customer tray KST is movable in a Z-axis direction by a Z-axis drive, and the Z-axis drive is capable of switching a moving operation from a normal operation to a torque restriction operation while moving the tray transfer arm 205 downward in the Z-axis direction.

Abstract: A tray transfer arm 205 capable of holding and releasing a customer tray KST is movable in a Z-axis direction by a Z-axis drive, and the Z-axis drive is capable of switching a moving operation from a normal operation to a torque restriction operation while moving the tray transfer arm 205 downward in the Z-axis direction. According to the tray transfer arm 205 as above, it is not necessary to provide an elevator to each of stockers for storing the customer trays KST and to accurately perceive a height of the customer tray KST or the loaded height and, furthermore, a moving speed of the tray transfer arm 205 at a position not requiring any torque restriction can be maintained high.

Abstract: An IC testing apparatus 1 for performing a test by applying at least a low temperature stress to ICs to be tested comprising a refrigerant cycle 210 wherein at least a compressor 211, condenser 212, expansion valve 214 and evaporator 215 are connected in this order, and a cold air applying line 220 having a blower 223 for supplying heat exchanged cold air by the evaporator 215 to the ICs to be tested.

Abstract: An automatic testing system and method for inspecting the contact characteristics of the contact pins of each of sockets of an IC tester disposed in the testing zone of an IC handler in an automatic and efficient fashion prior to testing semiconductor devices under test is provided. A test device which is identical in shape to semiconductor devices to be tested and the electric characteristics of which are known is provided and is carried on a test tray and conveyed from the loader section to the testing zone where the test device is brought into contact with a socket to measure the contact characteristics of the socket. Upon completion of the measurement, the test device is transferred from the test tray to the customer tray, and the customer tray with the test device thereon is then temporarily stored in a tray storing means in the unloader section. Thereafter, the customer tray is conveyed to the loader section where the test device is transferred from the customer tray to the test tray.

Abstract: A cemented carbide of the invention contains at least one of cobalt and nickel; calcium, sulfur, aluminum, silicon and phosphorus; balance tungsten carbide; and unavoidable impurities. The content of cobalt or nickel should range from 4 to 35% by weight. The content of each of calcium, sulfur, aluminum and silicon should be no greater than 50 ppm by weight, while the content of phosphorus should be no greater than 20 ppm by weight. The tungsten carbide has an average crystal grain size of 0.2 to 1.5 micrometers. The cemented carbide may further contain 0.1 to 40% by weight of at least one compound which may be carbides of metals in Groups IVa, Va and VIa of the Periodic Table other than tungsten, nitrides of metals in Groups IVa and Va of the Periodic Table and solid solution of at least two of the carbides and nitrides.

Abstract: A cemented carbide contains a binder phase of 4 to 35% by weight of at least one of cobalt and nickel, 1 to 50 ppm by weight of impurities and a hard dispersed phase of balance tungsten carbide. The tungsten carbide has an average crystal grain size ranging from 0.2 to 1.5 .mu.m. The grain size of the impurities is not larger than 10 .mu.m. The binder phase has an average crystal grain size of 5 to 400 .mu.m. The cemented carbide may contain a binder phase of 4 to 35% by weight of at least one of cobalt and nickel, 1 to 50 ppm by weight of impurities, and a hard dispersed phase of 0.1 to 40% by weight of at least one compound and balance tungsten carbide. The compound may be carbides of metals in Groups IV.sub.A, V.sub.A and VI.sub.A of the Periodic Table other than tungsten, nitrides of metals in Groups IV.sub.A and V.sub.A of the Periodic Table or solid solution of at least two of the carbides and nitrides.