Abstract: A probe card is electrically connected to a tester, electrically contacted and connected to circuits to be tested, and used to transmit test signals between the tester and the circuits. It includes a plate assembly having a printed board and an earth plate insulated from each other. Probe assemblies are supported by the plate assembly and are substantially vertically contacted at their foremost ends with pads of the circuits to be tested. Each probe assembly includes a center conductor having a sharpened tip contacted with the pad of the circuit to be tested. A holder conductor shrouds the center conductor while leaving the front end portion thereof not enclosed, and having electrical continuity with the center conductor. A dielectric shrouds the holder conductor, a peripheral conductor coaxially arranged around the holder conductor with the dielectric interposed between them, and a sheath enclosing the peripheral conductor.

Abstract: A probe apparatus tests the electrical characteristics of chips formed on a semiconductor wafer by bringing probes into contact with pads of each chip. The probes, which include ones for power supply potentials, signals, and ground potential, are mounted vertically penetrating a ring block which is attached to the center of a main PCB of a probe card. A tray containing a number of fuses is mounted over the probe card by means of struts. The fuses in the tray connect wires of the main PCB, to which the supply potential of a DC power source is applied, and their corresponding probes. The fuses and the tray can be collectively removed from the probe card to be replaced with new ones.