Abstract: A probe card assembly can include a probe head assembly having probes for contacting an electronic device to be tested. The probe head assembly can be electrically connected to a wiring substrate and mechanically attached to a stiffener plate. The wiring substrate can provide electrical connections to a testing apparatus, and the stiffener plate can provide structure for attaching the probe card assembly to the testing apparatus. The stiffener plate can have a greater mechanical strength than the wiring substrate and can be less susceptible to thermally induced movement than the wiring substrate. The wiring substrate may be attached to the stiffener plate at a central location of the wiring substrate. Space may be provided at other locations where the wiring substrate is attached to the stiffener plate so that the wiring substrate can expand and contract with respect to the stiffener plate.

Abstract: A probe card assembly can include a probe head assembly having probes for contacting an electronic device to be tested. The probe head assembly can be electrically connected to a wiring substrate and mechanically attached to a stiffener plate. The wiring substrate can provide electrical connections to a testing apparatus, and the stiffener plate can provide structure for attaching the probe card assembly to the testing apparatus. The stiffener plate can have a greater mechanical strength than the wiring substrate and can be less susceptible to thermally induced movement than the wiring substrate. The wiring substrate may be attached to the stiffener plate at a central location of the wiring substrate. Space may be provided at other locations where the wiring substrate is attached to the stiffener plate so that the wiring substrate can expand and contract with respect to the stiffener plate.

Abstract: A probe card assembly can include a probe head assembly having probes for contacting an electronic device to be tested. The probe head assembly can be electrically connected to a wiring substrate and mechanically attached to a stiffener plate. The wiring substrate can provide electrical connections to a testing apparatus, and the stiffener plate can provide structure for attaching the probe card assembly to the testing apparatus. The stiffener plate can have a greater mechanical strength than the wiring substrate and can be less susceptible to thermally induced movement than the wiring substrate. The wiring substrate may be attached to the stiffener plate at a central location of the wiring substrate. Space may be provided at other locations where the wiring substrate is attached to the stiffener plate so that the wiring substrate can expand and contract with respect to the stiffener plate.

Abstract: An apparatus for determining a planarity of a first structure configured to hold a probing device to the planarity of a second structure configured to hold a device to be probed is disclosed. In one example of the apparatus, a plurality of moveable push rods are disposed in a substrate, which is attached to the first structure. In initial non-displaced positions, the push rods correspond to a planarity of the first structure. The second structure is then brought into contact with the push rods, displacing the push rods into second positions that correspond to a planarity of the second structure. In another example of the apparatus, beams of light are reflected off of reflectors disposed on the first structure and onto sensors disposed on the second structure. The locations of the reflected beams on the sensors are noted and used to determine the planarity of the first structure with respect to the second structure.