In the process of production of an IC device or other electronic device, an electronic device test apparatus is used for testing the performance and functions of an IC device in a state built into the semiconductor wafer and in a packaged state.
As the electronic device test apparatus 1′ for testing the electrical characteristics of an IC device formed in a semiconductor wafer W, as shown in FIG. 8, one which pushes a wafer W by a prober 80 against a probe card 50′, brings probe needles 60′ mounted on the probe card 50′ into electrical contact with the input/output terminals of an IC device, and tests the electrical characteristics of the IC device by a tester (not shown) through the probe card 50′ and test head 10 has been known in the past.
This test is performed in the state applying thermal stress to the wafer W by heating a prober stage 83 holding the wafer W under test. Along with the application of this thermal stress, the probe card 50′ also rises in temperature and expands due to the heat.
The board 55′ on which the probe needles 60′ are mounted in the probe card 50′ is, for example, made of a glass epoxy resin or another material with a larger coefficient of thermal expansion than the semiconductor wafer W. Further, as shown in the same figure, the probe card 50′ is fixed to a top plate 81 of the prober 80 at its peripheral edges via a card holder 70.
For this reason, if thermal stress is applied to the wafer W, as shown in FIG. 9A to FIG. 9C, the board 55′ of the probe card 50′ expands due to heat and deforms in the vertical direction whereby the front end positions of the probe needles 60′ move in the vertical direction. Due to this, the needle pressure (contact pressure) by which the probe needles 60′ contact the input/output terminals of an IC device changes, so the electrical characteristics between the probe needles 60′ and the input/output terminals of an IC device end up changing and high precision tests cannot be performed in some cases.
Further, if the board 55′ on which the probe needles 60′ are mounted in the probe card 50′ expands due to heat, sometimes positional deviation occurs between the probe needles 60′ and the input/output terminals of an IC device and the probe needles 60′ end up missing contact with the input/output terminals.