Prober for highly integrated multichip modules

A prober for function test of LSIs on multichip modules of Hitachi´s newest mainframe M-880 series has been developed. The test is performed by making contact between probes and metallic pads on the module substrate. A visual feedback positioning system is employed to position a probe head, in which the probes are installed, precisely on the module. The prober has four TV cameras to compensate for the location error of module mounting, the location error of probe head holding, and thermal deformation of the module and the prober. Control values of the positioning table, which carries the probe head to a testing point, are calculated by some coordinate transformations with the use of the TV cameras´ outputs and position data measured in the fabrication process of the module and the probe head