Abstract: An apparatus is described for burn-in and/or functional testing of microelectronic circuits of unsingulated wafers. A large number of power, ground, and signal connections can be made to a large number of contacts on a wafer. The apparatus has a cartridge that allows for fanning-in of electric paths. A distribution board has a plurality of interfaces that are strategically positioned to provide a dense configuration. The interfaces are connected through flexible attachments to an array of first connector modules. Each one of the first connector modules can be independently connected to a respective one of a plurality of second connector modules, thereby reducing stresses on a frame of the apparatus. Further features include for example a piston that allows for tight control of forces exerted by terminals onto contacts of a wafer.

Abstract: An electron microscope stage is manually movable in three orthogonal axial directions and two orthogonal rotational directions by corresponding motion transmission systems. Four of the transmission systems employ telescopic rods and a connecting pin having three resilient independently compressible sections. The pin transmits torques from one rod to the other about their longitudinal axes. One section is resiliently secured to an aperture in the inner rod, the other sections are resiliently secured to mating axial slots in the outer rod to permit relative axial displacement of the rods. The independent resilient compression of each section compensates for wear or differences in dimensions between mating surfaces while maintaining tight resilient torque coupling without backlash between the pin and the rods.