Abstract: A system for testing an integrated circuit on a semiconductor wafer so as to achieve low probe needle contact resistance with low probe needle force and without substantial scrubbing includes a probe and supporting a plurality of probe needles electrically coupled to an electrical test system above and in alignment with a plurality of contact pads of the integrated circuit, respectively. The wafer is mechanically moved to press probe needles to bring a tip of each probe needle into physical contact with a corresponding contact pad, and is further moved to increase a needle force of each tip against the corresponding contact pad and cause flexing of a curved portion of each probe needle. Each probe needle is curved such that the flexing causes the tip of each probe needle to rock without appreciable sliding on the surface of the contact pad.

Abstract: A probe card assembly includes a probe card, an interposer and a probe array. The probe array includes a plurality of closely spaced pins, each pin includes a post and a beam, and each beam has a first end attached to the top of a post and a second end for contacting an integrated circuit. A bead on the second end of the beam assures that the free end of the beam will contact an IC first. For contacts on a grid, the beams extend diagonally relative to the rows and columns of the grid, enabling the beams to be longer. For contacts in a row on centers closer than the pins, two rows of pins straddle the contacts and the beams extend toward the contacts from opposite sides of the contacts. The probe array can be formed on the high density side of the interposer.