Electromechanical Performance of Microprobe Test With Cuboid Magnetorheological Damper in Microelectronic Packaging

To avoid the damage of the microprobe to the wafer, the magnetorheological (MR) damping loading was used. The problem of low repeated positioning was solved by limiting the relative rotation between the probe and cylinder. The experimental results show that the damping performance was similar between the cuboid and cylinder damper. The repetition accuracy of cuboid was more than circular cylinder damper two times. Then, the electrical properties of probe with the cuboid damper were tested under different damping currents, loading velocities, and loading displacements, and the contact resistances fluctuated in the range of 0.85-1.4 \Omega . Finally, the mathematical models of pressure and contact resistance were established using the loading speed of 20 mm/s and loading displacement of 300 \mu \text{m} . The relationship between the pressure and contacting resistance of probe was revealed with the new damper during loading process and unloading process.