New fabrication method of micro-pyramidal vertical probe array for probe cards

This paper presents a novel and precision process to fabricate an array of micro metal vertical probes with various tip angles. The process includes an inclined and multiple ultraviolet (UV) lithography, contact lithography and Ni electroforming technology. The tips of micro pyramid vertical probe array utilize the inclined and multiple exposures cooperated with Snell´s law. Due to the light pass through an optical transparent homogenous material, the material refractive index results in light path deflection. By changing the workpiece inclination, controllable various tip angles can be fabricated. The experimental results showed that micro metal vertical probes with 54deg, 60deg and 68deg tip angles. The micro-pyramidal vertical probe array can be used in vertical-type probe cards without the conventional complicated assembly.