Fabrication of BeCu module probe array using heating and fusing currents

Abstract

We have developed a novel probe array using BeCu sheets, to solve the high-production-cost problem associated with conventional MEMS probe cards. The BeCu probe has a simple structure and offers several advantages such as ease of fabrication and rapid prototyping; further, the fabrication process is cost-effective. The proposed array was fabricated by applying a suitable heating current (for plastic deformation via Joule heating) and fusing current (for cutting the array) to a BeCu beam. The stress relaxation time was 7 min during the application of a heating current of 4 A, and the fusing current was 20 A. The fabricated probe array is suitable for use in various complicated semiconductor chip tests.

Probe Array from BeCu Metal Sheet Using Heat and Fusing Currents

“…The BeCu metal sheet was etched with FeCl 3 solution after photolithography with AZ 1512 photoresist to form the probe array. In regard to bonding the two substrates, Figure 4 shows the process of bonding, annealing, and cutting the probe array [13,18]. The BeCu metal sheet and silicon substrate were bonded with solder paste under the reflow conditions described above (see Figure 4(a)).…”

“…The dimensions of the BeCu beam were 30 mm × 5 mm. The beam was bent, and the ends of the bent beam were 7.2 mm apart [13,18]. Current was applied to both ends of the beam to perform the annealing.…”

“…The heat current is expressed as the rate of heat exchange between molecules. The fusing current of a wire is the current that will cause it to overheat, melt, and thus create an open circuit; in this case the wire is acting like a fuse [13,14]. The fusing current affects the circuit as follows.…”