Highly Productive Process Technologies of Cantilever type Microprobe Arrays for Wafer Level Chip Testing

This paper describes the highly productive process technologies of microprobe arrays, which were used for a probecard to test a Dynamic Random Access Memory (DRAM) chip with fine pitch pads. Cantilever-type microprobearrays were fabricated using conventional micro-electro-mechanical system (MEMS) process technologies. Bondingmaterial, gold-tin (Au-Sn) paste, was used to bond the Ni-Co alloy microprobes to the ceramic space transformer.The electrical and mechanical characteristics of a probe card with fabricated microprobes were measured by aconventional probe card tester. A probe card assembled with the fabricated microprobes showed good x-y alignmentand planarity errors within ±5 μm and ±10 μm, respectively. In addition, the average leakage current and contactresistance were approximately 1.04 nA and 0.054 ohm, respectively. The proposed highly productive microprobes canbe applied to a MEMS probe card, to test a DRAM chip with fine pitch pads.