A Comparison Study of High-frequency Characteristics for Ball and Ribbon Bonding

摘要

In many microwave applications above 10 GHz, ribbon wire bonding is usually used because of its high frequency and high power characteristics. In general, ribbon bonding with a rectangular-shaped wire will provide lower impedance and inductance at higher frequency than a round wire. However, these results were not reached under a fair comparison for ribbon and round wires. In this article, two objective comparisons for these two wires were compared under the same wire cross-section and surface area. Therefore, three types of bonding wires were measured up to 20 GHz individually to analyze their high-frequency characteristics of self-inductance, insertion loss (IL) and self-resonant frequency (f_(SR)) with the same cross-section or surface area conditions. Based on the measurements, two wires with the same surface area provide very similar characteristics due to the skin effect. It clearly demonstrates that the surface area of bonding wire determines the current carrying ability instead of the cross-section area, and dominates the high-frequency performance of the wire.