Analysis of Bondwires and RF Compensation Circuits in E-Band

Abstract

This article investigates the impact of bondwire interconnections on signal integrity in low and high millimeter-wave (mmWave) applications, emphasizing transmission degradation caused by inductive and parasitic effects. Through detailed measurements and analysis, we demonstrate that transmission loss and impedance mismatches can be effectively reduced by minimizing bondwire length and using multiple wires in parallel. Based on empirical data, we developed an electrical model of bondwire incorporating distributed inductance, capacitance, resistance $(L/C/R)$ , and transmission line characteristics. To further enhance performance, we introduce compact compensation circuits using LC structures and radial stubs optimized for both single and double bondwire configurations. Experimental validation shows that the proposed double-wire LC compensation technique significantly reduces insertion loss—from 5 to 1.5 dB and provides a return loss bandwidth from 70 to 75 GHz. The key novelty of this work lies in integrating multiple bondwires with low complexity, compact LC compensation structures, providing an effective solution for reducing insertion loss and improving impedance matching in mmWave systems. This approach offers a practical and scalable solution for improving chip-to-board and board-to-board interconnect performance in mmWave systems.