3D printed bonds for Mmwave interconnects: a low-complexity, low-loss solution

This work addresses the limitations of traditional bondwires in millimeter-wave (mmWave) chip-to-PCB interconnections, particularly at high frequencies such as those in the E-band. The inherent inductance of bondwires significantly impairs impedance matching and contributes to elevated insertion loss as frequency increases. For instance, a single bondwire with a length of 480 μ m exhibits poor performance, with a return loss (S11) of -2 dB and an insertion loss (S21) of - 4. 6 dB at 7 3 GHz. While using multiple bondwires can offer marginal improvement, the performance remains suboptimal for high-frequency applications. To overcome these limitations, we propose the use of XTPL's Ultra-Precise Dispensing (UPD) technology for forming 3D-printed interconnects. These printed microstructures demonstrate significantly improved RF performance. At 73 GHz, a dual printed bond achieves an insertion loss better than 1 dB and a return loss better than 1 0 dB, highlighting its potential as a superior alternative to traditional wire bonding in mmWave system integration.