Li Liguan, Lan Di, Han Xu, Liu Tinghung, Dewdney Julio, Zaman Adnan, Guneroglu Ugur, Martinez Carlos Molina, Wang Jing
Department of Electrical Engineering, University of South Florida, 4202 E. Fowler Avenue, Tampa, FL 33620, USA.
Coherence. Inc., 375 Saxonburg Boulevard, Saxonburg, PA 16056, USA.
Micromachines (Basel). 2025 Jun 26;16(7):755. doi: 10.3390/mi16070755.
This paper presents the first demonstration and comparison of two identical oscillator circuits employing piezoelectric zinc oxide (ZnO) microelectromechanical systems (MEMS) resonators, implemented on conventional printed-circuit-board (PCB) and three-dimensional (3D)-printed acrylonitrile butadiene styrene (ABS) substrates. Both oscillators operate simultaneously at dual frequencies (260 MHz and 437 MHz) without the need for additional circuitry. The MEMS resonators, fabricated on silicon-on-insulator (SOI) wafers, exhibit high-quality factors (), ensuring superior phase noise performance. Experimental results indicate that the oscillator packaged using 3D-printed chip-carrier assembly achieves a 2-3 dB improvement in phase noise compared to the PCB-based oscillator, attributed to the ABS substrate's lower dielectric loss and reduced parasitic effects at radio frequency (RF). Specifically, phase noise values between -84 and -77 dBc/Hz at 1 kHz offset and a noise floor of -163 dBc/Hz at far-from-carrier offset were achieved. Additionally, the 3D-printed ABS-based oscillator delivers notably higher output power (4.575 dBm at 260 MHz and 0.147 dBm at 437 MHz). To facilitate modular characterization, advanced packaging techniques leveraging precise 3D-printed encapsulation with sub-100 μm lateral interconnects were employed. These ensured robust packaging integrity without compromising oscillator performance. Furthermore, a comparison between two transistor technologies-a silicon germanium (SiGe) heterojunction bipolar transistor (HBT) and an enhancement-mode pseudomorphic high-electron-mobility transistor (E-pHEMT)-demonstrated that SiGe HBT transistors provide superior phase noise characteristics at close-to-carrier offset frequencies, with a significant 11 dB improvement observed at 1 kHz offset. These results highlight the promising potential of 3D-printed chip-carrier packaging techniques in high-performance MEMS oscillator applications.
本文展示了两个采用压电氧化锌（ZnO）微机电系统（MEMS）谐振器的相同振荡器电路的首次演示和比较，这两个电路分别在传统印刷电路板（PCB）和三维（3D）打印的丙烯腈丁二烯苯乙烯（ABS）基板上实现。两个振荡器同时在双频（260 MHz和437 MHz）下工作，无需额外电路。在绝缘体上硅（SOI）晶圆上制造的MEMS谐振器具有高品质因数（），确保了卓越的相位噪声性能。实验结果表明，与基于PCB的振荡器相比，采用3D打印芯片载体组件封装的振荡器在相位噪声方面有2 - 3 dB的改善，这归因于ABS基板较低的介电损耗和射频（RF）下降低的寄生效应。具体而言，在1 kHz偏移时实现了 - 84至 - 77 dBc/Hz的相位噪声值，在远离载波偏移时实现了 - 163 dBc/Hz的本底噪声。此外，基于3D打印ABS的振荡器输出功率明显更高（260 MHz时为4.575 dBm，437 MHz时为0.147 dBm）。为便于进行模块化表征，采用了先进的封装技术，利用具有亚100μm横向互连的精确3D打印封装。这些技术确保了强大的封装完整性，同时不影响振荡器性能。此外，对两种晶体管技术——硅锗（SiGe）异质结双极晶体管（HBT）和增强型赝本征高电子迁移率晶体管（E - pHEMT）——的比较表明，SiGe HBT晶体管在接近载波偏移频率时提供了卓越的相位噪声特性，在1 kHz偏移时观察到显著的11 dB改善。这些结果突出了3D打印芯片载体封装技术在高性能MEMS振荡器应用中的广阔前景。
