Ultra-Compact, High-Performance, 3D-IPD Integrated Using Conformal 3D Interconnects

• Published in: 2018 IEEE 68th Electronic Components and Technology Conference (ECTC) pp. 1082 - 1088
• Main Authors: Ghannam, Ayad, Magnani, Alessandro, Bourrier, David, Parra, Thierry
• Format: Conference Proceeding
• Language: English
• Published: IEEE 01.05.2018
• Subjects: 3D interconnect; 3D IPD; Balun; Band-pass filters; component; Filter; Glass; Glass substrate; Inductance; Inductor; Inductors; RF-MCM; RF-SiP; Solenoids; Substrates; Three-dimensional displays; Transformer; WLAN
• ISSN: 2377-5726
• DOI: 10.1109/ECTC.2018.00166

A 3D technology for fabrication of ultra-compact, high-performance 3D integrated passive devices (3D-IPD) is presented here. The technology comprises high-Q thin film MIM capacitors and high-Q 3D inductors/transformers fabricated on glass substrate using conformal 3D interconnects. MIM capacitors with a capacitance density of 310 pF/mm 2 are fabricated using low temperature Si 3 N 4 insulator. 3D solenoid inductors/transformers are fabricated using two 15μm thick copper layers, with the second one being 3D and conformal. 3D inductor's/transformer's shape and copper thickness are optimized to increase inductance density, reduce RF losses and enable high power handling. 3D-Components for WLAN applications, such as filters and baluns, have been synthesized, simulated and fabricated using 3D-IPD technology. These devices exhibit low loss and occupy a surface smaller than 1 mm 2 . For example, a 2.4 GHz band-pass filter exhibits -1.7 dB insertion loss and occupies 0.64 mm 2 , whereas, a 5 GHz one exhibits -1.45 dB insertion loss and occupies 0.5 mm 2 . Simulation and measurement results of these devices are presented and discussed in detail in this paper. This new technology will enable integration of ultra-compact, high performance 3D-IPD and will lead to smaller system packages, such as RF-MCM and RF-SiP.