Abstract
This paper presents a chip-level integration of radio-frequency (RF) microelectromechanical systems (MEMS) air-suspended circular spiral on-chip inductors onto MOSIS RF circuit chips of LNA and VCO using a multi-layer UV-LIGA technique including SU-8 UV lithography and copper electroplating. A high frequency simulation package, HFSS, was used to determine the layout of MEMS on-chip inductors with inductance values close to the target inductance values required for the RF circuit chips within the range of 10%. All MEMS on-chip inductors were successfully fabricated using a contrast enhancement method for 50 μm air suspension without any physical deformations. High frequency measurement and modeling of the integrated inductors revealed relatively high quality factors over 10 and self-resonant frequencies more than 15 GHz for a 1.44 nH source inductor and a 3.14 nH drain inductor on low resistivity silicon substrates (0.014 Ω cm). The post-IC integration of RF MEMS on-chip inductors onto RF circuit chips at a chip scale using a multi-layer UV-LIGA technique along with high frequency measurement and modeling demonstrated in this work will open up new avenues with the wider integration feasibility of MEMS on-chip inductors in RF applications for cost-effective prototype applications in small laboratories and businesses.
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References
Arcioni P, Castello R, Astis GD, Sacchi E, Svelto F (1998) Measurement and modeling of Si integrated inductors. IEEE Trans Instrum Meas 47(5):1372–1378
Carchon GJ, De Raedt E, Beyne E (2004) Wafer-level packaging technology for high-Q on-chip inductors and tansmission line. IEEE Trans Microw Theory Tech 52(4):1244–1251
Chang JYC, Abidi AA, Gaitan M (1993) Large suspended inductors on silicon and their use in a 2-μm CMOS RF amplifier. IEEE Electron Dev Lett 14(5):246–248
Chua CL, Fork DK, Van Schuylenbergh K, Lu JP (2003) Out-of-plane high-Q inductors on low-resistance silicon. J MEMS 12(6):989–995
Dec A, Suyama K (2000) A 1.9-GHz CMOS VCO with micromachined electromechanically tunable capacitors. IEEE J Solid-State Circuits 35(8):1231–1237
Dodo H, Aoki Y, Hayama N, Fujii M, Yamaguchi Y, Sasaki Y, Ohba H, Hida H (2003) A low-power and variable-gain transceiver front-end chip for 5-GHz-band WLAN applications. Symposium Digest 2003 IEEE MTT-S International Microwave Symposium 3:1559–1562
Erben U, Sonmez E (2004) Fully differential 5 to 6 GHz low noise amplifier using SiGe HBT technology. Electron Lett 40(1):39–40
Jeong Y, Doh H, Jung S, Park DS, Lee J-B (2004) CMOS VCO & LNA implemented by air suspended on-chip RF MEMS LC. 2004 IEEE International Midwest Symposium on Circuits and Systems (MWSCAS 2004) 373–376
Katehi LPB, Harvey JF, Brown E (2002) MEMS and Si micromachined circuits for high-frequency applications. IEEE Tran Microw Theory Tech 50(3):858–866
Kim CS, Park M, Kim C-H, Hyeon YC, Yu HK, Lee K, Nam KS (1998) A fully integrated 1.9-GHz CMOS low-noise amplifier. IEEE Microw Guided Wave Lett 8(8):293–295
Lu H, Pillans B, Lee J-B (2004) Micromachined on-chip high aspect ratio air core solenoid inductor for multi-GHz applications. Symposium Digest 2004 IEEE MTT-S International Microwave Symposium 2:881–884
Lu H, Pillans B, Lee J-C, Kim K, Lee J-B (2007) High aspect ratio air core solenoid inductors using an improved UV-LIGA process with contrast enhancement material. Microsyst Technol 13(3–4):237–243
Nishikawa K, Piernas B, Kamogawa K, Nakagawa T (2002) Compact LNA and VCO 3-D MMICs using commercial GaAs PHEMT technology for V-band single-chip TRX MMIC. Symposium Digest 2002 IEEE MTT-S International Microwave Symposium 3:1717–1720
Park E-C, Choi Y-S, Yoon J-B, Hong S, Yoon E (2003) Fully integrated low phase-noise VCOs with on chip MEMS inductors. IEEE Tran Microw Theory Tech 51(1):289–296
Park DS-W, Kim K, Pillans B, Lee J-B (2004) PDMS-based pattern transfer process for the post-IC integration of MEMS onto CMOS chips. J Micromech Microeng 14(3):335–340
Rebeiz GM (2003) RF MEMS, Theory, Design, and Technology. Wiley, London
Reynolds SK, Floyd BA, Beukema TJ, Zwick TA (2003) Direct-conversion receiver integrated circuit for WCDMA mobile systems. IBM J Res Dev 47(2–3):337–353
Svelto F, Castello R (2002) A bond-wire inductor-MOS varactor VCO tunable from 1.8 to 2.4 GHz. IEEE Tran Microw Theory Tech 50(1):403–407
Tang C-C, Wu C-H, Liu S-I (2002) Miniature 3-D inductors in standard CMOS process. IEEE J Solid-State Circuits 37(4):471–480
Tilmans HAC, De Raedt W, Beyne E (2003) MEMS for wireless communications: ‘from RF-MEMS components to RF-MEMS-SiP. J Micromech Microeng 13(4):S139–S163
Vassiliou I, Vavelidis K, Georgantas T, Plevridis S, Haralabidis N, Kamoulakos G, Kapnistis C, Kavadias S, Kokolakis Y (2003) A single-chip digitally calibrated 5.15–5.825-GHz 0.18-μm CMOS transceiver for 802.11a wireless LAN. IEEE J Solid-State Circuits 38(12):2221–2231
Woerlee PH, Knitel MJ, van Langevelde R, Klassen DBM, Tiemeijier LF, Scholten AJ, Duijnhoven ATAZ (2001) RF-CMOS performance trends. IEEE Trans Electron Dev 48(8):1776–1782
Yao JJ (2000) RF MEMS from a device perspective. J Micromech Microeng 10(4):R9–R38
Acknowledgments
This work was supported in part by the National Science Foundation under the grant ECS-0296108. The authors would like to thank PVA TePla for equipment support (TePla 300 microwave plasma etch system). The supports of UTD clean room staffs and UTD Micro/Nano Devices and Systems Laboratory are acknowledged.
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Park, D.SW., Jeong, Y., Lee, JB. et al. Chip-level integration of RF MEMS on-chip inductors using UV-LIGA technique. Microsyst Technol 14, 1429–1438 (2008). https://doi.org/10.1007/s00542-007-0532-9
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DOI: https://doi.org/10.1007/s00542-007-0532-9