M Miller

Publications (5)0 Total impact

• Conference Proceeding: Hermetic wafer-level packaging development for RF MEMS switch

  C. Ferrandon, F. Greco, E. Lagoutte, P. Descours, G. Enyedy, M. Pellat, C. Gillot, P. Rey, D. Mercier, M. Cueff, X. Baillin, F. Perruchot, N. Sillon, L.J. Liu, S. Pacheco, M. Miller
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  ABSTRACT: This paper presents a low temperature (<;;350°C) hermetic solution to fully package at wafer level a RF MEMS switch connecting upwards. The switch has a piezoelectric actuation and an electrostatic hold. In this architecture, the packaging is actually part of the switch itself and shall meet many requirements: 1. Use of Thru-Silicon Via (TSV) for DC and RF connections with minimum via resistance 2. Electrical connection between both wafers 3. Hermetic sealing under controlled atmosphere with 5+/-0.5 μm gap between the switch and the cap wafers 4. No degradation of the switch performances 5. Low temperature (<;;350°C) packaging process to preserve the moving part materials 6. Electrode and dielectric for electrostatic hold 7. No sticking of the moving contact Two main processes were developed and implemented together: Au-Sn eutectic bonding under atmospheric pressure with 5μm spacers to ensure the gap, and 'post-bonding' TSV. The complete process flow of the cap wafer, bonding and TSV process is presented. The solder material, made of 80wt.%Au and 20wt.%Sn, is only 5μm thick and is electroplated. SEM, XPS, EDX analyses and shear tests have been performed. Hermeticity evaluation tests have been set-up, and a standard leak rate lower than 1.2 × 10^-12 mbar.1/s has been demonstrated using the membrane deflexion method. TSV and Au-Sn bump resistance is less than 14mΩ and lOmΩ with a yield of 92% and 98% respectively across the 200mm wafer. The resistance between 2 via is more than 500MΩ at 5V. As to the packaged switch, its insertion losses at 2 GHz are 0.74dB and its off-state isolation is 43.6dB. At last, it has been demonstrated that the substrates resistivity has a great influence on the insertion losses.
  Electronic System-Integration Technology Conference (ESTC), 2010 3rd; 10/2010
• Conference Proceeding: A fully packaged piezoelectric switch with lowvoltage actuation and electrostatic hold

  M. Cueff, E. Defay, P. Rey, G. Le Rhun, F. Perruchot, C. Ferrandon, D. Mercier, F. Domingue, A. Suhm, M. Aid, Lianjiu Liu, S. Pacheco, M. Miller
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  ABSTRACT: This paper reports RF characterization of a fully packaged RF MEMS piezoelectric switch. The switch demonstrates better than 0.8 dB insertion loss at 2 GHz and 30 dB isolation up to 10 GHz. The presented device combines a piezoelectric actuation and a low electrostatic hold voltage to improve contact force. Actuation voltages of the switch are 5 V for both piezoelectric actuation and electrostatic hold. This actuation was sufficient to obtain contact resistance lower than 2 ohms. The switch is packaged by wafer-level packaging technology using gap control, AuSn eutectic bonding and post-process Thru-Silicon Vias.
  Micro Electro Mechanical Systems (MEMS), 2010 IEEE 23rd International Conference on; 02/2010
• Conference Proceeding: Piezoelectric PZT Thin Films in the 100nm Range: A Solution for Actuators Embedded in Low Voltage Devices

  E. Defay, G. Le Rhun, F. Perruchot, P. Rey, A. Suhm, M. Aid, L.J. Liu, S. Pacheco, M. Miller
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  ABSTRACT: This paper reports the piezoelectric properties of sputtered and sol gel PZT thin films investigated in a low thickness range (100-250 nm). Piezoelectric-elastic bimorphs including very thin PZT films were realized and the maximum reachable deflection at 5 V was characterized. The depoling effect experienced by the PZT versus the maximum post process temperature is also discussed which leads to the motivation of developing low thickness range PZT thin films. Elastic-piezoelectric bimorphs were realized and exhibited deflection higher than 5 mum at 5 V. Moreover, these bimorphs showed only a 10% decrease of the deflection after 5 billions cycles.
  Micro Electro Mechanical Systems, 2009. MEMS 2009. IEEE 22nd International Conference on; 03/2009
• Conference Proceeding: Twisted inductors for low coupling mixed-signal and RF applications

  N.M. Neihart, D.J. Allstot, M. Miller, P. Rakers
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  ABSTRACT: Parasitic magnetic coupling is a major design challenge for integrated circuit designers. Fundamentally, it originates in conventional spiral inductors because the magnetic field is not localized, extending far beyond the perimeter. This paper introduces a twisted winding scheme for inductors that increases the localization of the magnetic field, reducing parasitic magnetic coupling by as much as 3100X and the edge-to-edge spacing of inductors by 10X. These results are validated in a 0.18 mum CMOS process.
  Custom Integrated Circuits Conference, 2008. CICC 2008. IEEE; 10/2008
• Conference Proceeding: The MWS 1X4: A High Performance Wavelength Switching Building Block

  T. Ducellier, J. Bismuth, S.F. Roux, A. Gillet, C. Merchant, M. Miller, M. Mala, Y. Ma, L. Tay, J. Sibille, M. Alavanja, A. Deren, M. Cugalj, D. lvancevic, V. Dhuler, E. Hill, A. Cowen, B. Shen, R. Wood
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  ABSTRACT: A novel compact high performance wavelength switch module enables arbitrary routing of 64 DWDM 100 Hz channels from one input into four output ports. 3.5 dB insertion loss, 50 GHz net pass and stop band and 5 W power consumption are obtained
  Optical Communication, 2002. ECOC 2002. 28th European Conference on; 02/2002