The document summarizes a presentation given at the NORDITE Conference in 2011 on MEMS-based reconfigurable RF systems. It discusses a project between research institutions in Finland, Sweden, and Norway to develop RF MEMS devices, antennas on LTCC substrates, and integrated sub-system modules for applications such as software radios and wireless sensors from 10-40GHz. Challenges in RF MEMS reliability and integration were identified. Commercialization opportunities and related European projects were also mentioned.

1. NORDITE Conference 2011
Quality Hotel 33, Oslo
June 14th, 2011
MEMS Based Reconfigurable RF Systems for Software
Radio, Wireless Sensors, and MMID Technology
(MOSART)
Jussi Varis
VTT Technical Research Centre of Finland
Sweden, FOI: R. Malmqvist, C. Samuelsson
Sweden, Uppsala University: A. Rydberg, X. Hu
Finland, VTT: J. Varis, P. Rantakari, J. Säily, M. Lahti, M. Kaunisto, J. Saijets, and T. Vähä-
Heikkilä

2. Outline
1. Project overview
2. Motivation and applications
3. Produced devices and modules
• RF MEMS Devices
• Antennas on LTCC
• LTCC packaged RF MEMS devices
• Sub-system modules
4. Related on-going efforts
5. Benefits from MOSART
6. Summary
NORDITE Conference 2011, June 14th, 2011 2

3. Project overview
• 36 month VINNOVA, Tekes, and VTT funded project.
• Main goal: Successful integration of MEMS components, active RF circuits, and
sub-systems into a LTCC packaged re-configurable RF front-end demonstrators
at 10-40 GHz.
• Research partners: FOI, Uppsala University (SWE), VTT (FIN)
• Industry partners: Nera Networks (NOR), Ericsson Research (SWE), Saab
Microwave Systems (SWE), Silex Microsystems (SWE), Syncore Technologies
(SWE), Elektrobit Wireless Communications (FIN), Selmic (FIN).
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4. Motivation
• RF MEMS 
 wireless RF systems with better performance
 (compared with a use of today’s of the shelf technologies)
• RF MEMS in point-to-point communication and RF sensing (5-40 GHz),
reconfigurable electronic multi-band (frequency-agile) front-ends 
 Lowers component count, reduces complexity and cost
• RF MEMS switch technology 
 High linearity
 Low insertion loss and DC power consumption  candidate for re-configurable front-
ends and beam steering
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5. Applications
• 35 GHz low loss electrically steerable antennas (low power radars)
• 10-30 GHz re-configurable/tunable amplifiers (for Pt-to-Pt communications)
radio links
mm wave sensors
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6. MOSART RF MEMS devices
VTT 35 GHz analog phase
shifter.
VTT 20-30 GHz SPDT (5.0
mm x 3.0 mm).
FOI 35 GHz 3-bit switched delay
phase shifter (9.3 mm x 3.0 mm).
VTT 30-40 GHz
wideband matching
network
FOI RF MEMS (1.0 mm x 0.9 mm).
switch (0.7 mm x
FOI 20-30 GHz SPDT with
1.0 mm).
places for LNAs (4.5 mm x
3.0 mm).
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7. MOSART antennas on LTCC
VTT 35 GHz co-planar 4x1 antenna
array with EBG structure
(20 mm x 12 mm).
Uppsala 35 GHz 4x1 slot-coupled
antenna array (21.0 mm x 12.5 mm).
Uppsala 20-30 GHz microstrip
bow tie antenna array
(8.0 mm x 18 mm).
VTT 20-30 GHz end-fire dipole antenna
VTT 20-30 GHz Vivaldi antenna
(8.5 mm x 8.0 mm).
(5.7 mm x 17 mm).
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8. MOSART LTCC packaged RF MEMS devices
LTCC packaged wideband RF MEMS LTCC packaged 20-30 GHz RF MEMS SPDT
impedance tuner (9.0 mm x 9.5 mm). switch(12 mm x 9.0 mm).
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9. MOSART sub-system modules
35 GHz narrowband digital phased array 20-30 GHz switchable LNA/driver
Rx module (45 mm x 29 mm). module (16 mm x 15 mm).
25/35 GHz switchable LNA 35 GHz narrowband analog phased
module(20 mm x 11 mm). array Rx module (71 mm x 25 mm).
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10. Main remaining challenges
• RF MEMS reliability
 Process quality (residuals, layer thicknesses).
 Design parameter stability (MEMS switch gap height, capacitance ratio, pull-in
voltage)
 Environmental susceptibility (temperature, mechanical, charging, etc.)
• Integration
 Flip-chip bonding vs. ribbon bonding
 Alignment accuracy on LTCC
 MEMS temperature tolerance in various integration and post integration
phases.
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11. Related on-going efforts
• Rx modules on Taclam. Quartz substrate with RF MEMS
impedance matching networks.
• Tunable LNAs and drivers on quartz.
wire bond
Rx modules on
RX2 Taclam substrates.
LNA/PA
Antenna arrays. MMIC
RX1
or
flip-chip
MMIC
LNAs.
RF MEMS
phase shifters.
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12. Benefits from MOSART
• Nordic countries and Europe have in place technologies to produce
packaged re-configurable radio modules.
 RF MEMS
 LTCC
 MMICs
• Benefits to industry partners in MOSART
 Saab: electrically steerable phased array front-ends for sensor applications
 Nera, Ericsson, Elektrobit: re-configurable/tunable radio sub-systems for Pt-to-Pt
applications
 Syncore: novel integated sub-systems
 Selmic: micro and mm wave frequency LTCC module processing
 Silex: micro and mm wave RF MEMS processing
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13. Benefits from MOSART
• Expanding European frontiers in RF MEMS and LTCC related
development
 MEMS-4-MMIC (EU FP7, 2008-2011, on-chip integration of MMIC and RF
MEMS): OMMIC and CNRS-IEMN (FRA), FOI and Saab (SWE), IMST (GER),
IMT (ROM), VTT (FIN)
 SATURNE (EU FP7, 2010-2013, GaN and RF MEMS for space applications):
UU (SWE), Thales and CNRS-IEMN (FRA), EADS (GER), Thales Alenia
Space (ITA), TopGAN (POL)
 MiniMEMS (EU FP7, 2010-2013, miniaturised RF MEMS for airport and
weather radar systems): ÅAC Microtec and UU (SWE), Thales and CNRS-
IEMN (FRA), Vaisala (FIN)
 MEMSMOD (ESA and participants, 2010-2012, LTCC packaged RF MEMS
switch reliability and environmental testing and assessment): EADS (GER),
Selmic and VTT (FIN)
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14. Towards commercial systems
• RF MEMS switches and sub-systems
(circuits & antennas) have been
demonstrated with state-of-the-art
performance from DC-100 GHz and beyond
• Enabling technology for miniaturized, low-
power high performance re-configurable RF
systems (e.g. for wireless comm., space,
security & defense)
• High reliability (switch cycles) and
fabrication yields needed for a higher market
penetration
• Today, just a few commercial vendors
offering RF MEMS as packaged (discrete)
components: RadantMEMS (US), OMRON
(JPN), DELFMEMS (FR)
• A few MMIC foundries developing RF-
MEMS: OMMIC (FR) – GaAs, IHP (GE) –
SiGe, Selex (IT) – GaN
• RF-MEMS technology in the US (e.g.
Radant) has demonstrated a much higher
TRL than what is currently available in
Europe.
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15. Summary
• MOSART has demonstrated
 RF MEMS matching networks, phase shifters and SPDT switches
 Antenna arrays and wideband antennas on LTCC
 Module concepts for electronically steerable or re-configurable radio systems
 Processing technologies for manufacturing RF MEMS devices and LTCC modules.
• MOSART has
 Brought together a large number of Nordic companies and research institutes.
 Utilised synergy (for example MMIC design and manufacturing) from other related on-
going projects and networks.
 Expanded RF MEMS and LTCC related development to include more Nordic and
European companies and institutes in Nordic, EU, and ESA related projects.
• Challenges remain
 RF MEMS reliability and stability
 Integration related issues.
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16. Contact information
• Project manager and national contact in Finland:
Dr. Jussi Varis, VTT, jussi.varis@vtt.fi, tel: +358-40-569 4089,
fax: +358-20-722 7013
• National contact in Sweden:
Prof. Anders Rydberg, Uppsala University,
anders.rydberg@angstrom.uu.se, tel: +46-18-471 3228, fax:
+46-18-555096
• Chairman of the Steering Group:
 Dr. Robert Malmqvist, FOI Swedish Defense Research
Agency, robert.malmqvist@foi.se, tel: +46-13-378 353, fax:
+46-13-378 519
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