Micro- & Nano-technologies pour applications hyperfréquence à Thales Research &Technology Afshin Ziaei, Sébastien Demoustier, Eric Minoux

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1 Micro- & Nano-technologies pour applications hyperfréquence à Thales Research &Technology Afshin Ziaei, Sébastien Demoustier, Eric Minoux

2 Outline Application hyperfréquence à THALES: Antenne à réseau réflecteur 1 This document and any data included are the property of Thales. They cannot be reproduced, disclosed or used without Thales' prior written approval. Micro-technologies: RF MEMS à THALES Micro-commutateur capacitif ZrO2-MEMS switch ZrO2-MEMS SPDT Power Handling and Life-time of PZT RF MEMS Nano-technologies for RF applications Nano-commutateurs Nano-antennes

3 top surface of the plane θ2 θ1 Reflect Array Antenna Source and/or Receiver 2

4 3 THALES Reflect Array Antenna

5 THALES Reflect Array Antenna Metallic Grid Epoxy radome 4 { ϕ Drivers... ϕ Drivers ϕ Drivers Multilayers electronic board MIRABEL (1998)

6 Wave-guide flange 5 Elementary phase shifter RF-DC decoupling capacitances PIN-diodes

7 MEMS for Power Switching SEM picture Si micro-machined, metal membrane Electrostatic actuation Capacitive switch using high K dielectric material for high Con/Coff ratio (~150) Series or shunt switch designs 6

8 MEMS for Power Switching MEMS technology used : Surface micro-machining Au 3.6 µm TiW / Al 0.7 µm Si 3 N µm TiW/Au 0.6 µm SiO 2 2 µm Au CPW line W = 80 µm S = 120 µm Control electrode (TiW) Si HR or glass substrate Schematic of cross section (Shunt Switch) Holes are etched into the membrane in order to facilitate the membrane delivery 7

9 MEMS for Power Switching 120 µm 120 µm 80 µm 100 µm Control pad GND SGN GND 8

10 SEM pictures of fabricated switches Ground membrane command electrode gap signal RF in signal RF out membrane Ground Gap : g = 3 µm Membrane width : 100 µm Dielectric thickness : g 0 = 0.2 µm 9

11 10 SEM pictures of fabricated switches

12 11 Insertion losses (Membrane in up position) (20 GHz):S 12 : db (40 GHz):S 12 : -0.2 db ,05-0,1-0,15-0,2 Pertes A(dB) -0,25-0,3-0,35 F (GHz)

13 12 Isolation (Membrane in down position) 25 db à 40 GHz Isolation (db)

14 Return losses S 11 Membrane in up position (The membrane is unactuated ) (20 GHz):S 11 : 13 db (40 GHz):S 11 : 10 db GHz measurements S 11 Membrane in down position (The membrane is actuated) S11 (20 GHz):S 11 : 3 db (40 GHz):S 11 : 1 db

15 14 Thales results Results under 0dBm Key characteristics of TRT MEMS RF Switch Isolation 32 db (40 GHz) 18 db (20 GHz) Insertion losses 0.2 db (40 GHz) 0.1 db (20 GHz) Driving voltage V C on 2-3 pf C off ff R on < 2 Ohms Switching time < 5 µs K 81 N/m Mechanical resonance 214 khz

16 15 Line of command 120 plan de masse plan de masse V1 V2 High resistivity resistors Series MEMS switches Conception ON state : Membrane in down position OFF state : Membrane in up position V1 C C on off =109

17 16 SEM pictures of fabricated switches

18 17 How do we improve switch performance? Ground Signal Ground Bridge or membrane Dielectric Rf-On state (membrane Up) Rf-Off state (membrane Down) Increasing switching ratio ( C C on off ) Increasing C down for a given C up

19 18 Influence of K on switch isolation Simulations HFSS Isolation (db) f(ghz) Much higher isolation in DOWN state than previous design Replace Si 3 N 4 with high dielectric constant ZrO 2 film

20 19 SEM pictures of fabricated ZrO2 capacitive switch

21 20 Switch measured characteristics: Insertion loss Shunt ZrO 2 switch characteristics in the UP state 0-0,05-0,1-0,15 Diélectrique ZrO2 (Er = 22) -0,2-0,25 petes d'insertion Insertion loss (db) -0,3-0, fréquence Frequency (GHz)

22 21 Switch measured characteristics: Return loss Shunt ZrO 2 switch characteristics in the UP state Diélectrique ZrO2 (Er = 22) -40 adaptation Return loss (db) fréquence (GHz) Frequency (GHz)

23 22 Switch measured characteristics: Isolation Shunt ZrO 2 switch characteristics in the DOWN state Diélectrique ZrO2 (Er = 22) -40 Isolation isolation (db) fréquence Frequency (GHz)

24 23 Switch measured characteristics: Return loss Shunt ZrO 2 switch characteristics in the DOWN state 0-0,1-0,2-0,3-0,4-0,5 Diélectrique ZrO2 (Er = 22) -0,6-0,7-0,8 Return loss (db) reflexion -0, fréquence (GHz) Frequency (GHz)

25 Signal OUT1 24 MEMS SPDT Switch (ZrO2) Signal IN Signal OUT2 Coplanar Waveguide

26 25 Signal OUT 3 MEMS SPDT Switch (ZrO2) Signal IN 1 On Off Signal OUT 2 THALES design, Serial-serial PZT-PZT

27 MEMS SPDT Switch (ZrO2) without packaging (X band) 0-0,2-0,4-0,6 Membrane down position (S 13 in the on state) -0,8-1 -1,2-1,4 S 13 Magnitude (db) -1,6-1, Frequency Fréquence (GHz) Magnitude (db) S S 33 in the on state (Membrane down position) Frequency Fréquence (GHz)

28 27 MEMS SPDT Switch (ZrO2) without packaging (X band) Membrane up position (in the off state) S 12 Magnitude (db) , , Frequency Fréquence (GHz) -0,06-0,08 Magnitude (db) 1 S ,1-0,12 S 22 in the off state (Membrane up position) -0, Fréquence (GHz) Frequency (GHz)

29 MEMS SPDT Switch (ZrO2) without packaging (X band) 0-5 Membrane up position (in the off state) S S 23 Magnitude (db) Magnitude (db) Fréquence (GHz) Frequency (GHz) Frequency Fréquence (GHz) 28

30 29 Power handling measurements (10 GHz) Power Handling of RF MEMS Capacitive shunt switches GHz Synthesizer TWT-Amplifier DC Power supply Attenuator(1) Directional Coupler DC Bias Tee Spectrum Analyser Attenuator(2) RF Probe DUT Network Analyser Attenuator(4) Attenuator(3) RF Probe

31 30 Power Handling of RF MEMS Capacitive shunt switch PZT Shunt capacitive switch ISOLATION 30 db (10GHz) PERTES INSERTION 0.1dB (10GHz) TENSION D ACTIVATION 25~30Volts RAPPORT Con/Coff 150 GAP D AIR (entre membrane et diélectrique) 0.5 µm Al, 0.2µm TiW 2~2.5µm MEMBRANE 240µm x 100µm Cpw 80µm/120µm/80µm METALLISATION DE LA MEMBRANE CONSTANTE DIELECTRIQUE UTILISEE (PZT) 160~170 VSWR 1.2 Switching time 4 µs under 0dBm (10 GHz)

32 31 Power Handling of RF MEMS Capacitive shunt switch Measured down-state isolation versus input power at 10GHz Isolation (db) Power In (dbm)

33 32 Power Handling of RF MEMS Capacitive shunt switch Measured up-state Insertion Loss versus input power at 10GHz 0-0,05-0,1-0,15 Insertion Loss (db) -0,2-0, Power In (dbm)

34 33 Lifetime measurements (10 GHz) High power RF lifetime of THALES MEMS switch at 10GHz TWT-Amplifier PC-Labview GHz Synthesizer DC Power supply Attenuator(1) Directional Coupler DC Bias Tee Network Analyser Attenuator(2) RF Probe DUT Spectrum Analyser Attenuator(4) Attenuator(3) RF Probe Power Meter

35 34-0,06 RF lifetime of THALES MEMS switch at 10GHz Cold switching (37 dbm) Measured up-state Insertion Loss versus input power at 10GHz -0,07-0,08-0,09-0,1-0,11-0,12-0,13-0,14-0,15-0,16-0,17-0,18-0,19-0,2-0,21-0,22 1,00E+00 1,00E+01 1,00E+02 1,00E+03 1,00E+04 1,00E+05 1,00E+06 1,00E+07 1,00E+08 1,00E+09 1,00E+10 Cycles Insertion Loss (db)

36 35-33,5 RF lifetime of THALES MEMS switch at 10GHz Cold switching (37 dbm) Measured down-state isolation versus input power at 10GHz , , , , ,5 1,00E+00 1,00E+01 1,00E+02 1,00E+03 1,00E+04 1,00E+05 1,00E+06 1,00E+07 1,00E+08 1,00E+09 1,00E+10 Cycles Isolation (db)

37 36 RF lifetime of THALES MEMS switch at 10GHz RF Lifetime at 10 GHz 10 Billion Cycles at 37 dbm 32 Devices Tested at 36 dbm and Room Temp. 25 Devices Completed 10 Billion Cycles (Stopped Test) 6 Devices Completed 1 Billion Cycles (Stopped Test) 1 Device Failed at 0.72 Billion Cycles 8 KHz Cycle Rate 0.69 Billion Cycles/Day 10 Billion Cycles in 15 Days

38 37 CNs switch J. E. Jang et al., Appl. Phys. Lett. 87, (2005) Nanoelectromechanical switches with vertically aligned carbon nanotubes Department of engineering, University of Cambridge

39 38 CNs switch

40 39 TRT Why carbon nanotube based NEMS? High isolation, low losses from MEMS properties Low actuation voltage < 10 V High switching speed ~ a few ns From nanometer size of CNs High power handling exceptional electrical and mechnical properties of CNs High integration density Low cost Low consumption Main difficulty Achieving reproducible and routinely fabrication process of CN switches

41 40 TRT TRT has developed a growth technology of highly homogeneous vertical CNs

42 41 This document and any data included are the property of Thales. They cannot be reproduced, disclosed or used without Thales' prior written approval. TRT Ohmic switch (metal/metal contact) Capacitive switch (metal/dielectric/metal contact)

43 42 TRT Coupling CNs with coplanar waveguides for RF switching

44 CN Antennas 43 Particular electrical properties: High characteristic impedance & high losses High relaxation frequency (>50GHz) High wave velocity (λ/50 - λ/100) Advantages of CN antennas: High integration High density circuits High frequency resonnators Applications of CN antennas: Wireless communications between nano-sized devices/organisms and macroscopic world Antenna arrays at high frequencies Thales: GHz Generator Dipole Radiated Field -λ/4 0 λ/4 Dipole Length I0 Current Distribution This document and any data included are the property of Thales. They cannot be reproduced, disclosed or used without Thales' prior written approval.

45 44 Technical issues: Dipole fabrication: FIB Impedance matching: 50Ω - 10kΩ Emission pattern measurements: Radiation efficiency 60 db CN Antennas

46 45 Conclusion Conclusion Key RF performance characteristics for a Zro 2 -SPDT switch are at 10 Ghz: insertion loss of 0.15 db and isolation of 28 db. RF lifetimes exceeding cycles achieved at input Power level of 36 dbm Research on nanotubes RF NEMS is underway at Thales

47 46 Thank you for your attention

48 47 Bare chip Characteristics: Insertion losses Membrane in up position 0-0,2-0,4-0,6-0,8-1 S12 pzt db -1,2-1,4-1,6-1, Freq GHz

49 GHz measurements db Return losses Freq GHz S11 pzt

50 49 0 Bare chip Characteristics: Isolation ( GHz) Membrane in down position S12 pzt db Freq GHz

51 GHz measurements 0-0,05-0,1 db -0,15-0,2-0,25 Return losses Freq GHz S11 pzt