2012 11-27-masterclass-conductive-inks-kth

Applications with Low-Cost Conductive Inks

iPack Center

Royal Institute of Technology (KTH) Stockholm, Sweden

Outline

Fundamental requirements for flexible electronic applications

Applications DC and RF interconnections & reliability Narrowband and wideband printed antennas Printed chipless RFID Printed wireless sensor Hybrid system for flexible electronics

Masterclass Future of Conductive Printing Nov 27, 2012

Fundamental Requirements of Low-cost Conductive Inks

Good printability/wettability on different substrate Good adhesion/reliability to substrates High conductivity

Typical sheet resistance < 0.1 Ohm/square for radio frequency application

Application-dependent (DC applications) Low sintering temperature: < 150-200℃ required for paper and

low-cost plastic substrate High printing resolution and line edge control


DC and RF Interconnections Substrate-dependence: material, surface roughness, pore size Sintering temp and time strongly affect the sheet resistance


100°C

4-point sheet resistance test pattern printed on PEL paper

Kordak Inkjet photo paper

Schoeller Inkjet photo paper

PEL Electronic grade paper for inkjet

UV Package paper from Korsnäs AB

PE Package paper from Korsnäs AB

[L. Xie et al., Mater. Lett. 2012]

DC and RF Interconnections

Coplanar Wave Guides (CPW) as RF interconnections No double side printing needed Easy to adjust the RF characteristic impedance on both plastic and paper substrate Characterized by VNA and TDR 50 impedance achieved, open the door for RF interconnection on paper

substrate

G S G G St

H

g Ws Wg Wg Ws

CPW CPS

(a) (b)

Masterclass Future of Conductive Printing Nov 27, 2012 [Y. Feng et al., Digital Fabrication 2011]

DC and RF Interconnections

CPW as RF testing vehicles to measure Line resistance, inductance, conductance and capacitance at microwave frequencies Conductance and capacitance are related to substrate properties

Measured CPW parameters Extracted AC properties

Electrical properties of the paper substrate

Masterclass Future of Conductive Printing Nov 27, 2012 [B. Shao et al., ESTC, 2008]

Interconnection Reliability

Interconnection reliability is always an important issue in applications Printed lines initially sintered all at 90 ℃ Aging the printed lines in 85℃/ 85%RH environment up to 6 weeks Monitor the resistance change Resistances decreased after one week and kept stable afterwards Results show that UV package paper shows better reliability than inkjet paper in

the aging test


PEL paper UV package paper [L. Xie et al., Mater. Lett. 2012]

Printed Narrowband UHF RFID Antennas

UHF RFID Meander Line Antennas (866-868 MHz) Simulated by HFSS Printed by inkjet & flexo Experimentally measured in “dark” room Results match well with design High robustness Low ink-consumption


[Y. Amin et al., J Electromagnet. Wave. 2012]

Printed Narrowband UHF RFID Antennas

UHF RFID Bowetie Antennas (860-960 MHz) Simulated by HFSS Printed by inkjet & screen Experimentally measured in “dark” room Results match well with design larger bandwidth

Measured Read Range Input Return Loss Masterclass Future of Conductive Printing Nov 27, 2012

[Y. Amin et al., Prog. Electromagn. Res. 2012]

Printed Wideband Antennas

Wideband Log-Spiral Antennas Log-spiral antennas inkjet printed on paper Experimentally measured in “dark” room Operational range of 0.8-3.0 GHz Accommodate several modules of wireless

sensing or other applications in addition to an RFID tag

Input Return Loss 2D Radiation Pattern Masterclass Future of Conductive Printing Nov 27, 2012

[Y. Amin et al., J Electromagnet. Wave. 2012]

Printed Wideband Antennas

Wideband Archimedean Spiral Antennas Archimedean spiral antennas inkjet printed on paper Experimentally measured in “dark” room Operational range of 0.8-3.0 GHz Simultaneously implementing a wide range of

different modules in addition to an RFID tag

Input Return Loss 2D Radiation Pattern Masterclass Future of Conductive Printing Nov 27, 2012

[Y. Amin et al., Prog. Electromagn. Res. 2012]

Printed Chipless RFID

Inkjet printed Chipless RFID on Paper Time doming reflection principle UWB impulse as interrogation signal 1.67 Gbps data rate Tapered microstrip line to overcome the relative

higher series resistance of inkjet printed lines


[B. Shao et al., Micro. Opt. Techn. Let., 2011]

Printed Chipless RFID

Chipless RFID based on LC-tank Etched or Inkjet printed on plastic and paper substrate Sympathetic Oscillation Principle Possible to work for liquid-bearing applications

Masterclass Future of Conductive Printing Nov 27, 2012 [B. Shao et al., Micro. Opt. Techn. Let., 2012]

[Y. Feng et al., LOPE-C 2012]

Integration With Printed Sensors for Wireless Sensing

Printed Wireless Humidity Sensor f-MWCNTs as sensing material Passive sensor, fully-printable Design adapted for both UHF and UWB applications


0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5-150

-100

-50

0

50

100

150

200

Time (ns)

Volta

ge (m

V)

Interrogation UWB impulse

for UHF application, monitor return loss

for UWB application, monitor the reflected pulse energy

[Y. Feng et al., IEEE Sens. J., 2012]

[Y. Feng et al., IEEE Sens. Conf., 2011]

Hybrid system integration using Inkjet Printing

Hybrid Interconnection Platform Using adhesive to form a smooth step transition

between substrate and packaged components or bared Si IC dies

This smooth ensures that printed metal lines will not break when it crosses over the step difference

To connect bared

Si IC dies

To connect packged

components Masterclass Future of Conductive Printing Nov 27, 2012

[M. Mämtysalo et al., IEEE ECTC, 2012]

Hybrid System for Bio-Medical Applications

Bio-patch Implemented with SoC and Paper-based Inkjet Printing Bio-chip IC SoC Inkjet printed interconnection and electrodes Inkjet printed flexible cables Wearable Bio-patch on paper substrate

Printed Interconnects

Measured ECG signals and FFT using Printed Bio-Patch


[G. Yang et al., IEEE T. Inf. Technol B., in Press]

Low Cost Conductive Ink for Flexible Cables for Wearable ECG Monotoring

Inkjet Printed Flexible Cable for ECG Monitoring

Inkjet printed flexible cable on paper for wearable ECG monitoring

The cable consists of printed metal lines and a shielding line in the middle

The experimental results show that a reliable performance with high quality ECG data is possible on the inkjet printed cable on flexible cable

Measured digitalized ECG signals @ 150 MHz Masterclass Future of Conductive Printing Nov 27, 2012 [Q. Wan et al., IEEE EPEPS, 2011]

Acknowledgements

• Thank you for the financial support from Vinnova (The Swedish Governmental Agency for Innovation Systems) through the Vinn Excellence centers program and the EU Commission under the FP7 CLIP (Conductive Low-cost Ink Project) project.


Thank You!!

Questions?
