Low Temperature Integration of Thin Films and Devices for Flexible and Stretchable Electronics Pooran Joshi, Stephen Killough, and Teja Kuruganti Oak Ridge National Laboratory FIIW 2015
Displays and PV Flexible and Printed Electronic Technology Battery Circuit on Paper Top Cell Design Light Circuit Flexible TFT Antenna on Paper Resonator Glass TCO Antenna OLED Flexible Sensor OPV Active Layer Metal P I N 2 Managed by UT-Battelle Successful Defective Materials Technologies
Technology Space: Internet of Things 3 Managed by UT-Battelle Internet of Everything
IOT Impacting Future Smart Buildings IOT 4 Managed by UT-Battelle
ORNL Can Leverage Unique Capabilities to Impact Energy Use Problem Statement Buildings consume up to 41% of energy produced in the US. Do we have a solution? Technology Solution Advanced sensors and controls have the potential to reduce energy consumption of the buildings by more than 20%. Source: http://www.idsc.ethz.ch Buildings (EERE Goal) Improve building energy efficiency 50 percent, in a cost-effective manner, by 2030. 5 Managed by UT-Battelle
Low-Cost, Multi-Sensor Wireless Platform for SMART Buildings Current wireless sensor Platform: $150-$300/node Sensors Core Components High performance thin films Low temperature integration R2R processing setup Proposed Advanced Sensors Platform: $1-$10/node Active Devices Integrated Circuit and Devices Low temperature electronics Antennas Extensive Capabilities at ORNL Modeling Design Test and Measurements Energy Harvesting 6 Managed by UT-Battelle Technology Impact Market Potential: Not just an improvement over existing technology Prospects of New market, Enhanced Functionality DOE Interests Buildings technology program (BTP), Advanced manufacturing office (AMO) Energy Management Technologies Extensive know-how at ORNL Resources required to target low temperature material/device development
Flexible and Printed Electronic Technology Layer Thickness Control (µm) Material Innovations to Manufacturing Technology ORNL s R&D Platform Materials Device Integration Printing Technology Test & Measurements 10 3 10 2 10 1 Path Towards Hybrid integration Lithography Photo X-ray Ion-beam Electron beam Nanoimprint Screen Inkjet Gravure Flexography Aerosol CMOS Printing Techniques Additive Manufacturing Selective laser/e-beam melting Stereolithography Fused deposition modeling Electron beam Polyjet Hydraulic Hand 1 10 10 2 10 3 Minimum Line Width (µm) 7 Managed by UT-Battelle
Additive Integration Approaches Substrate Integration Bulk Material Discrete Devices Functional Materials & Devices Thick Films Thin Films Nanoparticles Integrated Devices Demands on Material Performance do not change significantly Si: CMOS Glass: Transparent Electronics Plastic: Low-cost Electronics T<1000 C T<600 C T<200 C 3D Structures: Free-form http://www.plasticstoday.com Technology Challenge: Decouple Material and Device 8 Managed by UT-Battelle for the U.S. Department Performance of Energy from Integration Scheme
Flexible Electronics Manufacturing: Annealing Technology T ( C) Photonic Curing of printed circuits on paper and polymers 10-7 10-3 10 0 >10 2 Unique Pulse Thermal Processing Low Temperature Photonic Curing Time (s) PulseForge 3300 Vortek-300 Vortek-500 Sinter with Pulse Thermal Processing Pulse Forge 3300 9 Managed by UT-Battelle Power Density: >20KW/cm 2 Process Window: µs-milliseconds-continuous
Low-Cost, Multi-Sensor Wireless Platform for SMART Buildings Current wireless sensor Platform: $150-$300/node Sensors Core Components High performance thin films Low temperature integration R2R processing setup Proposed Advanced Sensors Platform: $1-$10/node Active Devices Integrated Circuit and Devices Low temperature electronics Antennas Extensive Capabilities at ORNL Modeling Design Test and Measurements Energy Harvesting 10 Managed by UT-Battelle Technology Impact Market Potential: Not just an improvement over existing technology Prospects of New market, Enhanced Functionality DOE Interests Buildings technology program (BTP), Advanced manufacturing office (AMO) Energy Management Technologies Extensive know-how at ORNL Resources required to target low temperature material/device development
Resistance (W) Rsh (W/Sq.) Printed Metal Line Definition and Performance Inkjet Printing of Ag 1 Level:100% Jetting Waveform 2 3.456µs Slew Rate: 2.00 Level:0% 1 Fluid chamber at maximum volume 2 Main drop ejection phase 3 Recovery phase Line width control below 100µm established (Path towards 25µm) Circuit on Paper 3 Printed Metal Performance 10 8 6 4 2 0 Inkjet Printing: Ag/PI (Annealing Time 15minutes) Approaching Bulk Conductivity 2.0 1.5 1.0 0.5 0.0 50 100 150 200 250 300 350 Annealing Temperature ( C) Printed Metal Conductivity approaches the Bulk value R Rsh Additive Integration on Paper, Plastic, Ceramic, and Rubber 11 Managed by UT-Battelle IDE on Plastic
Printed Metal Line Definition and Performance Printed Strain Gauge Performance Strain Gauge on Stretchable Substrates 2.5 Inkjet Printed Strain Gage: Gage Factor 2.0 Flexible Sensor (ΔR/R) % 1.5 1.0 0.5 3D Integration: Strain Gauge on ABS GF for metallic foils are typically between 2-5. 0.0 0.0 0.2 0.4 0.6 0.8 1.0 ε (%) Mechanical Integrity: Gauge Factor comparable to Metallic Foils 12 Managed by UT-Battelle
Multi-Sensor Integration and Performance Evaluation Resistance (W) Capacitance (pf) Temperature Sensor Discrete T and RH Sensors 250 225 Inkjet Printed Capacitive RH Sensor Printed Capacitive RH Sensor Sensitivity: 0.50pF/%RH (a) RH Sensor 200 Performance matching commercial Honeywell Sensor 175 150 40 50 60 70 80 90 100 Relative Humidity (%) Inkjet Printed Resistive Temperature Sensor 200 Printed Temperature Sensor (b) 175 150 125 100 75 Sensitivity: 50 1.02 10-3 / C 25 0 13 Managed by UT-Battelle for the U.S. Department 0 of 10Energy 20 30 40 50 60 70 80 90 100 Temperature ( C) LC Resonant Sensor Multi-sensor Printing and Calibration for system level integration underway
PVDF for Low Temperature Electronics Occupancy Sensor Low-cost, low-power pyroelectric sensor arrays for full scene images Small size, cost effective 16X4 pixel, thermal array 14 Managed by UT-Battelle
Flexible Gas Sensor Development Metal Oxide Sensor Carbon Nano-Tubes (CNT) Printed CNT Line on Plastic Substrate CNT Resistor CNT Sensor Flexible Substrate Inkjet Printed CNT 15 Managed by UT-Battelle
Metal Oxide Sensor Development UV Detector: ZnO/PI Crystalline ZnO Films at Room Temperature Grain Growth on Plastic substrate exploiting Pulse Thermal Processing Technology 16 Managed by UT-Battelle Path Towards Low Temperature Gas Sensor development
Flexible Printed Electronics Technology: Initial TFT Development Focus TFT Design: Basic Element S Flexible Substrate D Initial Target: Mid-Mobility TFTs Semiconductor: IGZSO Dielectric: SiN x, ZrO 2 Metal (G,S,D): Cr, Ag Plastic: PET, Polyimide I DS (A) 10-2 10-3 Id1(Vg=0.1V) Id2(Vg=5.1V) 10-4 Id3(Vg=10.1V) Ig1(Vd=0.1V) 10-5 Ig2(Vd=5.1V) Ig3(Vd=10.1V) 10-6 10-7 10-8 10-9 10-10 10-11 10-12 10-13 10-14 10-15 -10 0 10 V GS (V) Parameter Mobility V th 2.0V SS I ON/OFF Flexible TFT Value 5.5 cm 2 /Vs 0.16 V/decade 4.7E+08 0.1 1 10 1 10 2 10 3 10 4 S BG TFT D Polymers a-si, AOS Si, GaAs, GaN, CNT, Graphene Mobility (cm 2 /V-s) Low Cost, Low Temperature: Unique aspects of TFT electronics 17 Managed by UT-Battelle IGZO SiNx Cr PET Substrate Low Temperature Integration of Functional Circuits
Printable Antenna Development Printable, flexible antennas for operation in ISM frequency bands H + Antenna Design: 433 MHz - Shorting Inverted F design Pin Dimensions 16 by 27 mm Better than 10 db return loss over 5 MHz L Ground Plane Feed (Source) Antenna Design: 2.45 GHz Printed High Frequency Monopole Antenna Return loss below -10dB easily achieved Addressing demands for small size, ease of fabrication, tunability, and low cost for short-range applications. Antenna on Paper Path towards Low Cost, Ultrawideband Antenna Technology RECTENNA Design: Exploring Rectennas for RF Energy Harvesting 18 Managed by UT-Battelle
Energy Harvesting Technologies Organic Photovoltaic Device 20 Current Density (ma/cm 2 ) 15 10 5 J SC = 14.1 ma/cm2 V OC = 0.7 V FF = 64% PCE = 6.3% 0 0.4 0.2 0.0-0.2-0.4-0.6-0.8-1.0 Voltage (V) Device Performance Efficiency (h) 6.3% Fill Factor (FF) 64% Short Circuit Current Density (J sc ) 14.1 ma/cm 2 19 Managed by UT-Battelle Open Circuit Voltage (V oc ) 0.7 V ORNL platform ~3-5mA per Tx 433MHz, 1-5mW P out Rx sensitivity: -140dBm CDMA, CSK Processing gain: ~30dB (1023)
Low Temperature ITO Thin Films: Pulsed DC Sputtering Power (W) Pressure (mtorr) Dep-Rate (Å/s) Resistivity (W-cm) 150 10 0.50 2.94E-03 150 5 0.63 1.26E-03 200 5 1.03 1.86E-03 20 Managed by UT-Battelle Pulse Thermal Processing: 0.16 KW/cm 2 /10Pulses
Energy Harvesting Technologies Hybrid PV Development Small Form Factor Li-polymer Battery: Pouch Cell Voltage profile Structure: FTO/TiOx/Perovskite/Spiro-OMeTAD/Ag FTO/PEDOT:PSS/Perovskite/PCBM/BCP/Al 5 4.5 4 Disharge Charge Voltage (V) 3.5 3 2.5 2 0 2 4 6 8 10 12 Capacity (mah) PCE (Max): 7.0% PCE (Average): 5.5% The pouch cell offers a simple, flexible and lightweight solution to battery design. The pouch cell achieves a 90 to 95 percent packaging efficiency: Highest among battery packs 21 Managed by UT-Battelle
R&D Challenges and Direction Key Drivers: Modeling (Novel concepts, Materials Engineering) Integration possibilities must be considered to set realistic targets High Performance Devices (niche applications) High Cost/Performance Devices (Plastic electronics, R2R manufacturing) 22 Managed by UT-Battelle