Page 1

Recent Advances in the Reliability of OTFTs

Patrick Too, Herve Vandekerckhove, Guillaume Fichet, M. James Harding, Michael J. Banach

SPIE – 13th August 2012 San Diego

Outline • Plastic Logic company introduction • Reliability of OTFTs • Challenges on the way from Lab to Fab • Applications of Plastic Logic technology and partnerships

SPIE 2012

August 13th 2012


The Leader in Plastic Electronics  Developed lightest, most durable display

technology available today  Demonstrated scalability in the first and

largest production facility  1-2 year lead over the competition for

flexible backplane technology  A single display has 2.8M uniform and

reliable plastic transistors

SPIE 2012

August 13th 2012


Company History Display technology Development

10+ transistors

100+ transistors

1.2 M transistors

Colour EPD

2.8 M transistors

Research, Process Development & Manufacturing

Cambridge University Cavendish Laboratory Research in organic electronics

2000: Cambridge Technology Center translating research into products

SPIE 2012

2008: Dresden Display Factory First plastic electronics factory in the world

August 13th 2012


R&D and Production Set-Up Technology Transfer Cambridge R&D Prototype Line (14”)

Cambridge R&D Prototype Line    

SPIE 2012

Proof of concepts Highly configurable process New designs in < 1 month 1” Chips to A4 displays

August 13th 2012


Production Set-Up Technology Transfer Dresden Factory (Gen 3.5)

Dresden Gen. 3.5 Factory     

Backplane Manufacturing Qualified volume process Production equipment Fully Automated Handling Process, Equipment, Integration Engineers  Thousands of backplane display modules/week SPIE 2012

August 13th 2012


Electrophoretic Plastic Display

SPIE 2012

August 13th 2012


Reliability of OTFTs

SPIE 2012

August 13th 2012


Stress Test System Setup

Stress card module • Fully Automated electrical test system • Flexibility in the electrical test and stress test profiles • Ability to test in different environmental conditions • Capability to test more than 1800 TFTs per day in Cambridge

SPIE 2012

August 13th 2012


Stress Test Waveform etc

Gate Source

1 Waveform

Large range of stress test waveforms available to mimic OLED and EPD displays driving SPIE 2012

August 13th 2012


OTFTs under video rate (60Hz) stress test 600C annealing

1200C annealing

 Video rate stressing was done at ambient controlled atmosphere  Threshold voltage shift is observed under video rate stress test for low annealing temperature (600C) of the OTFTs  The OTFTs show an improvement in the threshold voltage stability after a 1200C annealing

SPIE 2012

August 13th 2012


Effect of solvents on OTFT stability O-Xylene (B.P=1370C)

Mesitylene (B.P= 1650C)

Tetralin (B.P=2050C)

Phenylcyclohexane (2380C)

All samples are annealed in air and stress tested at ambient controlled temperature SPIE 2012

August 13th 2012


Reliability testing Name



Thermo cycling


Mechanical robustness & CTE mismatch

High Temperature Storage


Advance Humidity Storage


Storage of transport conditions Stability against Moisture ingress

Low Temperature Storage


Storage of transport conditions

Real World Usage


Display use in non accelerated mode

Advance Humidity Operation


Accelerated operation at high humidity

Low Temperature Operation


Accelerated operation at low temperature

Ambient Operation


Accelerated operation at ambient conditions

Solar storage


Solar robustness

Altitude test


Pressure sensitivity

SPIE 2012

August 13th 2012


Challenges on the way from Lab to Fab

SPIE 2012

August 13th 2012


The Manufacturing Challenge It is one thing to show a single display at a tradeshowâ&#x20AC;Ś

...quite another to develop a high yield manufacturing process SPIE 2012

August 13th 2012


Process learning & Development 2008 2009 Thickness mean

Thickness mean

Printing process

Deposition process Thickness mean


SPIE 2012

Thickness mean


August 13th 2012 16


Progress in Plastic Logic display 2008


Defects driven High Quality Display

Equipment / Process driven

SPIE 2012

August 13th 2012


Colour Flexible Displays: Now Available Display size Backplane Grey Levels Pixel pitch Contrast Ratio Thickness Weight Colour NTSC

1” - 10.7” 4 – 16 up to 225ppi 12:1 thin as 130 µm down to 11g Available 2-5%

 Paper-like finish  Excellent readability  Colour gamut high enough to enable distinguishability  Bistable enables long battery life

1280 x 960 Colour Display SPIE 2012

August 13th 2012


Colour Flexible Display

SPIE 2012

August 13th 2012


Other Plastic Logic Technologies Transmissive display

Thin displays

Small displays

SPIE 2012

August 13th 2012


Plastic Logic Technology in Action 1.


2. 1. The worldâ&#x20AC;&#x2DC;s first plastic organic electronics factory 2. The most robust display on the market 3. Plastic Logic display at video rate SPIE 2012

August 13th 2012


Partnerships We are looking for further professional partners to enable future applications and products

Partner areas • Potential users of Plastic Logic display components • Technology providers for sensors • End users for flexible logics • Materials and equipment suppliers to further progress the technology

SPIE 2012

August 13th 2012


Plastic Logic Ltd 34, Cambridge Science Park Cambridge, CB18DG UK Tel.: 01223706038 Email:

SPIE 2012

August 13th 2012


SPIE Optics and Photonics_Plastic Logic_13.08.12  
Read more
Read more
Similar to
Popular now
Just for you