Barrier Films for Flexible Electronics

Table of Contents

1. SCOPE

2. INTRODUCTION TO ENCAPSULATION

3. SURFACE SMOOTHNESS - DEFECTS

• 3.1. Important considerations of surface smoothness
• 3.2. Micro Defects
• 3.2.2. Pinholes
• 3.2.3. Smoothness / Cracks-Scratches
• 3.2.4. Nanodefects

4. COMPANIES

• 4.1. Vitex
• 4.2. GE
• 4.3. 3M
• 4.4. CPI
• 4.5. Others
• 4.6. Best performing barriers developed to date

5. BARRIER MEASUREMENTS

• 5.1. The Calcium test
• 5.2. MOCON
• 5.3. Black Spot Analysis
• 5.4. Tritium Test
• 5.5. CEA
• 5.6. 3M
• 5.7. IMRE
• 5.8. Standardization efforts

6. OLED - ORGANIC PV FORECASTS

7. CONCLUSIONS

8. REFERENCES

APPENDIX 1: ATOMIC LAYER DEPOSITION

APPENDIX 2: GLOSSARY

APPENDIX 3: IDTECHEX PUBLICATIONS

TABLES

• 2.1. Water vapor and oxygen transmission rates of various materials.
• 2.2. Requirements of barrier materials
• 3.2. Oxygen transmission rates of polypropylene with various coatings.4, 7
• 4.1. Overview of promising high barrier technologies
• 5.1. Metrics and standards for organic solar cell components42
• 6.1. OLED forecasts for display, billboard & signage and lighting applications
• 6.2. OLED forecasts for non-rigid display, billboard & signage and lighting applications
• 6.3. Percentage of the thin film market share represented by OPV

FIGURES

• 1.1. Examples of flexible OLED displays by SONY and AddVision
• 1.2. Flexible OLED fabricated using IMRE' s high barrier substrate and encapsulation technique44
• 1.3. Flexible Solar Cell developed by Fraunhofer IPMS
• 2.1. Schematic diagrams for encapsulated structures a) conventional b) laminated c) deposited in situ4
• 2.2. Scanning electron micrograph image of a barrier film cross section6
• 3.1. Visual defects of a selection of materials with barrier films highlighted through calcium corrosion test. Optical microscope magnification 10x.44
• 3.2. SEM pictures of the Atmospheric Plasma Glow Discharge deposited silica-like films on polymer substrates. Left: Film with embedded dust particles . Right: uniform film27
• 3.3. OTR as a function of defect density for Al(o), SiOx (٭), and SiNx (■) films. The correlation between defect density and the oxygen transmission rate shown was attributed to pinhole defects4
• 3.4. SEM image of a pinhole defect formed from a dust particle32
• 3.5. Scanning electron microscope image of ITO coated on parylene/polymer film34
• 3.6. The measurement of OLED' s lifetime of SiON/PC/ITO and SiON/parylene/PC/parylene/ITO substrate34
• 4.1. Examples of polymer multi-layer (PML) surface planarization a) OLED cathode separator structure b) high aspect ratio test structure.3, 8
• 4.2. Vitex multilayer deposition process8.
• 4.3. SEM cross section of Vitex Barix material with four dyads.
• 4.4. Optical transmission of Vitex Barix coating8.
• 4.5. Edge seal barrier formation by deposition through shadow masks10.
• 4.6. Three dimensional barrier structure. Polymer is shown in red, and oxide (barrier) shown in blue10.
• 4.7. Schematic of flexible OLED with hybrid encapsulation31
• 4.8. Schematic of cross section of graded barrier coating and complete barrier film structure1.
• 4.9. DuPont Displays technology pipeline
• 4.10. Specifications on WVTR for different applications, as seen by Vitex Systems36
• 4.11. 3M specifications on WVTR and OTR for high barrier applications with stringent requirements 14
• 5.1. 2.25 mm2 area of a 50 nm layer of Ca deposited onto barrier coated PET viewed through the substrate. i. Image after 1632 h of exposure to atmosphere; ii. Image analysis whereby the gray scale of Ca degradation is processed to yield a two-color image with
• 5.2. MOCON' s Aquatran™ Model 138
• 5.3. MOCON' s Aquatran™ schematic38
• 5.4. MOCON' s OX-TRAN® Model 2/1039
• 5.5. Silica induced black spots, letters A & B mark black spots with a centralized black dot (silica particle)32
• 5.6. Black spot formation and growth mechanisms 32
• 5.7. General Atomics HTO WVTR testing apparatus40
• 6.1. Stages of reliability R&D, current status of OPV41
• 7.1. The iRex iLiad and the Amazon Kindle rigid e-book readers
• 7.2. PVI' s flexible electrophoretic display and color electrophoretic display by SAMSUNG LCD, demonstrated at SID 2008