1 / 18

OLED Fabrication

OLED Fabrication. Nesibe Lakhani EECS 277A Prof. Richard Nelson. OLED Structure. OLEDs are light emitting devices that have a thin film of organic compounds as its emissive electroluminescent layer. . Fabrication Methods. Physical Vapor Deposition Screen Printing Ink Jet Printing

adriana
Download Presentation

OLED Fabrication

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. OLED Fabrication NesibeLakhani EECS 277A Prof. Richard Nelson

  2. OLED Structure • OLEDs are light emitting devices that have a thin film of organic compounds as its emissive electroluminescent layer.

  3. Fabrication Methods • Physical Vapor Deposition • Screen Printing • Ink Jet Printing • In-line Fabrication

  4. OLED Fabrication Steps

  5. Physical Vapor Deposition (PVD)

  6. Physical Vapor Deposition • Thermal vapor evaporation of small molecules occurs in environment of 10e(-6) Torr or higher • It is usually carried out on glass substrate • Multicolor displays are made using properly matched shadow masks for depositing RGB emitting materials

  7. Advantages of PVD • Thickness can be easily controlled • 2-dimensional combinatorial arrays of OLEDs can be easily fabricated in a single deposition procedure • PVD uses the generally available vacuum equipment that exists in the semiconductor industry

  8. Disadvantages of PVD • Expensive • Not flexible • Has no control to direct the materials to deposit on the desired areas • Inefficient use of materials

  9. Screen Printing • Used in low information content displays such as logos and signs • Thin films achieved • Elements of screen printing: screen, stencil, squeegee, ink, press bed, and substrate • Mesh materials can vary from polyester to stainless steel

  10. Screen Printing Steps • The mesh material is stretched across a frame • Hole transport layer prepared using a solution of diamine, polycarbonate, and rubrene. • Squeegee is used to wipe solution through the open mesh • Resulting film covers entire surface of ITO • Electron transport layer (ETL) and cathode aredeposited by PVD

  11. Screen Printing • For patterned hole transport layer (HTL) devices: cathode is deposited in a block larger than the HTL pattern • For non-patterned HTL: cathode is deposited through a mask to create emitting regions of known area for device output measurement

  12. Advantages of Screen Printing • Simple • Lower cost • Great reduction in materials usage because materials are only directed to the printed areas • Faster than inkjet printing • More versatile

  13. Ink Jet Printing • OLEDs are sprayed onto substrates like ink sprayed on paper during printing • Advantages: • Reduced cost • Allows OLEDs to be printed on very large films

  14. Ink Jet Printing Ink jet printing to define and pattern RGB emitting subpixels

  15. In-Line Fabrication • Mass production technique • Vertical in-line tool operates with continuous substrate flow • Linear sources of depositing organic and metallic materials

  16. In-Line Fabrication • Cheaper mass production technique • Excellent thickness homogeneity • Excellent deposition stability • Complicated stack structures possible • High deposition rates/high throughput • High material usage • Large substrate handling

  17. OLED Fabrication Roadmap

  18. References • Ghassan E. Jabbour et al., Screen Printing for the Fabrication of Organic Light-Emitting Devices, IEEE 7:5, 2001 • Joseph Shinar, Organic Light-emitting Devices. • http://www.ewh.ieee.org/soc/cpmt/presentations/cpmt0401a.pdf • http://www.opera2015.org/deliverables/MONA_CD-ROM/4_Symposium%20Presentations/04-scholles2752.pdf • Muhamad Mat Salleh, et.al., Fabrication of Organic Light Emitting Diodes. • http://optics.org/cws/article/research/24299

More Related