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Inkjet droplet deposition dynamics into square microcavities for OLEDs manufacturing

  • Lei Zhang
  • Tao Ku
  • Xiaoding Cheng
  • Yan Song
  • Dingyi Zhang
Research Paper
First Online:
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Accepted:
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Abstract

The dynamics of inkjet deposition in square microcavities are investigated utilizing a three-dimensional multi-relaxation-time pseudopotential lattice Boltzmann (LB) model with large density ratios. A geometric scheme is considered within the pseudopotential LBM framework to obtain the desired contact angles. The effects of wettability, density ratios, droplet viscosity and impact velocity are explored to reveal the droplet–microcavity interactions. With the contact angles of microcavity increasing, the physical outcomes including the crown-like shape with a small round dot, circular hollow core, uniform film and convex film are identified and analyzed. At a lower density ratio ρr = 11.6, the surrounding denser gas resists the droplet recoiling flow resulting in an increasing hollow core. The appropriate higher droplet viscosity and decreasing impact velocity are preferred which could eliminate the hollow core in the recoiling phase and accelerate the inkjet deposition process straightforward. The revelation of droplet-microcavity dynamics is beneficial for optimizing inkjet deposition process and fabricating uniform OLEDs panels.

Keywords

Microcavity Inkjet OLEDs Lattice Boltzmann method Multi-relaxation-time Density ratios 
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Notes

Acknowledgements

This research work is supported by the National Key Research and Development Program of China through Grant No. 2017YFB0306401.

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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Shenyang Institute of AutomationChinese Academy of SciencesShenyangChina
  2. 2.University of Chinese Academy of SciencesBeijingChina
  3. 3.Liaoning UniversityShenyangChina

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