Associate Professor CHUA Lay Lay

(Assistant Head – Graduate Programmes)




B.Sc. Computational Chemistry, NUS, 1995; Engineer, then Principal  Engineer, Chartered Semiconductor Manufacturing, 1995-2001; Member of Technical Staff, Bell Laboratories, 2001-2002;  Research Associate, Cavendish Laboratory, University of Cambridge, 2002-2003; Research Fellow, ONDL, Physics, NUS, 2004-2008; Ph.D. Physics, University of Cambridge.

Contact Information 

Office: S7-03-12
Tel: (65)-6516-4834 | Fax: (65)-6779-1691
Email: chmcll@nus.edu.sg | Personal webpage


 

Recognition and Achievements

  • Inaugural Dual University Professorship appointment between NUS and Cambridge (2008)
  • Associate editor for Journal of Materials Chemistry C- Royal Society of Chemistry

Research Interests

My research program focuses on materials and processing development to advance the science and technology of polymer organic semiconductors including organic polymer−graphene or polymer-swcnt hybrids. Several device chemistry aspects that is central to Organic Electronics (light-emitting diodes, solar cells, thermoelectric generators, photodiodes, batteries and sensors, including structure-morphology–property relations and energy-level engineering.

 

Research Highlight

Electrodes with sufficiently low, work functions to match the appropriate band edge of the semiconductor are required in all high performance devices for efficient injection (and/or extraction) of electrons. Ambient processability will confer an added design and manufacturing advantage; but electron contacts with work functions shallower than 4.0 eV are fundamentally incompatible with oxygen and moisture reduction reactions. We recently show that this dilemma can be resolved in an elegant way using di- and higher-valent anions with negative gas-phase electron affinities, such as oxalate, sulfite, carbonate, sulfate and phosphate.

 

Teaching Contributions

  • CM4253 Materials Chemistry 2
  • CM4254 Chemistry of Semiconductors

 

Representative Publications 

  • Kam, F. Y.; Png R. Q.; Ang M. C. Y.; Kumar, P.; Rubi, K.; Mahendiran, R.; Solomeshch, O.; Tessler, N.; Lim, G. K.; Chua, L. L.; Ho, P. K. H. Solution-processed 2-dimensional hole-doped ionic graphene compound, Mater. Horiz. 2017, 4, 456.
  • Seah, W. L.; Tang, C. G.; Png, R. Q.; Keerthi, V.; Zhao, C.; Guo, H.; Yang, J. G.; Zhou, M.; Ho, P. K. H.; Chua, L. L. "Interface doping for ohmic organic semiconductor contacts using self-aligned polyelectrolyte counterion monolayer" Adv. Funct. Mater. 2017, 1606291.
  • Tang, C. G.; Ang, M. C. Y.; Choo, K. K.; Keerthi, V.; Tan, J. K.; Nur Syafiqah, M.; Kugler, T.; Burroughes, J.H.; Png, R. Q.; Chua, L. L.; Ho, P. K. H. "Doped polymer semiconductors with ultrahigh and ultralow work functions for ohmic contacts", Nature  2016, 539, 536.
  • Png, R. Q.; Ang, M. C. Y; Teo, M. H.; Choo, K. K.; Tang, C. G.; Belaineh, D.; Chua, L. L.; Ho, P. K. H. "Madelung and Hubbard interactions in polaron band model of doped organic semiconductors", Nat. Commun.  2016, 7, 11948.
  • Yang, J. G.; Seah, W. L.; Guo, H.; Tan, J. K.; Zhou, M.; Matsubara, R.; Nakamura, N.; Png, R. Q.; Ho, P. K. H.; Chua, L. L. "Characterization of ohmic contacts in polymer organic field-effect transistors", Org. Electron. 2016, 37, 491.