УДК: 541.64

Optical investigation of photo-bleaching effects in organic Alq3 thin films

Bonfigli, F., Brogioli, D., Vincenti, M.A., Montereali, R.M.

Publication in Journal of Optical Technology

For Russian citation (Opticheskii Zhurnal):

Bonfigli F., Brogioli D., Vincenti M.A., Montereali R.M. Optical investigation of photo-bleaching effects in organic Alq3 thin films [на англ. яз.] // Оптический журнал. 2011. Т. 78. № 7. С. 4–9.

Bonfigli F., Brogioli D., Vincenti M.A., Montereali R.M. Optical investigation of photo-bleaching effects in organic Alq3 thin films [in English] // Opticheskii Zhurnal. 2011. V. 78. № 7. P. 4–9.

For citation (Journal of Optical Technology):

F. Bonfigli, D. Brogioli, M. A. Vincenti, and R. M. Montereali, "Optical investigation of photo-bleaching effects in organic Alq3 thin films," Journal of Optical Technology. 78(7), 419-423 (2011). https://doi.org/10.1364/JOT.78.000419

Abstract:

The photo-bleaching effects of selective ultraviolet and blue light illumination on the photoluminescence spectra of thermally evaporated tris(8-hydroxy-quinoline) aluminum (Alq3) thin films exposed in air were investigated by fluorescence spectroscopy and advanced optical imaging techniques. The photoluminescence intensity time behavior observed in the Alq3 films at different excitation powers allows to establish that Alq3 molecules in their exciting state are involved in these complex phenomena. The photo-bleaching processes were exploited for direct laser patterning of the investigated Alq3 thin films.

Keywords:

organic light-emitting materials, Alq3, photoluminescence, thin films, laser patterning

Acknowledgements:

The authors are indebted with S. Almaviva, G. Baldacchini, B. Kemps, S. Gambino, and E. Nichelatti for useful discussions and support. Research carried out within TECVIM (TECnologie per la Visualizzazione di IMmagine) project, founded by Italian Ministry of University and Scientific Research, MIUR.

OCIS codes: 160.4890, 180.2520, 300.6280, 310.0310, 350.3850

References:

1. Tang C.W., VanSlyke S.A. Organic electroluminescent diodes // Appl. Phys. Lett. 1997. V. 51. № 12. P. 913–915.
2. Sheats J.R., Antoniadis H., Hueschen M., Leonard W., Miller J., Moon R., Roitman D., Stocking A. Organic Electroluminescent Devices // Science. 1996. V. 273. P. 884–888.
3. Kozlov V.G., Bulovic V., Burrows P.E., Forrest S.R. Laser action in organic semiconductor waveguide and double-heterostructure devices // Nature. 1997. V. 389. P. 362–364.
4. Samuel I.D.W., Turnbull G.A. Organic semiconductors lasers // Chem. Rev. 2007. V. 107. P. 1272–1295.
5. Lally C.H., Davies G.J., Jones W.G., Smith N.J.T. UV quantum efficiencies of organic fluors // Nucl. Instr. and Meth. B. 1996. V. 117. P. 421–427.
6. Montereali R.M., Gambino S., Loreti S., Gagliardi S., Pace A., Baldacchini G., Michelotti F. Morphological, Electrical and Optical Properties of Organic Light-Emitting Diodes with a LiF/Al Cathode and an Al-Hydroxyquinoline/Diamine Junction // Synth. Metals. 2004. V. 143. P. 171–174.
7. Aziz H., Popovic Z., Xie S., Hor A.M., Hu N.X., Trip C., Xu G. Humidity-induced crystallization of tris (8-hydroxyquinoline) aluminium layers in organic light-emitting devices // Appl. Phys. Lett. 1998. V. 72. P. 756–758.
8. Chiacchiaretta P., Baldacchini G., Baldacchini T., Pode R.B., Vincenti M.A. Long Time Degradation of Alq3 Thin Films // Proc. 14th Int. Workshop Inorganic and Organic Electroluminescence & 2008 Intern. Conf. Science and Technology of Emissive Displays and Lighting, EL2008. Bagni di Tivoli, Rome, Italy. September 9–12, 2008. P. 305–308.
9. Aziz H., Popovic Z.D., Hu N.X., Hor A.M., Xu G. Degradation mechanism of small molecule-based organic light-emitting devices // Science. 1999. V. 283. P. 1900–1902.
10. Thangaraju K., Amaladass P., Bharati K.S., Mohanakrishan A.K., Narayanan V., Kumar J. Studies on influence of light on fluorescence of tris (8-hydroxyquinoline) aluminium thin films // Appl. Surf. Science. 2009. V. 255. P. 5760–5763.
11. Thangaraju K., Kumar J., Amaladass P., Mohanakrishnan A.K., Narayana V. Study on photoluminescence from tris (8-hydroxyquinoline) aluminium thin films and influence of light // Appl. Phys. Lett. 2006. V. 89. P. 082106.1–082106.3.
12. Rosselli F.P., Quirino W.G., Legnani C., Calil V.L., Teixeira K.C., Leitao A.A., Capaz R.B., Cremona M., Achete C.A. Experimental and theoretical investigation of tris (8-hydroxyquinolinate) aluminium (Alq3) photo degradation // Organic Electronics. 2009. V. 10. P. 1417–1423.
13. Baldacchini G., Gagliardi S., Montereali R.M., Pace A., Pode R.B. Optical spectroscopy of tris (8-hydroxyquinoline) aluminium thin films // Phyl. Mag. B. 2002. V. 82. № 6. P. 669–680.
14. Brinkmann M., Gadret G., Muccini M., Taliani C., Masciocchi N., Sironi A. Correlation between molecular packing and optical properties in different crystalline polymorphs and amorphous thin films of mer-tri(8-hydroxyquinoline) aluminum(III) // Journ. Am. Chem. Soc. 2000. V. 122. P. 5147–5157.