Double layer light-emitting diodes

M. Jandke, K. Kreger, P. Strohriegl, A. Relini, R. Rolandi, S. Blumstengel, Polarized Electroluminescence in Double-Layer Light-Emitting Diodes with Perpendicularly Oriented Polymers, Adv. Mater. 13 (2001) 1072. 

Relini, A., Rolandi, R., and Blumstengel, S. (2001) Polarized electroluminescence in double-layer light-emitting diodes with perpendicularly oriented polymers. Adv. Mater., 13,1072. 

Fig. 7. Schematic of light emitting diodes (a) single-layer device (b) single heteiostmctuie (c) double heteiostmctuie.

G. He, M. Pfeiffer, K. Leo, M. Hofmann, J. Birnstock, R. Pudzich, and J. Salbeck, High-efficiency and low-voltage p-i-n electrophosphorescent organic light-emitting diodes with double-emission layers, Appl. Phys. Lett., 85 3911-3913 (2004). 

J.S. Kim, M. Granstrom, R.H. Friend, N. Johansson, W.R. Salaneck, R. Daik, W.J. Feast, and F. Cacialli, Indium-tin oxide treatments for single- and double-layer polymeric light-emitting diodes the relation between the anode physical, chemical, and morphological properties and the device performance, J. Appl. Phys., 84 6859-6870, 1998. 

High-efficiency and low-voltage p-i-n electrophosphorescent organic light-emitting diodes with double-emission layers. Applied Physics Letters, vol. 85, no. 17,3911-3. 

Organic Light-Emitting Diodes with Double Hole Transpwrt Layers by Spin-Coating and Evaporation. Jpn. J. Appl. Phys., Vol. 48, pp. 052103-1 3. 

Li, R Tang, H. Shinar, J. Resto, O. and Weisz, S. Z. 1997. Effects of aquare-gia treatment of indium-tin-oxide substrates on the behavior of double layered organic light-emitting diodes. Appl. Phys. Lett. 70 2741-2743. 

Organic light-emitting diodes (OLEDs) based on thin conjugated polymer films have attracted much interest recently because of their possible application in large-area flat-panel displays [1]. The use of double layer structures employing a hole transport layer (HTL) leads to improved device performance (Fig. 1). 

Li, F., H. Tang, J. Anderegg, and J. Shinar. 1997. Fabrication and electroluminescence of double-layered organic light-emitting diodes with the AI2O3/AI cathode. Appl Phys Lett 70 1233-1235. 

Deep-blue organic light-emitting diodes have been produced that are based on multibranched oligofluorenes with a phosphine oxide centre. A series of these compounds were produced (Scheme 13.27) and the compounds showed excellent thermal stabilities, pronounced photoluminescence efficiencies, and good solution processability. Double-layered non-doped OLEDs based on these materials exhibited highly efficient deep-blue electroluminescence. 

PAR 1 Ic] Park B., Huh Y.H., Park J. et al, Solution-processable double-layered ionic p-i-n organic light-emitting diodes . Journal of the Society for Information Display, vol. 19, no. 4, pp. 342-345, 2011. 

Figure 4.77. Light-emitting diode (LED) structures. Shown are (a) a simple multilayer structure of epitaxial p- and n-type layers, and (b) a double heterostructure with accompanying band diagram, illustrating light emission from the p-type region due to confinement between wide-bandgap surrounding layers.

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