Conjugated polymers devices

Figure 15-10. Schematic band diagrams for single-layer conjugated polymer devices at various values of forward bias. Forward bias is defined with respect lo ITO.

Comparison of the spectral response and of the power efficiency of these first conjugated polymer/fullerene bilayer devices with single layer pure conjugated polymer devices showed that the large potential of the photoinduced charge transfer of a donor-acceptor system was not fully exploited in the bilayers. The devices still suffer from antibatic behavior as well as from a low power conversion efficiency. However, the diode behavior, i.e. the rectification of these devices, was excellent. 

Fig. 5.1. Charge generation process in a single-layer conjugated polymer device under short-circuit conditions in the MIM model. VB valence band, CB conduction band, Eg bandgap, P+, P positive and negative polarons...

Dhoot AS, Ginger DS, Beljonne D, Shuai Z, Greenham NC (2002) Triplet formation and decay in conjugated polymer devices. Chem Phys Lett 360(3-4) 195-201... 

Bhattacharyya S, Kymakis E, Amaratunga GAJ (2004) Photovoltaic properties of dye functionalized single-wall carbon nanotube/conjugated polymer devices. Chem Mater 16 4819... 

E. Smela, Microfabrication of PPy Microactuators and Other Conjugated Polymer Devices. /. Micromech. Microeng. 1999,9,1-18. 

Smela, E. 1999. Microfabrication of polypyrrole microactuators and other conjugated polymer devices. J Micromech Microeng 9 1. 

A large fraction of the conjugated polymer devices manufactured commercially or in research laboratories today will not function in an environment with water or oxygen, and thus must be protected from ambient atmosphere. This is an acute challenge with OLEDs, which currently seem to be manufacturable, but result in components with insufficient life span. There are, of course, multiple approaches, including varnishes and lamination of plastic foils (tape) over the device. 

Pede, D., E. Smela, T. Johansson, M. Johansson, and O. Inganas. 1998. A general-purpose conjugated-polymer device array for imaging. Adv Mater 10 233. 

Direct or indirect patterning techniques can be used to microfabricate conjugated polymer devices. Indirect patterning is one commonly used technique in microelectronics industry and can be used for conjugated polymer patterning as well. This... 

D. D. C. Bradley, R. H. Friend, P. L. Burn, A, Kraft, and A. B. Holmes, Electroluminescence from multilayer conjugated polymer devices—spatial control of exciton formation and emission, Chem. Phys. Lett. 200 46(1992). 

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