Charge transporting layer

Most of the known charge-transport layers are -type or hole transporting. Thus this type of layered photoconductor must be charged negatively. 

Multilayer Devices The Incorporation of Charge-Transporting Layers... 

Refining the Properties of PPV - Multilayer Devices 13 Multilayer Devices The Incorporation of Charge-Transporting Layers 14... 

A key feature of our polyphenylene dendrimers is that they can be planarized and thus reduced in dimensionality by intramolecular dehydrogenation [29,35]. This results in large, fused polycyclic aromatic hydrocarbons (PAHs). PAHs serve as structurally distinct, two-dimensional subunits of graphite and show attractive properties such as high charge carrier mobility, liquid crystallinity, and a high thermal stability, which qualifies these materials as vectorial charge transport layers [81]. 

Spojkman M, Mathijssen SGJ, Smits ECP, Kemerink M, Blom PWM, de Leeuw DM (2010) Monolayer dual gate transistors with a single charge transport layer. Appl Phys Lett 96 143304... 

The photoconductivity of polysilanes was described in Section 5.8, and their electroluminescence is covered in Section 5.9.2. These properties make polysilanes possible components of polymer light-emitting diodes, either as charge transport layers or as the actual emissive materials.146 A drawback of the polysilanes is their photodegradation under ultraviolet irradiation, a problem which must be overcome if polysilanes are to become commercially useful. 

A further potential problem associated with the practical fabrication of multilayer OLEDs with low-molar-mass calamitic and columnar liquid crystals with a charge-transport layer, especially as the HTL, is the fluid nature of the liquid crystalline state. This could permit contamination of the columnar liquid crystal during the deposition of subsequent layers by the process of vapour deposition or spin-coating. The columnar materials could well be soluble in the solvent used to deposit the next layer. This would lead to chemical contamination of the individual layers due to mixing of one component into another, the... 

CTL - charge transport layer. Reprinted with permission from Pai and Springett (1993). Copyright 1993 by the American Physical Society, (b) Surface potential during a photo-induced-discharge curve measurement. Reprinted with permission from Law (1993). Copyright 1993 American Chemical Society, (c) PIDC and contrast for a dual layer photoreceptor. Reprinted from Borsenberger and Weiss (1998) by courtesy of Marcel Dekker, Inc. 

The rate at which the electric field decays will be determined by the rate at which free electrons and holes are generated, provided that the transit time of holes through the transport layer is shorter than the exposure time. The decay will be linear if the intensity of illumination is constant, the efficiency of carrier generation is independent of the electric field and no charge is trapped in the charge transport layer. If there are deep traps with long escape times within the layer, then there will be a residual potential, VR, at the end of the discharge. 

Charge Transport Layer Charge Generation Layer... 

Charge transport in a practical charge transport layer (CTL) must satisfy two basic requirements. First, charge carriers must be mobile enough to cross the CTL in the time available. We will focus on this aspect. Second, deep trapping (such that the... 

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