Thin organic semiconductors

ORGANIC SEMICONDUCTOR THIN-FILM TRANSISTOR SENSORS... 

The simplest and most widely used model to explain the response of organic photovoltaic devices under illumination is a metal-insulaior-metal (MIM) tunnel diode [55] with asymmetrical work-function metal electrodes (see Fig. 15-10). In forward bias, holes from the high work-function metal and electrons from the low work-function metal are injected into the organic semiconductor thin film. Because of the asymmetry of the work-functions for the two different metals, forward bias currents are orders of magnitude larger than reverse bias currents at low voltages. The expansion of the current transport model described above to a carrier generation term was not taken into account until now. 

As a class of n-type organic semiconductors, PBI derivatives have received considerable attention for a variety of applications [312, 313], for example, for organic or polymer light-emitting diodes (OLEDs and PLEDs) [314, 315], thin-film organic field-effect transistors (OFETs) [316, 317], solar cells [318, 319], and liquid crystals [320]. They are also interesting candidates for single-molecule device applications, such as sensors [321], molecular wires [322], or transistors [141]. 

Katz, H. Laquindanum, J. 1999. Thin film transistor and organic semiconductor material thereof. V S. Patent 5,936,259. 

Figure 29. For the latter case, it is considered that the semiconducting re-electron systems are separated by insulating hydrocarbon spacers, resulting in alternate thin layers of organic semiconductor and insulator in these monolayer assemblies. The direct current - voltage (I - V) characteristics were mea- sured for the multilayers H2Pc(R)8 and Cu-Pc(R)8 in directions perpendicular and parallel to the film plane. In both cases, the linear I - V relationships of Ohm s law were observed at low electric field and obtained DC conductivities are summarized in Table 3. The normal conductivity (ajJ were ca. 10 13 S cm-1, while the lateral ones p//) were 3.4 x 10-7 and 9.9 x 10 7 S cm 1 for films of the metal-free and copper Pc derivatives, respectively. The former (ojJ tended to decrease slightly with increase of Figure 29. Schematical illustration of the substituent alkyl chain length,...

Klenkler RA, Xu G, Aziz H, Popovic ZD (2006) Charge-carrier mobility in an organic semiconductor thin film measured by photoinduced electroluminescence. Appl Phys Lett 88 242101... 

Kang MJ, Doi 1, Mori H, Miyazaki E, Takimiya K, Ikeda M, Kuwabara H (2011) Alkylated dinaphtho[2,3-b 2, 3 -f]thieno[3,2-b]thiophenes (C -DNTTs) organic semiconductors for high-performance thin-film transistors. Adv Mater 23 1222-1225... 

Rand BP, Burk DP, Forrest SR (2007) Offset energies at organic semiconductor heterojunctions and their infiuence on the open-circuit voltage of thin-film solar cells. Phys Rev B 75 115327... 

Hirai (2) prepared an organic semiconductor layer for an organic thin-film transistor consisting of pentacene derivatives, (II), having a thickness of 1 pm. 

Heteroacene derivatives, (I), were prepared by Park et al. (1), which were effective as organic thin-film transistors. Low-molecular-weight thiophene oligomers were also prepared by Hahn et aL (2) and used as organic semiconductors. 

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