KAUST DepartmentPhysical Sciences and Engineering (PSE) Division
Computational Physics and Materials Science (CPMS)
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AbstractCharge transfer predicted by standard models is at odds with Pauling’s electronegativities but can be reconciled by the introduction of a cluster formation model [Schwingenschlögl et al., Appl. Phys. Lett. 96, 242107 (2010)]. Using electronic structure calculations, we investigate p- and n-type doping in silicon and diamond in order to facilitate comparison as C has a higher electronegativity compared to Si. All doping conditions considered can be explained in the framework of the cluster formation model. The implications for codoping strategies and dopant-defect interactions are discussed.
CitationSchwingenschlögl U, Chroneos A, Schuster C, Grimes RW (2012) Electronegativity and doping in semiconductors. Journal of Applied Physics 112: 046101. doi:10.1063/1.4747932.
JournalJournal of Applied Physics
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Organic Semiconductors: Rational Design of Organic Semiconductors for Texture Control and Self-Patterning on Halogenated Surfaces (Adv. Funct. Mater. 32/2014)Ward, Jeremy W.; Li, Ruipeng; Obaid, Abdulmalik; Payne, Marcia M.; Smilgies, Detlef-M.; Anthony, John E.; Amassian, Aram; Jurchescu, Oana D. (Wiley-Blackwell, 2014-08)
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Impact of semiconductor/metal interfaces on contact resistance and operating speed of organic thin film transistorsWondmagegn, Wudyalew T.; Satyala, Nikhil T.; Pieper, Ron J.; Quevedo-López, Manuel Angel Quevedo; Gowrisanker, Srinivas; Alshareef, Husam N.; Stiegler, Harvey J.; Gnade, Bruce E. (Springer Nature, 2010-09-24)The contact resistance of field effect transistors based on pentacene and parylene has been investigated by experimental and numerical analysis. The device simulation was performed using finite element two-dimensional drift-diffusion simulation taking into account field-dependent mobility, interface/bulk trap states and fixed charge density at the organic/insulator interface. The width-normalized contact resistance extracted from simulation which included an interface dipole layer between the gold source/drain electrodes and pentacene was 91 kΩcm. However, contact resistance extracted from the simulation, without consideration of interface dipole was 52.4 kΩcm, which is about half of the experimentally extracted 108 kΩcm. This indicates that interface dipoles are critical effects which degrade performances of organic field effect transistors by increasing the contact resistance. Using numerical calculations and circuit simulations, we have predicted a 1 MHz switching frequency for a 1 μm channel length transistor without dipole interface between gold and pentacene. The transistor with dipole interface is predicted, via the same methods, to exhibit an operating frequency of less than 0.5 MHz. © 2010 Springer Science+Business Media LLC.