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Comprehensive Experimental and Theoretical Investigation of Electron and Hole Transport Properties through Narrow Constricted Paths with Strained, Lattice Mismatched, Semiconductor Interfaces for Ultrahigh-Frequency Optoelectronic/Electronic Device Applications


Space Vehicles Directorate, RV/Space and Planetary Sciences

RO# Location
13.40.01.B8159 Kirtland Air Force Base, NM 871175776


Name E-mail Phone
Sharma, Ashwani K 505.846.0165


In the nanoscale-regime, the electrons and other quasi-particles, such as holes and excitons, start to behave more like waves than particles. This transition into the quantum mechanical regime does not come about abruptly. Rather, there is a transition region in which bulk properties begin to slowly weaken while the quantum mechanical effects begin to strengthen. However, the effects of quantum confinement on carrier transport properties have been primarily investigated in ternary and quaternary material heterostructures and superlattices, in which scattering is seen to enhance some modes of electron-lattice interaction while suppressing others, thereby changing the relative value of the carrier’s effective masses of electrons and holes, as compared to bulk semiconductors. Studies of quantum confinement and transport in Si and GexSi(1-x) have been very limited. However, as Si based and GexSi(1-x) based active regions of the microelectronic devices are scaled down in all three dimensions to a few nanometers, understanding of the physics, especially electron-hole transport properties, including the role of biaxial strain, in the transition region is of great importance, particularly as it affects the overall band structure. Therefore, carrier-lattice interactions (i.e., strain effects), which includes the reversal splitting of light- and heavy-hole bands, as well as the decrease of conduction-band effective mass by reduced semiconductor bandgap energy to the extent of splitting the valence-band’s relative positions of heavy holes and light holes, as compared to bulk Si and GexSi(1-x), in turn has a direct effect on both electron and hole mobilities, thus the speed and high frequency response of the devices.



Ghatak BKP: Effective Electron Mass in Low-Dimensional Semiconductors. New York: Springer, 2013: 978-3-642-31247-2/0933-033X

Ohta H, Watanabe T, Ohdomari I: Japanese Journal of Applied Physics 46(5B): 3277-3282, 2007


Semiconductor growth; Semiconductor junctions; Lattice mismatch; Interfacial strain; Nanowires; Nanoscaled devices; Nanoelectronics; Semiconductor physics; Semiconductor fabrication;


Citizenship:  Open to U.S. citizens
Level:  Open to Postdoctoral and Senior applicants
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