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Finite Element Analysis of Strain Effects on Electronic and Transport Properties in Quantum Dots and Wires

H. T. Johnson·L. B. Freund·C. D. Akyuz·A. Zaslavsky
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Abstract

Lattice mismatch in layered semiconductor structures with submicron length scales leads to extremely high nonuniform strains. This paper presents a finite element technique for incorporating the effects of the nonuniform strain into an analysis of the electronic properties of SiGe quantum structures. Strain fields are calculated using a standard structural mechanics finite element package and the effects are included as a nonuniform potential directly in the time independent Schrodinger equation; a k-p Hamiltonian is used to model the effects of multiple valence subband coupling. A variational statement of the equation is formulated and solved using the finite element method. This technique is applied to resonant tunneling diode quantum dots and wires; the resulting densities of states confined to the quantum well layers of the devices are compared to experimental current-voltage I(V) curves.

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H. T. Johnson, L. B. Freund, C. D. Akyuz, A. Zaslavsky. 1998-06-02. Finite Element Analysis of Strain Effects on Electronic and Transport Properties in Quantum Dots and Wires. https://doi.org/10.1063/1.368549

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