Research On Growthsimulation Andphysical Propertiesofsemiconductornano-Ma Terials

The ability of integration of nanoscale functional unit on a single chip has become an important symbol of semiconductor technology development in recent decades. The research of the growth techniques, quantum physics effects and penitential applications in devices of semiconductor nanostructure (quantum dots(QDs), quantum rings(QRs), nanowires(NWs)) become the frontier in condensed matter physics and semiconductor nanotechnology.Supported by the National High Technology Research and Development Program of China (Grant No.2009AA03Z405), the National Natural Science Foundation of China (Grant No.60644004), this dissertation focuses on the theoretical simulation on self-organization growth mechanism of semiconductor QDs and QRs,as well as the physical characteristics of semiconductor QDs inthedevice integrations. This thesis covers the following six main contributions:1Three-dimensional kinetic Monte Carlo (KMC) simulation model of semiconductor quantum dots self-organization growth in the Stanski-Kastanov mode is established. The effects of growth parameters (temperature, deposition rate, growth parameters, growth interruption time) on the quantum dot growth quality (uniformity) are investigated.2The model with structured substrate is developed based on the previously KMC model. Atomic diffusion behavior on structured substrate with different shape single nanohole is studied, and atom is preferred to nucleate on the sidewall of the nanohole. By comparing the results, atom is likely to diffuse into the square nanohole due to the distributionof the atomic steps. The effects of atomic bonding energy on QDs composition distribution is also investigated, difference of the atomic bonding energy effects the mixture of atoms in the islands.3Self-organized growth model based on Kinetic Monte Carlo is established. Through the design of buried conditions (the number of quantum dots, quantum dot semi-height ratio) in substrate, controlling the size and location of the self-organized epitaxial quantum ring is achieved. Besides above, quantum rings molecular can be also achieved.4The impact of the strain compensation layer on size of InAs/GaAs QDs,as well as vertical alignment probability of QDs in neighbor layers, is discussed by using finite element method (FEM). From the view of growth uniformity QDs, optimal concentration and position of strain compensation layer is proposed. Besides above, the engery level and wave function distribution of electron and heavy hole in QDs with strain compensation layer at different location is obtained.5Interaction of semiconductor nano films and substrates is investigated by using finite element method. The relationship between the ratio of the film and substrate thickness and the bending curvature of the substrate is discussed.In order to consider the atomic details, simulation model based on the atomic potential function (APF) method is developed, the geometry of quantum dots and ultra-thin substrate system is optimized with energy minimization method. The different size of pyramid, hemispherical quantum dots and substrate are optimized using the APF method. And the influence of size and shape of QDs on nonlinear bending of the ultra-thin substrate is obtained.6The interaction model of the mechanical force and the quantum dot system is established by finite elements method combining with effective mass approximation theory. Strain, band edge, electron and heavy hole energy level in the InAs/GaAs QDs under mechanical force with various directions is discussed. Our results provide a theoretical basis for tailoring emission wavelength by using the mechanical forceactively.