ABSTRACT
This chapter provides both finite element analysis and atomistic simulations to understand the impact of alloying on the formation and shape change of GeSi quantum dots (QDs). A non-uniform composition profile of the alloy in the QD has also been predicted from Monte-Carlo simulations. The chapter investigates the correlation of the shape transition and alloying of Ge(Si)/Si QDs by computational methods and to link the results from these computations to experimental data. A transition from planar growth to 3D island growth has been described by J. Tersoff et al and the islands formed in the process are extensively studied because of their promise as QDs in nano-electronics applications. The non-uniform alloying profile gives rise to a characteristic Maltese cross contrast in plan-view transmission electron microscope. The transmission electron microscopy images can be simulated by calculating the strain field using finite element analysis and calculating the image using the column approximation.
