Modelling of the composition segregation effect during epitaxial growth of InGaAs quantum well heterostructures

Abstract

Using a Monte Carlo (MC) technique, we performed numerical modelling of the kinetic segregation effect during epitaxial growth of a heterostructure containing an In c Ga 1−c As quantum well (QW) surrounded by two GaAs barriers. The growth occurs in the direction coinciding with or slightly tilted from [0 0 1]. The model of growth kinetics takes into account the effect of pseudomorphic deformation of the underlying atomic layers onto the activation energy of adatom diffusion in the growing monolayer. It influences the surface segregation of In atoms and affects the QW shape. Within the effective mass approximation, the dependence of the lowest electron-hole transition energy on the degree of In/Ga segregation (in turn, depending upon the growth conditions and substrate tilting angle) was calculated. The calculations were performed using the composition profiles obtained from the MC modelling and taking into account the corresponding distribution of the elastic strain. The results show that the segregation effect leads to a considerable blue shift and broadening of the QW photoluminescence (PL) peak which increase for higher growth temperatures and lower values of the total cation flux from the gas phase onto the growing surface. Growth on vicinal substrates leads to a reduction of the PL peak broadening.

Structural and vibrational properties of SnxGe1-x: Modeling and experiments

“…Pseudomorphic strain related to lattice mismatch between a film and a substrate can be described by the theory analogous to that of thermal expansion induced deformations. Non-zero stress components are given by [51]:…”

Проектирование Дизайна Туннельно-Связанных Квантовых Ям Для Создания Модулятора По Схеме Маха--Цендера

“…Профиль элементного состава, измеренный с помощью совокупности методов просвечивающей электронной микроскопии, был сопоставлен с результатами численного моделирования ростового процесса, выполненного с учетом сегрегации In по алгоритму, опубликованному в работе [21]. Установлено качественное и количественное согласие модели с экспериментом (рис.…”

Determination of the critical growth rate and growth temperature for group-III elements segregation using two exchanges Kinetic Model

“…Therefore, to design an optoelectronic device based on the III-V semiconductor structures, it is important to predict the concentration profile of the segregating atom for the different growth parameters such as growth temperature and growth rate. Kinetic Monte Carlo (KMC) 18 and two exchanges Kinetic Model (we call it Kinetic Model) for segregation 3,19,20 are two theoretical models that are widely used to calculate the profile of the segregating atoms. Using KMC, the whole growth processes can be simulated based on the short range surface diffusion of adatoms which exponentially depends on the activation energy for the surface diffusion 18 .…”

“…Kinetic Monte Carlo (KMC) 18 and two exchanges Kinetic Model (we call it Kinetic Model) for segregation 3,19,20 are two theoretical models that are widely used to calculate the profile of the segregating atoms. Using KMC, the whole growth processes can be simulated based on the short range surface diffusion of adatoms which exponentially depends on the activation energy for the surface diffusion 18 . Consequently, the concentration of constituent atoms can be calculated for each monolayer(1 ML = half of the lattice constant) 18 .…”

“…Using KMC, the whole growth processes can be simulated based on the short range surface diffusion of adatoms which exponentially depends on the activation energy for the surface diffusion 18 . Consequently, the concentration of constituent atoms can be calculated for each monolayer(1 ML = half of the lattice constant) 18 . Kinetic Model, on the other hand, is a kinetic thermodynamic model, where the profile of atoms concentrations is calculated based on the probability of the exchange of atoms on the surface with the atoms in the underlying layer 3 .…”