Hybrid Analytical–Monte Carlo Model of In/GaAs(001) Droplet Epitaxy: Theory and Experiment

Abstract

We study the droplet epitaxy of indium on the As‐stabilized GaAs(001) substrate using the analytical theory of nucleation combined with kinetic Monte Carlo simulations. The developed model allows considering the atomistic processes of nucleation and growth of droplets without strict binding to the zinc blende structure. We assume that the formation of stable droplets results from the alternation of the processes of assembly and disassembly of subcritical islands. We use a concept of nonmonotonic dynamics of critical size and supersaturation to explain the physical processes on the surface. The thickness of the indium wetting layer exceeds a value of one monolayer and increases gradually with decreasing temperature, which is due to the long‐range interaction of indium with the GaAs substrate. The simulation results are in good agreement with the experiments in a wide range of growth temperatures.

Gillespie-Driven kinetic Monte Carlo Algorithms to Model Events for Bulk or Solution (Bio)Chemical Systems Containing Elemental and Distributed Species

“…For example, this method has been applied to simulate copper electrodeposition 199 (also using τ-leaping) and droplet nucleation. 200 In biological systems, it has been used to model the HIV-1 transactivation network. 201 For chemical systems, the field of PRE has undoubtedly been fruitful in the application of hybrid methods.…”

“…Another kind of acceleration method is the hybrid method, which combines the low computational times of analytical methods or basic deterministic solvers with the high detail in molecular structure as achievable through kMC modeling. For example, this method has been applied to simulate copper electrodeposition (also using τ-leaping) and droplet nucleation . In biological systems, it has been used to model the HIV-1 transactivation network .…”

“…66,67 These advances in computer science in the last decades favored the use of kMC modeling beyond basic chemical systems with, e.g., only a dozen of (reaction) event types or so-called MC (reaction) channels. The increase in processing speed allowed to apply kMC modeling already to complex systems that are influenced by many chemical species (e.g., thousands to millions) and more reactions (e.g., 200) than deterministically accessible with a very high degree of molecular detail. 68−73 One of the main areas of application for kMC modeling involving distributed systems is PRE, which is the main application field in the present contribution, although also examples from other fields such as the biological one are included.…”

Independent Control Over Size and Surface Density of Droplet Epitaxial Nanostructures Using Ultra-Low Arsenic Fluxes

“…After the buffer layer growth, the substrate was cooled down to a deposition temperature of 300 °C with the valve fully closed. The choice of this deposition temperature was associated with the surface density of droplets observed after In deposition at this temperature (10 8 cm −2 or less) [ 24 , 27 , 48 ]. At this density, the distance between droplets is more than 1 µm, which is convenient for the separation of quantum structures.…”

Resistive Switching of GaAs Oxide Nanostructures

“…After the chemical etching of ONSs, formed on the surface of GaAs epitaxial structure by the LAO method, it is possible to create profiled nanoscale structures (PNSs) as a centers for localizing quantum dots growth [35][36][37][38], nanowires [39,40], and also antilattices used in the development of the element base of quantum computers [41]. For the manufacture of such structures, it is necessary to form ONS and then PNS on the GaAs surface with specified geometric parameters.…”