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DS: Dünne Schichten
DS 3: Schichtwachstum: Modellierung
DS 3.3: Vortrag
Montag, 11. März 2002, 14:30–14:45, HS 31
Adatom Density Kinetic Monte Carlo (AD-KMC): a new method for fast growth simulation — •Lorenzo mandreoli and Joerg Neugebauer — Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin-Dahlem
The main approach to perform growth simulations on an atomistic level is kinetic Monte Carlo (KMC). A problem with this method is that the CPU time increases exponentially with the growth temperature, making simulations exceedingly expensive. An analysis of typical KMC runs showed two characteristic time scales: tad which is the characteristic time for an adatom jump and tsurf which is the characteristic time before the surface morphology changes. We have developed a new method, called adatom density KMC (AD-KMC), which eliminates the fast time scale tad. This is achieved by directly calculating adatom ditribution rather than to follow explicitly the trajectory of each adatom like in KMC. Statistical checks were done on AD-KMC to test the method. The density of islands and the island-size distribution as function of temperature and flux showed an excellent agreement with KMC results and nucleation theory. Finally, we apply the method to study complex systems such as self-organization in V-grooves and lateral overgrowth.