Monte Carlo simulations of epitaxial growth: comparison of pulsed laser deposition and molecular beam epitaxy

The influence of epitaxial growth method on surface morphology was explored using a solid-on-solid, rate equation, Monte Carlo simulation whose parameters were chosen to approximate 1=1.Si 001.. In simulations corresponding to molecular beam epitaxy, films of 10 monolayer thickness were deposited with a steady-state flux of 0.25 monolayersrs and an adatom energy of 0.3 eV. In simulations corresponding to pulsed laser deposition, films of 10 monolayer thickness were deposited with a pulsed flux of 0.5 monolayersrpulse and 0.5 pulsesrs and adatom energies ranging from 10 to 135 eV. Surface morphology was characterized using surface images, surface height standard deviations, and height–height correlation functions. In comparison to molecular beam epitaxy, pulsed laser deposition was found to result in smaller surface roughness at substrate temperatures below approximately 4008C and larger surface roughness at higher temperatures. This behavior is attributed to a balance between roughening associated with pulsed deposition and smoothening associated with energetic deposition. q1998 Elsevier Science B.V.