Arsenic pressure dependence of surface migration length of As{sub}4 molecules during molecular beam epitaxy of GaAsP on (411)A GaAs substrate

摘要

Study of the surface migration length of As{sub}4 molecules during molecular beam epitaxy (MBE) of GaAs under various growth conditions is very important to understand growth mechanism of MBE. Recently; we reported that the surface migration length of As{sub}4 molecules strongly depends on the substrate orientation and is much longer (10～30 μm) than that of Ga atoms (≈1 μm). [1 ,2] The migration length of As{sub}4 molecules on the (411)A substrate,λ{sub}((411)A), changes as exp( -Ea/k{sub}BT) with a small activation energy of Ea = 0.2 eV. In this work, we investigated the arsenic pressure dependence of λ{sub}((411)A) for the first time, and found that λ{sub}((411)A) is strongly dependent on the arsenic (As{sub}4) pressure (P{sub}(As{sub}4).