Anomalous As desorption from InAs(100) 2×4

Abstract

Arsenic desorption from the InAs(100) 2×4 surface is investigated through temperature programmed desorption (TPD), isothermal desorption, and reflection high-energy electron diffraction. TPD area analysis indicates that the As coverage, θAs, of the InAs 2×4 structure is 0.7 monolayers. The As TPD spectrum shows two desorption features; a broad tail from 300 to 400 °C and a distinct peak at 430 °C. The 430 °C peak is well described in terms of a first-order-desorption kinetics with a preexponential factor ν of 1.5×1019 s−1. This extremely high ν value explains well the narrow window of optimal molecular beam epitaxy growth conditions for InAs.