ANOMALOUS AS DESORPTION FROM INAS(100) 2X4

Arsenic desorption from the InAs(100) 2X4 surface is investigated thro ugh temperature programmed desorption (TPD), isothermal desorption, an d reflection high-energy electron diffraction. TPD area analysis indic ates that the As coverage, theta(As), of the InAs 2X4 structure is 0.7 monolayers. The As TPD spectrum shows two desorption features; a broa d tail from 300 to 400-degrees-C and a distinct peak at 430-degrees-C. The 430-degrees-C peak is well described in terms of a first-order-de sorption kinetics with a preexponential factor nu of 1.5X10(19) s-1. T his extremely high nu value explains well the narrow window of optimal molecular beam epitaxy growth conditions for InAs.