AlSb barrier thicknesses ranging from 5 to 12 monolayers have been mea
sured during growth of InAs/AlSb resonant tunneling structures using t
he photoemission oscillation technique. A plot of peak current density
as a function of both measured and estimated barrier thickness confir
ms that use of the photoemission oscillation technique reduces device
performance variations with respect to the conventional time-based app
roach to layer thickness control. Our growth scheme involves a signifi
cant As background pressure during the AlSb growth which results in in
corporation of As in the barrier layer. We have modeled the effect of
the As incorporation on device properties and find that our measured p
eak current values are consistent with these calculations. (C) 1996 Am
erican Institute of Physics.