We report on the effects of hydrogenation of InSb/GaAs epilayers. The
as-grown MOCVD InSb is p-type with an acceptor activation energy of 16
meV. The 16 meV impurity, however, is fully passivated during protona
tion in a hydrogen microwave plasma, revealing a shallower, 2 meV acce
ptor which appears unaffected by further processing. The material rema
ins p-type after hydrogenation and the Fermi level calculations reveal
that the majority carriers over the entire temperature range are hole
s. The electron to hole mobility ratio is sufficiently large however,
that the Hall data shows evidence for an apparent type conversion.