  It is known in the literature that InGaP alloy synthesized within a certain
range of growth temperature (520 - 720 degree Centrigrade) shows Cu-Pt crystal
ordering. This ordering reduces the band gap energy . It was predicted that the
ordering induced modification of energy levels of InGaP lowers its conduction
band edge, which could change a type I band alignment at a GaAs/InGaP
heterojunction to type II . Here we report the first observation of this
ordering related type I/II transition for a GaAs/InGaP heterojunction by C-V
profiling experiments done at room temperature .
