Assessment of some crystallographic, electrical and optical properties of MOVPE-grown GaInAs(P)/InP heterostructures

Some characterisation results for Ga x In 1-x As y P 1-y /InP heterostructures grown by atmospheric pressure MOVPE are presented. Hall effect, double-crystal X-ray diffraction, low-temperature photoluminescence and Shubnikov-de Haas effect were used. Very high mobilities in GaInAs/InP heterostructures have been recorded: 10750, 92000 and 153000 cm 2 V -1 s -1 at 300, 77 and 10 K respectively for a residual doping level of 2*10 15 cm -3 . These record figures have been related to the presence of a two-dimensional electron gas which is shown to have two populated sub-bands with a total sheet density of n s =2.9*10 11 cm -2 and a mobility of 250000 cm 2 V -1 s -1 at 2.17 K. GaInAsP has also been grown with a low residual doping level (3.5*10 15 cm -3 ) along with high mobilities mu (300 K)=4800 cm 2 V -1 s -1 , mu (77 K)=31000 cm 2 V -1 s -1 . A single photoluminescence line has been recorded at 0.887 eV with a full width at half maximum of 8 meV at 4 K. Finally, the influence of lattice mismatch on GaInAs/InP heterostructures has been investigated: morphology, Hall mobility and electrical properties were studied. In particular, the band gap shift is well interpreted by assuming the breaking of valence band gap degeneracy at k=0 induced by the biaxial strain.