Ws. Han et al., ORDERING EFFECT ON BAND-GAP LOWERING IN LATTICE-MATCHED INALAS EPILAYERS GROWN ON INP BY METAL-ORGANIC CHEMICAL-VAPOR-DEPOSITION, Applied physics letters, 72(15), 1998, pp. 1905-1907
Band-gap lowering due only to the cation ordering effect is investigat
ed in InAlAs layers grown on InP by using photoluminescence measuremen
t. Double-crystal x-ray diffraction and Rutherford backscattering meas
urements confirm that both of the InAlAs epilayers studied, grown at 7
00 and 750 degrees C, are lattice matched with InP substrates. Through
transmission electron diffraction measurements, it is observed that a
CuPt-type ordering structure is formed in the InAlAs layers grown at
700 degrees C but not in the layers at 750 degrees C. Photoluminescenc
e measurements at 1.7 K reveal that the band-gap energy of the ordered
InAlAs is smaller by 60 meV than that of the unordered InAlAs. (C) 19
98 American Institute of Physics.