Abstract: We investigate the growth of InP-on-GaAs combined with the advantages of double low-temperature (LT) buffers and strained layer surperlattices (SLSs).It is found that LT-InP/LT-GaAs double LT buffers are more effective for strain accommodation than a LT-InP single buffer in InP-on-GaAs.On the other hand,there is an optimal thickness for LT-GaAs for a given thickness of the LT-InP layer,at which the double LT buffers can reach the best state for strain adjustment.Furthermore,the position of insertion of SLSs should be carefully designed because the distance above the InP/buffer interface plays an important role in threading dislocation interactions for dislocation reduction.As a result,the density of threading dislocations in the InP epilayer is markedly reduced.X-ray diffraction measurements show that the full width at half maximum of the ω/2θ rocking curve for the 2μm-thick InP epilayer is less than 200" .

Key words: InP-on-GaAs, double low-temperature buffers, InGaP/InP SLSs, MOCVD