Growth of High-Quality InP-on-GaAs Quasi-Substrates Using Double Low-Temperature Buffers and Strained Layer Surperlattices by MOCVD

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 ad- justment. 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.