Solid source molecular beam epitaxy of Al-free materials for laser applications

The growth of InGaP(As) layers and multi quantum well structures by solid source molecular beam epitaxy with arsenic and phosphorus valved crackers is reported. Unintentionally doped 2.0 /spl mu/m thick InGaP layers grown on a 0.5 /spl mu/m thick GaAs buffer layer contain a two dimensional electron gas with mobility at 77 K as high as 71 770 cm/sup 2//V-sec at a sheet carrier concentration of 4.2/spl times/10/sup 11/ cm/sup -2/. It is shown that the efficiency of incorporation for Be is equal to that for GaAs, while that for Si is slightly higher in InGaP than in GaAs epitaxial layers. Structures containing compressively-strained InGaPAs multiple quantum wells on GaAs substrates have a high photoluminescence intensity for wavelengths of 840-1000 nm.