METAL ORGANIC MOLECULAR-BEAM EPITAXY OF GAAS AND GA0.5IN0.5P

High-quality GaAs/Ga0.5In0.5P heterostructures have been grown by metal-organic molecular beam epitaxy, using both triethylgallium and trimethylindium as group III element sources and arsine and phosphine as group V element sources. Both hydride and hydrogen flow rates have been found to have a significant effect on the growth rate of the layers. GaAs bulk layers show p-type conductivity with carbon as a residual impurity. Minimum carbon incorporation is found at around 500-degrees-C. The purity of the epilayers is also sensitive to the purity of the organometallic starting material. Ga0.5In0.5P bulk layers show optimum structural properties at a growth temperature of 520-degrees-C. Full width at half maximum of GaInP (400) reflection peaks as low as 15" have been found. GaAs/Ga0.5In0.5P multiquantum well structures with wells as thin as 10 angstrom and confinement energy exceeding 300 meV have also been grown.