Effect of growth-interrupted method on quality of AlGaAs/GaAs multiple quantum wells prepared by MBE
(1.Department of Materials Physics and Chemistry, Harbin Institute of Technology, Harbin 150001, China2.School of M aterials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China)
Abstract: AlGaAs/GaAs multi-quantum well (MQW) was prepared by molecular beam epitaxy(MBE) with growth-interrupted heterointerface (GIH) method and continuous growth (CG) method, respectively. The microstructures of the MQWs were characterized by double-crystal X-ray rocking curve (DCRC) and atomic force microscopy (AFM), and the photoluminescence (PL) properties of the MQWs were also studied. The MQWs grown with GIH method show that higher order satellite peaks of Pendell？sung fringes are observed in DCRC, the roughness of surface is much reduced in AFM, and the full width at half maximum (FWHM) of exciton line is much narrower in PL. The results indicate that the GIH method reduces the monolayer growth step density at the heterointerface due to the migration of surface atoms for a few minutes growth interruption, and substantially improves the quality of AlGaAs/GaAs MQWs.
Key words: AlGaAs/GaAs multi-quantum wells; growth interruption; double-crystal X-ray rocking curve; atomic force microscope; photoluminescence