Cross-sectional scanning tunneling microscopy of GaAsSbÕGaAs quantum well structures
نویسندگان
چکیده
We have used cross-sectional scanning tunneling microscopy ~STM! to perform nanometer-scale characterization of compositional structure and interfacial properties within GaAs12xSbx /GaAs double-quantum well structures. An algorithm has been devised based on analysis of strain effects in STM data to obtain detailed, quantitative compositional profiles within alloy layers. Using this and other analysis techniques, we have assessed the influence of group V anion soaks at each heterojunction interface on interface roughness and abruptness. An As soak at the GaAs–on– GaAs12xSbx interfaces reduces interface roughness but leads to a slight loss of abruptness at the interface, while an As1Sb soak at GaAs12xSbx –on–GaAs interfaces improves abruptness while leaving interface roughness largely unaffected. Significant compositional grading at the nanometer scale is observed within the GaAs12xSbx layers. © 2002 American Institute of Physics. @DOI: 10.1063/1.1501740#
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