论文信息 - Formation of Defects in MBE Re-Grown GaAs Films on GaAs/AlGaAs Heterostructures

Formation of Defects in MBE Re-Grown GaAs Films on GaAs/AlGaAs Heterostructures

In the present work, we examine the formation of defects on the sidewall slope in 1 μm - thick GaAs layers regrown on GaAs/AlGaAs heterostructures. Site-specific TEM specimens of sidewall slopes are obtained using focused ion beam combined with lift-out method. TEM analysis shows planar defects, such as stacking faults and microtwins, dislocations and large twinned areas, nucleating on the AlGaAs surfaces. SIMS and EDX reveal an increase in carbon and oxygen at the interface. The defect density increased with Al content exceeding 10 10 cm -2 on Al 0.4 Ga 0.6 As. The defect formation is related to the oxidation of Al-containing surfaces.

[1] Y. Shiraishi,et al. Improvement in Electrical Properties at an n-GaAs/n-GaAs Regrown Interface Using Ammonium Sulfide Treatment , 1998 .

[2] Anupam Madhukar,et al. Focused ion beam assisted chemically etched mesas on GaAs(001) and the nature of subsequent molecular beam epitaxial growth , 1997 .

[3] C. Lavoie,et al. Semiconductor substrate cleaning and surface morphology in molecular beam epitaxy , 1997 .

[4] S. Yau,et al. In situ scanning tunneling microscopy of GaAs(001), (111)A, and (111)B surfaces in sulfuric acid solution , 1996 .

[5] I. Matsuyama,et al. In Situ Fabrication of Buried GaAs/AlGaAs Quantum-Well Mesa-Stripe Structures with Improved Regrown Interfaces , 1995 .

[6] K. Choquette,et al. Interfacial characteristics of AlGaAs after in situ electron cyclotron resonance plasma etching and molecular beam epitaxial regrowth , 1994 .

[7] C. Bulle-lieuwma,et al. Novel scheme for the preparation of transmission electron microscopy specimens with a focused ion beam , 1993 .

[8] M. Melloch,et al. Molecular beam epitaxy regrowth by use of ammonium sulfide chemical treatments , 1990 .

[9] Paul R. Berger,et al. Investigation of the interface region produced by molecular beam epitaxial regrowth , 1989 .

[10] J. P. Harbison,et al. Electronic passivation of GaAs surfaces through the formation of arsenic—sulfur bonds , 1989 .