MBE grown III-V strain relaxed buffer layers and superlattices characterized by atomic force microscopy

Technical Report · Mon Nov 01 04:00:00 EST 1993

DOI:https://doi.org/10.2172/10194922· OSTI ID:10194922

Howard, A J; Fritz, I J; Drummond, T J; Olsen, J A; Hammons, B E; Kurtz, S R; Brennan, T M

Using atomic force microscopy (AFM), the authors have investigated the effects of growth temperature and dopant incorporation on the surface morphology of MBE grown graded buffer layers and strained layer superlattices (SLSs) in the InGaAlAs/GaAs and InAsSb/InSb material systems. The AFM results show quantitatively that over the temperature range from 380 to 545 C, graded in{sub x}Al{sub 1{minus}x}As(x = 0.05 {minus} 0.32) buffer layers grown at high temperatures ({approximately}520 C), and graded In{sub x}Ga{sub 1{minus}x}As (x = 0.05 {minus} 0.33) buffer layers and In{sub 0.4}Ga{sub 0.6}As/In{sub 0.26}Al{sub 0.35}Ga{sub 0.39}As SLSs grown at low temperatures ({approximately}400 C) have the lowest RMS roughness. Also, for SLSs InAs{sub 0.21}Sb{sub 0.79}/InSb, undoped layers grown at 470 C were smoother than undoped layers grown at 420 C and Be-doped layers grown at 470 C. These results illustrate the role of surface tension in the growth of strained layer materials near the melting temperature of the InAs{sub x}Sb{sub {minus}x}/InSb superlattice. Nomarski interference and transmission electron microscopies, IR photoluminescence, x-ray diffraction, and photocurrent spectroscopy were also used to evaluate the relative quality of the material but usually, the results were not conclusive.

• Research Organization: Sandia National Labs., Albuquerque, NM (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC04-94AL85000
• OSTI ID: 10194922
• Report Number(s): SAND--93-1126C; CONF-9311104--12; ON: DE94002931; BR: GB0103012
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360601
360606
ALUMINIUM ARSENIDES
ARSENIC COMPOUNDS
DOPED MATERIALS
EXPERIMENTAL DATA
GALLIUM ARSENIDES
HETEROJUNCTIONS
INDIUM ANTIMONIDES
INDIUM ARSENIDES
MICROSCOPY
MOLECULAR BEAM EPITAXY
PHYSICAL PROPERTIES
PREPARATION AND MANUFACTURE
SPECTROSCOPY
SUPERLATTICES
SURFACE PROPERTIES
TEMPERATURE DEPENDENCE
X-RAY DIFFRACTION