Self-Catalyzed Growth and Characterization of In(As)P Nanowires on InP(111)B Using Metal-Organic Chemical Vapor Deposition.
We report the growth of vertical <111>-oriented InAs x P1-x (0.11 ≤ x ≤ 0.27) nanowires via metal-organic chemical vapor deposition in the presence of indium droplets as catalysts on InP(111)B substrates at 375 °C. Trimethylindium, tertiarybutylphosphine, and tertiarybutylarsine are used as the precursors, corresponding to P/In and As/In molar ratios of 29 and 0.01, respectively. The as-grown nanowire growth morphologies, crystallinity, composition, and optical characteristics are determined using a combination of scanning and transmission electron microscopies, electron diffraction, and X-ray photoelectron, energy dispersive X-ray, and Raman spectroscopies. We find that the InAs x P1-x nanowires are tapered with narrow tops, wider bases, and In-rich In-As alloy tips, characteristic of vapor-liquid-solid process. The wires exhibit a mixture of zinc blende and wurtzite crystal structures and a high density of structural defects such as stacking faults and twins. Our results suggest that the incorporation of As into InP wires decreases with increasing substrate temperature. The Raman spectra obtained from the In(As)P nanowires reveal a red-shift and lower intensity of longitudinal optical mode relative to both InP nanowires and InP(111)B bulk, due to the incorporation of As into the InP matrix.
Department of Materials Science and Engineering, University of California Los Angeles, Los Angeles, California, 90095, USA. jeunghunpark@gmail.com.|Present address: IBM T.J. Watson Research Center, Yorktown Heights, New York, 10598, USA. jeunghunpark@gmail.com.
Jeung Hun
JH
Park
Department of Materials Science and Engineering, University of California Los Angeles, Los Angeles, California, 90095, USA.
Marta
M
Pozuelo
Department of Materials Science and Engineering, University of California Los Angeles, Los Angeles, California, 90095, USA.
Bunga P D
BP
Setiawan
Department of Materials Science and Engineering, Hanbat National University, Daejeon, 305-719, Republic of Korea. choong@hanbat.ac.kr.
Choong-Heui
CH
Chung
In(As,P) nanowires; Metal-organic chemical vapor deposition; Raman spectroscopy; Scanning transmission electron microscopy; Self-catalyst; Vapor-liquid-solid process; X-ray photoelectron spectroscopy