Effect of substrate orientation on the catalyst-free growth of InP nanowires

Abstract

We report the fabrication of self-catalysed InP nanowires on (111)B, (111)A, (110), and (001) InP substrates. Indium droplets, deposited in situ using metalorganic vapour phase epitaxy, are used as seeds for nanowire growth. The preferential nanowire growth direction is always on (111)B, (111)A, and (110) oriented substrates. On (111)A substrates some initial growth in the [111]A direction is observed before kinking into one of the available directions. The nanowires are optically active at room temperature. On (001) substrates no nanowire growth off the substrate is observed. However, growth still takes place in the two possible equivalent azimuthal directions.

Enhanced luminescence from catalyst-free grown InP nanowires

“…In this study we have concentrated on the surface effects in the optical properties of InP nanowires fabricated using a catalyst-free ͑or self-catalyzed͒ MOVPE technique. 3,7 We show that the state of the nanowire surface significantly affects the photoluminescence emission efficiency and that it should, indeed, be taken into account in basic nanowire characterization and possible optoelectronic and gas sensor applications. Also, these results are direct experimental evidence of the effects predicted recently theoretically by Schmidt.…”

“…In metal organic vapor phase epitaxy ͑MOVPE͒, this is done using previously deposited catalytic metal nanoparticles ͑typically gold͒ 2 or, even better, in situ techniques without any substrate preprocessing. 3,4 These methods have provided an easy access for investigations of the structural, electrical, and optical properties of semiconductor nanowires. Especially properties related to their large surface-to-volume ratio are of great interest for, e.g., sensor applications.…”

“…8 The nanowire samples were fabricated in a horizontal reactor atmospheric pressure MOVPE system using in situ deposited indium droplets as seeds for nanowire growth. 3,7 Nanowires grow vertically on ͑111͒B oriented InP substrates and are freestanding until removed for characterization. Some samples were immersed in 50% hydrofluoric acid ͑HF͒ for 1 min.…”

Two-source coevaporation technique for synthesis of indium phosphide films with controlled composition

“…InP films were also deposited by threetemperature method by Rusu [12] while InP deposited/grown in different nanocrystalline forms (nanoparticles, nano wires, etc.) have been reported by others [13][14][15][16][17][18]. But none of the above methods could effectively ensure large area deposition of InP films and the need of a reliable, low-cost and scalable process technology for synthesis of InP in polycrystalline form is the need of the day to expand the use of this material in different device technologies.…”

Investigation on growth related aspects of catalyst-free InP nanowires grown by metal organic chemical vapor deposition

“…These reveal that the nanowires have a rotational twin structure, which appears as alternate dark and bright contrasts along the length of the nanowires. The rotational twin structure is usually observed in III-V semiconductor nanowires such as InP [9,24,25], GaAs [26], and InAs [27] nanowires. The TED pattern shown in Fig.…”