ABSTRACT
Shinjiroh Hara*, Junichi Motohisa, Jinichiro Noborisaka, Junichiro Takeda and Takashi Fukui Graduate School of Information Science and Technology, and Research Center for Integrated Quantum Electronics, Hokkaido University, North 14 West 9, Sapporo 060-0814, Japan * hara@rciqe.hokudai.ac.jp
Abstract We demonstrate formation of nano-wires with GalnAs/GaAs double hetero-structures using selective area metal-organic vapor phase epitaxy (SA-MOVPE) on SiC>2 masked GaAs (111) B substrates with periodic circular openings. Hexagonal nano-wires with six vertical {110} sidewall facets and a lateral size of around 70 to 260 nm are successfully fabricated on the masked GaAs (111) B substrates. Using microscopic area photoluminescence (p-PL) measurements, PL emission from single GalnAs/GaAs double hetero-structure nano-wires is clearly identified at energy of around 1.28 eV. Full width at half maximum (FWHM) of the PL emission spectra from nano-wires is as narrow as around 10 meV. 1
1. Introduction Nano-structures, such as carbon nano-tubes and semiconductor nano-wires, have been intensively investigated because of their enormous potential for new functional electronic and photonic device applications in the next generation. As a new technique to realize ultra small logic circuits [1], lasers [2], photo-detectors [3] and field effect transistors [4], semiconductor nano-wires have been intensively studied in recent years, and nano-wire superlattice (or hetero-) structures have been demonstrated for further electronic and photonic device applications. [5, 6] So far, almost all of the semiconductor nano-wires have been fabricated by vapor-liquid-solid (VLS) growth [7] or chemical vapor deposition (CVD) with metal catalysts, such as gold (Au) particles. However, these growth techniques with metal catalysts substantially have a poor controllability of positioning and size uniformity of nano-wires because it depends on the position and size of metal particles randomly deposited on semiconductor substrates. In previous studies, we have proposed and demonstrated a novel fabrication technique for semiconductor nano-wire arrays by using selective area metal-organic vapor phase epitaxy (SA-MOVPE) on partially masked semiconductor substrates without any small particles of metal catalysts. [8 - 10] SA-MOVPE is very promising epitaxial growth techniques for fabricating not only nano-wires but also other nano-structures, e.g. quantum dots [11], photonic crystals [12, 13] and two-dimensional artificial Kagome lattices [14], because we can expect better controllability for crystal quality, abruptness of hetero-structure interfaces, doping as well as positioning and size uniformity of nano-structures. In this paper, we report on successful fabrication of GalnAs/GaAs
double hetero-structure nano-wires with well defined vertical facets by utilizing SA-MOVPE growth. We also show strong photoluminescence emissions from single nano-wire, which indicate good crystal qualities of nano-wires. These characteristics of double hetero-structure nano-wires are quite important for future applications to ultra small nano-wire light emitters and single photon emitters.
