Catalyst-free selective-area MOVPE of semiconductor nanowires on (111)B oriented substrates

Abstract

We report on a catalyst-free approach for the growth of semiconductor nanowires which is attracting interest as building blocks for nanoscale electronics and circuits. Our approach is based on selective-area MOVPE and nanowires are grown from small circular openings of SiO 2 mask defined on (111)B-oriented substrates. At optimized conditions, extremely uniform array of GaAs and InGaAs nanowires with diameter of about 200 nm was grown on GaAs and InP substrates, respectively. The nanowires have hexagonal cross-section and are perpendicular to the substrates, indicating that they are surrounded by {110} facet sidewalls. By reducing the mask opening size, nanowires with diameter down to 50 nm and length more than 5µm were successfully formed. Photoluminescence and transmission electron microscopy characterization was also carried out. (This article is published in J.

Fabrication and characterization of freestanding GaAs∕AlGaAs core-shell nanowires and AlGaAs nanotubes by using selective-area metalorganic vapor phase epitaxy

“…[12][13][14] Since it is a catalyst-free approach and only relies on the thermal decomposition of source materials, high crystalline quality, as well as precise controllability of the epitaxial growth can be expected. Atomic-scale abruptness in doping profiles and heterojunctions along the growth direction ͑vertical heterostructures͒ can be achieved.…”

Characterization of Fabry-Pérot microcavity modes in GaAs nanowires fabricated by selective-area metal organic vapor phase epitaxy

“…We recently proposed and demonstrated an alternative method of preparing semiconductor nanowires by using selective-area metal organic vapor phase epitaxy ͑SA-MOVPE͒. [5][6][7][8] Compared to the conventional vapor-liquid-solid growth, 9,10 this is a catalyst-free approach and only relies on the thermal decomposition of source materials. Furthermore, since this method fully utilizes the nature of epitaxial growth, it is expected to exhibit superior crystalline quality as well as good controllability of the growth with atomic precision to form abrupt doping profiles and heterojunctions, including vertical and lateral heterostructures.…”

MBE Growth of GaAs Whiskers on Si Nanowires

“…III-V NWs on Si substrates have been grown using a catalyst and "catalyst-free" in a wide range of growth pressures and techniques, including metal-organic vapor phase epitaxy (MOVPE), chemical beam epitaxy (CBE), and molecular beam epitaxy (MBE) [1][2][3][4][5]. However, the growth of III-V NWs on Si NWs was only reported recently using MOVPE with a Au catalyst to produce an axial Si:III-V NW [6].…”

“…"Catalyst-free" growth, utilizes group III rich conditions to grown on Si substrates [2,5]. Despite the possible surface and material contamination from the catalyst, NW growth with catalysts still have several advantages: growth can be interrupted and restarted, group III and group V alloys are possible, NW diameter is tailorable, and this can be combined to form double heterostructures and superlattices in the axial growth direction.…”