Direct Growth of GaN Nanowires by Ga and N₂ without Catalysis

Abstract

Gallium nitride nanowires (GaN NWs) are commonly synthesized using harsh/toxic conditions (e.g., ultrahigh vacuum, high substrate temperature, toxic materials, etc.) or by catalytic conditions. In this work, GaN NWs were grown on graphite substrates by the direct reaction of Ga atoms with excited N plasma without the need for a catalyst. This was achieved using plasma enhanced chemical vapor deposition (PECVD) under moderate vacuum conditions and temperatures below 900 °C. The GaN NWs consisted of polycrystalline nanostructures that appeared as pyramidal islands, with diameters from 90 to 200 nm and lengths from 4 to 20 μm. A model for the mechanism of nucleation and growth of the GaN NWs is proposed. The morphology and quality of the GaN NWs varied significantly depending on the fabrication parameters that were used. Moreover, they exhibited desirable photoluminescence (PL) and field emission (FE) properties. This method shows great promise for the simple, low cost, and environmentally friendly fabrication of high-purity NWs, which may lead to improved GaN NW-based devices.

Field emission of GaN nanofilms on Si substrates enhanced by hydrogen plasma treatment

“…Clearly, the FN plots present the linear relationships in the high-field regions for all the samples, suggesting that the emission current originates from a quantum mechanical tunneling process. For the typical FN emission, the current density can be described by the following FN equation [27] b f…”

Wrinkled‐Surface‐Induced Memristive Behavior of MoS2 Wrapped GaN Nanowires

“…Figure a illustrates the preparation process diagram of the MoS 2 ‐GaN NWs memristor. The memristive layer in this two‐terminal device is fabricated on the silicon (Si) substrate by plasma enhanced chemical vapor deposition (PECVD) [ 21–23 ] and magnetron sputtering and to obtain a stable top electrode structure, spray coating is performed with the Ag NWs solution. The side‐ and top‐view SEM images of the MoS 2 ‐GaN NWs and pure GaN NWs are depicted in Figure 1b–e showing that MoS 2 is coated around the NWs.…”

A simple method to synthesize worm-like AlN nanowires and its field emission studies*

“…[24] In addition, we have been grown polycrystalline GaN nanowires on graphite by the PECVD without catalyst through using Ga and N 2 as precursors. [25] Moreover, single GaN nanowires have been prepared on Al 2 O 3 substrate by the PECVD without catalyst through using Ga and N 2 as precursors. [26] However, worm-like AlN nanowires with polycrystalline structure are prepared by the PECVD method through using Al and N 2 as precursors, which have rarely been reported in previous researches.…”