Selective-area growth of vertically oriented GaN nanostructures with a hafnium pre-orienting layer

Fabrication of InxGa1−xN Nanowires on Tantalum Substrates by Vapor-Liquid-Solid Chemical Vapor Deposition

“…The first one is the X A peak from In x Ga 1−x N with higher indium composition, which is vetoed since a thorough TEM examination has been carried out and neither NW nor quantum dots with high indium concentration can be found. Therefore, it is more likely to be true to associate the relatively broad P3 peak with the structural defects such as basal stacking fault in the In x Ga 1−x N core [14,15,30,31,34], which has been observed in the In x Ga 1−x N core as shown in Figure 6g.…”

“…Low-temperature (LT) PL was employed to characterize the NWs as shown by Figure 7. The sample showed a weak PL shoulder (P1) between 355–362 nm, which could correspond to the neutral donor bound A exciton (D0, XA) recombination (358 nm/3.472 eV) and free A exciton (XA) recombination (357.5 nm/3.477 eV) of the thin GaN shells in the NWs [14,15,30,31]. The second peak P2 is located at 373 nm, which can be attributed to the XA peak from In x Ga 1−x N core.…”

“…Another advantage of In x Ga 1−x N NWs is that they can accommodate lateral lattice mismatch with the substrate and, therefore, suppress the formation of threading dislocations. Other than conventional substrates such as sapphire, SiC, and Si, In x Ga 1−x N NWs have been successfully grown on Ti [11,12], Mo [13], Ta [14], Hf [15], Ni [16], copper [17], stainless steel [18], carbon paper [4,5], etc. [19].…”

Unleashing the potential of molecular beam epitaxy grown AlGaN-based ultraviolet-spectrum nanowires devices

“…can provide the preferred orientation of c-plane growth along the surface normal on any substrates. 71,72 Moreover, the thin film deposited substrates emerge as a less expensive approach, especially for the eventual fabrication of NWs-LEDs ( Table 2).…”

Controlled growth of aligned GaN nanostructures: from nanowires and needles to micro-rods on a single substrate

“…2 achieved nanowire arrays via VLS at 780 C. Tian et al 36 prepared micro-pyramids via SAG at a high temperature about 1080 C. Bae et al 37 investigated the morphologies of micro-pyramids, and they found that micropyramids with smooth sidewalls can only be grown at the temperature higher than 900 C. Rozhavskaya et al 3 reported the growth of micro-rod arrays under 1040 C. Thus, growth temperature of these micro-structures prepared via SAG (950-1175 C) [7][8][9][16][17][18]22,23 is much higher than that of nanowires prepared via VLS (760-850 C). 1,2,12,13,[24][25][26][27]29 Thus, it is still a challenge to simultaneous growth of all these nanostructures (including nanowires and micro-rods) under a favorable condition.…”