Large‐Area van der Waals Epitaxial Growth of Vertical III‐Nitride Nanodevice Structures on Layered Boron Nitride

Abstract

Hexagonal boron nitride (h‐BN) is a promising 2D template that decouples substrate effects from the layer above it by van der Waals epitaxy, because there are only weak forces out of the h‐BN. It also permits convenient mechanical transfer of devices grown on their surface to an appropriate substrate. Here, van der Waals epitaxial growth resulting in the formation of self‐organized GaN nanorods on h‐BN templates is demonstrated. This approach to the growth of III‐N nanostructures avoids transfer processes and scaling issues seen with other 2D materials, since both the 1D (GaN nanorods) and 2D (h‐BN) are grown at the wafer‐scale and in one growth run. Further, this process is used to grow vertical core–shell p‐GaN/InGaN/n‐GaN nano‐PIN device structures on wafer‐scale 2D h‐BN on sapphire and silicon substrates. The high quality of the core–shell nanostructures is confirmed by detailed electron microscopy study, which gives more insight into the nanorod formation mechanism on 2D material. Mechanical transfer of nanostructures on sapphire substrates to copper tape is then demonstrated, with no resulting damage of nanorods. Use of MOVPE grown large‐area h‐BN to realize nanostructures is a significant advancement and can lead to new nanodevice architectures needed for next‐generation optoelectronic devices.

The stability of graphene and boron nitride for III-nitride epitaxy and post-growth exfoliation

“…† As reported in previous studies, the 2-D h-BN layer serving as a platform for III-nitrides vdWE and/or RE could be another option to overcome the stability issue of graphene on a substrate that contains the N atom discussed above. 19,20 For comparison, we also examined the stability of the h-BN lm on AlN using an identical annealing process to that used for graphene on AlN in this work. The AFM images in Fig.…”

“…[1][2][3][4] The advantages of vdWE have been conrmed using various structures, such as gallium nitride (GaN) or aluminium nitride (AlN) growth on graphene/silicon carbide (SiC), 5 graphene/ silicon dioxide (SiO 2 ), [6][7][8][9] graphene/silicon (Si), [10][11][12] graphene/ sapphire (Al 2 O 3 ), [13][14][15][16][17][18] and hexagonal boron nitride (h-BN)/ Al 2 O 3 . 19,20 However, the remaining dislocation density on vdWE is still a hurdle to achieving high-quality semiconductors.…”

Van der Waals heterostructures with one-dimensional atomic crystals

“…2D vdW layered materials have been extensively studied as the substrate for epitaxy growth [101][102][103][104][105][106][107]. Their chemically inert and dangling-bond-free surface also enable 1D atomic crystals to be easily integrated via weak vdW interaction [108][109][110][111][112][113][114][115][116][117][118][119][120].…”

Detecting overlapping semiconductor nanopillars and characterization

“…Therefore, detecting and characterizing such arrays in an automatic fashion is very desirable in order to dramatically reduce the amount of time it takes to analyze large or even small datasets because automatic schemes have the ability to analyze dozens of pictures in the matter of seconds where a human would take Fig. 1: Isometric view of the nanorods [3]. In contrast to literature dealing with structured overlap shapes such as [4], the above figure highlights the random and chaotic nature of the overlaps being characterized in this paper.…”