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The mechanical release of III‐nitride devices using h‐BN is a promising approach for heterogeneous integration. Upscaling this technology for industrial level requires solutions that allow a simple pick‐and‐place technique of selected devices for integration while preserving device performance. An advance that satisfies both of these requirements is demonstrated in this work. It is based on a lateral control of the h‐BN quality, using patterned sapphire with a SiO2 mask, to achieve localized van der Waals epitaxy of high‐quality GaN based device structures. After process fabrication, the devices can be individually picked and placed on a foreign substrate without the need for a dicing step. In addition, this approach could reduce delamination of h‐BN on large diameter substrates because each h‐BN region is smaller, with independent device structures. Discrete InGaN LEDs on h‐BN are grown and fabricated on 2 in. patterned sapphire using a SiO2 mask. A set of devices are selectively released and transferred to flexible aluminum tape. The transferred LEDs exhibit blue light emission around 435 nm. The approach presented here is scalable on any wafer size, can be applied to other types of nitride‐based devices, and can be compatible with commercial pick‐and‐place handlers for mass production. [ABSTRACT FROM AUTHOR]

Highlights from the article: Keywords: 2D boron nitride; core/shell nanostructures; flexible electronics; nanorods; semiconductors; van der Waals epitaxy In article number 1900207, Suresh Sundaram, Abdallah Ougazzaden, and co-workers demonstrate self-organized GaN nanorods formation on layered h-BN templates by van der Waals epitaxial growth. Nanorods, semiconductors, flexible electronics, core/shell nanostructures, van der Waals epitaxy, 2D boron nitride.

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. [ABSTRACT FROM AUTHOR]