INTEgrating GaN nanowire heterostructures on 2D heteRogeneous plAtforms for photodetectION

III-nitride semiconductors (GaN/AlGaN) are strategic materials for photodetection in a broad spectral range from deep ultraviolet to far infrared.

These domains can be addressed thanks to interband and intersubband transitions respectively, which cover wavelengths inaccessible to standard III-V semiconductors.

Heterogeneous integration of III-N nanowires (NWs) on 2D materials at the same time opens new technological opportunities for advanced optoelectronics and presents fundamental interest to elucidate the physics of van der Waals epitaxy (vdWE).

Available research on epitaxial growth of GaN NWs on 2D graphene has demonstrated its promise; however, the scope for improvement remains limited.

A number of questions with fundamental significance e.g. the influence of the 2D material in NW growth, controlling factors for NW size/size-distribution, and generalized understanding of vdWE with experimental authentication remain open.

INTEGRASION proposes to address these open questions and to achieve a general understanding of vdWE of nitrides on 2D materials for advanced optoelectronic devices.

To reach this goal, GaN/AlGaN NWs will be grown on 2D transition metal dichalcogenides (WS2) and comparative analysis will be performed with growth on graphene.

The fundamentals of growth process will be assessed experimentally and theoretically emphasizing the impact of 2D materials on the NW growth which is pivotal for heterojunction formation.

GaN/AlGaN heterojunctions in multi-quantum well structure will be grown on 2D platforms to demonstrate interband UV photodetection as well as intersubband photodetection in mid- and far-infrared domains.

Besides, heterogeneous integration of GaN NWs on 2D platforms will facilitate the post-growth transfer of III-N NWs to flexible substrates where monolithic integration is not possible.

INTEGRASION will address these three key aspects: (i) heterogenous growth, (ii) interband/intersubband photodetection and (iii) hybrid integration.