A highly sensitive, large area, and self-powered UV photodetector based on coalesced gallium nitride nanorods/graphene/silicon (111) heterostructure

Abstract

In this paper, we demonstrate an ultraviolet photodetector (UV-PD) that uses coalesced gallium nitride (GaN) nanorods (NRs) on a graphene/Si (111) substrate grown by plasma-assisted molecular beam epitaxy. We report a highly sensitive, self-powered, and hybrid GaN NR/graphene/Si (111) PD with a relatively large 100 mm 2 active area, a high responsivity of 17.4 A/W, a high specific detectivity of 1.23 Â 10 13 Jones, and fast response speeds of 13.2/13.7 ls (20 kHz) under a UV light of 355 nm at zero bias voltage. The results show that the thin graphene acts as a perfect interface for GaN NRs, encouraging growth with minimum defects on the Si substrate. Our results suggest that the GaN NR/graphene/Si (111) heterojunction has a range of interesting properties that make it well-suited for a variety of photodetection applications.

Self-powered proton detectors based on GaN core–shell p–n microwires

“…[7][8][9][10][11][12][13] The range of radiation to which GaN is sensitive is extensive 14 and recently GaN has been used to develop self-powered UV and X-ray detectors. [15][16][17][18] Development of growth techniques for GaN also led to fabrication of high quality 1D structures, such as nano-and microwires. 19,20 This mitigates the issue of poor quality GaN films caused by lattice mismatch with the typical growth substrates to a great extent as in the case of nano-and microwires the dislocations are bent to the sidewall surface very close to the bottom, making them essentially dislocation free.…”

In(Ga)N Nanostructures and Devices Grown by Molecular Beam Epitaxy and Metal-Assisted Photochemical Etching

“…The growth parameters can be accurately controlled via in situ monitoring capability. Although the growth rate in MBE is low, it has proven very successful in the growth of optoelectronic device structures [ 99 , 100 ].…”

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

“…The epitaxy caused by a 2-D material, termed van der Waals epitaxy (vdWE), reduces the dislocation density of the grown material, which strongly affects the device properties, and also allows exfoliation of the grown material from the substrate owing to the weak chemical bond. [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.…”