Self-Integrated Hybrid Ultraviolet Photodetectors Based on the Vertically Aligned InGaN Nanorod Array Assembly on Graphene

Abstract

Integration of one-dimensional (1D) semiconductors with two-dimensional (2D) materials into hybrid systems is identified as promising applications for new optoelectronic and photodetection devices. Herein, a selfintegrated hybrid ultraviolet (UV) photodetector based on InGaN nanorod arrays (NRAs) sandwiched between transparent top and back graphene contacts forming a Schottky junction has been demonstrated for the first time. The controlled van der Waals epitaxy of the vertically aligned InGaN NRA assembly on graphene-on-Si substrates is achieved by plasma-assisted molecular beam epitaxy. Moreover, the self-assembly formation mechanisms of InGaN NRAs on graphene are clarified by theoretical calculations with first-principles calculations based on density functional theory. The peculiar 1D/2D heterostructure hybrid system-based integrated UV photodetector simultaneously exhibits ultrafast response time (∼50 μs) and superhigh photosensitivity (∼10 5 A/W). It is highly believed that the concept proposed in this work has a great potential and can be widely applied for the next-generation integrated 1D/2D nano-based optoelectronic and photodetection devices.

Large‐Size Ultrathin α‐Ga2S3 Nanosheets toward High‐Performance Photodetection

“…Furthermore, the corresponding photoresponsivity ( R λ ) and photodetectivity ( D* ) are generally two important factors to evaluate the photodetection performance of a photodetector device. The R λ can be obtained by the Equation (1) [ 44 ] where I ph and I dark are the measured photocurrent under illumination and the dark current, respectively; P is the incident light power intensity; and S is the effective irradiated area (2500 µm 2 ) of photodetector. Moreover, the D* can be calculated by the following Equation (2) [ 33 ] where e is the electron charge; and A is the active area between channels of photodetector.…”

Highly Efficient InGaN Nanorods Photoelectrode by Constructing Z‐scheme Charge Transfer System for Unbiased Water Splitting

“…Moreover, suitable band edge position for water redox reaction, long charge diffuse distance, high surface‐to‐volume ratio and outstanding theoretical solar‐to‐hydrogen (STH) efficiency (≈27%) make InGaN nanorods highly beneficial for PEC overall water splitting. [ 10–12 ] However, the fatal drawbacks such as rapid bulk and surface charge recombination and sluggish oxidation reaction kinetic of InGaN nanorods result in an additional bias required to promote photoextracted charge transfer. [ 13,14 ] Nowadays, constructing semiconductors heterostructure to modulate the energy band of the heterojunction has been considered as one of the most effective methods to promote bulk and surface charge separation.…”

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.…”