Fabrication of n-type ZnO nanowire/graphene/p-type silicon hybrid structures and electrical properties of heterojunctions

Abstract

Compared to the p-n junction type device (Device A) with an n-type ZnO nanowire (n-ZnO)/p-type silicon (p-Si) hybrid structure, the newly designed device (Device B) with an n-ZnO/reduced graphene oxide sheet (rGO)/p-Si hybrid structure displays interesting electrical characteristics such as lower turn-on voltage and better current symmetry. The addition of rGO between n-ZnO and the p-Si substrate enables tuning of the p-n junctions into back-to-back Schottky junctions and lowering of the turn-on voltages, implying great potential applications in electronic and optoelectronic devices. The electrical characteristics and operating mechanism of these two devices are fully discussed.

Electrical behaviors of ZnO/graphene/Si and ZnO/graphene/PS composite structures obtained by spraying different volumes of graphene solution

“…Hence, the ZnO/G/Si device has two back-to-back Schottky junctions at the interfaces. Our observations related to the Schottky barrier behavior of the ZnO/G/Si devices are aligned with the results reported by Liang et al [4].…”

“…Although ZnO and graphene have separately shown great potential for various applications (as discussed above), the studies on their hybrid structures have recently started. The hybrid structures of ZnO and graphene having high current and distinct light emission can serve as multi-functional conductors [4].…”

“…ZnO thin films can be grown on different substrates, and the choice of substrate affects its physical, optical, and electrical properties. There is an emerging interest in growing ZnO structures on graphene layers [4]. Graphene, a single layer graphite having closely packed hexagonal lattices, has received a lot of research interest due to its unique structure and fascinating properties [5,6].…”

Hydrothermally Grown In-doped ZnO Nanorods on p-GaN Films for Color-tunable Heterojunction Light-emitting-diodes

“…ZnO, which possesses a wide band-gap (3.37 eV) and a high exciton-binding energy (60 meV), is a promising n-type semiconducting material in optoelectronic devices such as solar cells, laser diodes (LDs), and light emitting diodes (LEDs) 1 2 3 4 . The 1D nanostructures based on this material, especially nanowires (NWs) and nanorods (NRs), have recently attracted considerable attention for practical application in LEDs because they provide effective conduction paths for electrons due to their high crystallinity compared to a thin-film structure 5 6 7 . Vertically-aligned ZnO NWs/NRs can also act as direct waveguides that minimize the side scattering of the light, and thus enhance the light extraction efficiency without use of reflectors and lenses 8 .…”

Effects of GaxZn1−xO nanorods on the photoelectric properties of n-ZnO nanorods/p-GaN heterojunction light-emitting diodes

“…One-dimensional nanostructures such as nanorods (NRs) and nanowires (NWs) have been extensively studied, [1][2][3] since their high crystallinity can provide an effective electron conduction path, 4 and the vertical arrangement of NRs/NWs can also reduce the light of lateral scattering and enhance the light extraction efficiency, 5,6 which makes it better than traditional planar p-n junction light-emitting diodes (LEDs).…”