Layer-transferred MoS2/GaN PN diodes.

Electrical and optical characterization of two-dimensional/three-dimensional (2D/3D) p-molybdenum disulfide/n-gallium nitride (p-MoS₂/n-GaN) heterojunction diodes are reported. Devices were fabricated on high-quality, large-area p-MoS₂ grown by chemical vapor deposition on sapphire substrates. The processed devices were transferred onto GaN/sapphire substrates, and the transferred films were characterized by X-ray diffraction (XRD) and atomic force microscopy (AFM). On-axis XRD spectra and surface topology obtained from AFM scans were consistent with previously grown high-quality, continuous MoS₂ films. Current-voltage measurements of these diodes exhibited excellent rectification, and capacitance-voltage measurements were used to extract a conduction band offset of 0.23 eV for the transferred MoS₂/GaN heterojunction. This conduction band offset was confirmed by internal photoemission measurements. The energy band lineup of the MoS₂/GaN heterojunction is proposed here. This work demonstrates the potential of 2D/3D heterojunctions for novel device applications. [ABSTRACT FROM AUTHOR]