Research | ligroup

Research Highlights (selected)

2D vertical FET

Comparison of 2D planar FET and vertical FET based on a MoS2/Gr heterostructure (in preparation).

MoS2 suspended structure

Microscopy and SEM images of suspended structure using monolayer and multilayer MoS2 (in preparation).

MoS2/WSe2 heterobilayer solar cell

A 2D heterobilayer structure for high-efficiency and high-density solar cell applications (in preparation).

Photoresponse of HfSe2 and ZrSe2

Anisotropic LSPR response has been investigated in 2D HfSe2 and ZrSe2 in two extreme conditions: in-plane direction vs out-of-plane direction and monolayer vs multilayer (Semicond. Sci. Technol., 2018).

NDR observed in a 2D heterojunction

Quantum tunneling with the signature of NDR was demonstrated in a 2D heterojunction composited of black phosphorus and MoS2 (ACS Nano, 2017).

MoS2 nanotube/nanoribbon FET

An MoS2 nanotube/nanoribbon FET with reconfigurable electric double layer gating (IEEE Trans. Electron Devices, 2017).

MoS2 p-n junction

A homogeneous MoS2 vertical p-n junction made by chemical doping. The thickness is scaled down 3 nm which is the world's thinnest so far (Nat. Commun., 2015).

MoS2 photodetector

A back-gated MoS2 transistor used as a photodetector. A gate-controlled metal-semiconductor barrier modulation determines the efficiency of charge carrier collection (Sci. Rep., 2014).

Graphene photodetector

A graphene photodetector with enhanced photoresponse due to trap assistance (IEEE IEDM, 2012).

Cu intercalated WS2

Molecular structures of intrinsic WS2 and Cu intercalated WS2 (in preparation).

EDL-gated graphene transistor

An epitaxially grown graphene on SiC gated by electric double layer (EDL) using solid polymer electrolyte (PEO:LiClO4) (J. Phys. Chem. C, 2017).

CVD MoS2 transistor

A CVD-synthesized MoS2 transistor with h-BN decorated metal-semiconductor contact (in preparation).

Research Posters (selected)

Research Videos

Research Focuses

Novel physics and engineering of 2D materials including graphene (Gr), hexagonal boron nitride (h-BN), transition metal dichalcogenides (TMDs), monochalcogenides (MXs), carbon nitride (CN), and their van der Waals hetero-structures and hybrid systems.

Application of high-performance energy-efficient 2D nanoelectronic devices including field-effect transistors, tunnel transistors, cold-source transistors, memories, photosensors, and solar cells, etc.

Research Activities

Material growth, engineering, and device fabrication by micro- and nano-electro-mechanical systems (MEMS/NEMS).

Material and device characterization by various electrical, spectroscopy and microscopy techniques.

Theory and modeling of material properties and device performance.