scholarly journals Nano-patterning on multilayer MoS2 via block copolymer lithography for highly sensitive and responsive phototransistors

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Heekyeong Park ◽  
Jiyoul Lee ◽  
Gyuchull Han ◽  
AbdulAziz AlMutairi ◽  
Young-Hoon Kim ◽  
...  
Keyword(s):  
Block Copolymer ◽  
Structural Engineering ◽  
Trap States ◽  
Highly Sensitive ◽  
Two Dimensional Materials ◽  
Gap States ◽  
Block Copolymer Lithography ◽  
Fundamental Limitation ◽  
Nano Patterning ◽  
Copolymer Lithography

AbstractIndirect bandgap of multilayer molybdenum disulfide has been recognized as a major hindrance to high responsivity of MoS2 phototransistors. Here, to overcome this fundamental limitation, we propose a structural engineering of MoS2 via nano-patterning using block copolymer lithography. The fabricated nanoporous MoS2, consisting of periodic hexagonal arrays of hexagon nanoholes, includes abundant edges having a zigzag configuration of atomic columns with molybdenum and sulfur atoms. These exposed zigzag edges are responsible for multiple trap states in the bandgap region, as confirmed by photo-excited charge-collection spectroscopy measurements on multilayer nanoporous MoS2 phototransistors, showing that in-gap states only near the valence band can result in a photogating effect. The effect of nano-patterning is therefore to significantly enhance the responsivity of multilayer nanoporous MoS2 phototransistors, exhibiting an ultra-high photoresponsivity of 622.2 A W−1. Our nano-patterning of MoS2 for photosensing application paves a route to structural engineering of two-dimensional materials for highly sensitive and responsive optoelectronic devices.

Block copolymer self-assembly assisted fabrication of laterally organized- and stacked- nanoarrays

2021 ◽  
Author(s):  
Vignesh Suresh ◽  
Ah Bian Chew ◽  
Christina Yuan Ling Tan ◽  
Hui Ru Tan
Keyword(s):  
Block Copolymer ◽  
Self Assembly ◽  
The Self ◽  
Functional Surfaces ◽  
Self Assembled ◽  
Block Copolymer Lithography ◽  
Unique Surface ◽  
Copolymer Lithography

Abstract Block copolymer (BCP) self-assembly processes are often seen as reliable techniques for advanced nanopatterning to achieve functional surfaces and create templates for nanofabrication. By taking advantage of the tunability in pitch, diameter and feature-to-feature separation of the self-assembled BCP features, complex, laterally organized- and stacked- multicomponent nanoarrays comprising of gold and polymer have been fabricated. The approaches not only demonstrate nanopatterning of up to two levels of hierarchy but also investigate how a variation in the feature-to-feature gap at the first hierarchy affects the self-assembly of polymer features at the second. Such BCP self-assembly enabled multicomponent nanoarray configurations are rarely achieved by other nanofabrication approaches and are particularly promising for pushing the boundaries of block copolymer lithography and in creating unique surface architectures and complex morphologies at the nanoscale.

Hierarchical nanopores formed by block copolymer lithography on the surfaces of different materials pre-patterned by nanosphere lithography

Nanoscale ◽  
2018 ◽  
Vol 10 (21) ◽  
pp. 10005-10017 ◽  
Author(s):  
Katharina Brassat ◽  
Daniel Kool ◽  
Julius Bürger ◽  
Jörg K. N. Lindner
Keyword(s):  
Block Copolymer ◽  
Nanosphere Lithography ◽  
Block Copolymer Lithography ◽  
Copolymer Lithography

Block copolymer lithography for the nanopatterning of Au, Pt and TiO2 surfaces is presented; by combining this technique with nanosphere lithography, we create hierarchical nanopores.

Sign in / Sign up

Export Citation Format

Share Document