Site-Selective Atomic Layer Precision Thinning of MoS2 via Laser-Assisted Anisotropic Chemical Etching

Various exotic optoelectronic properties of two-dimensional (2D) transition metal dichalcogenides (TMDCs) strongly depend on their number of layers, and typically manifest in ultrathin few-layer or monolayer formats. Thus, precise manipulation of thickness and shape is essential to fully access their potential in optoelectronic applications. Here, we demonstrate site-selective atomic layer precision thinning of exfoliated MoS2 flake by laser. The oxidation mediated anisotropic chemical etching initiated from edge defects and progressed by controlled scanning of the laser beam. Thereby, the topmost layer can be preferentially removed in designed patterns without damaging the bottom flake. In addition, we could monitor the deceleration of the thinning by in situ reflectance measurement. The apparent slow down of the thinning rate is attributed to the sharp reduction in the temperature of the flake due to thickness dependent optical properties. Fabrication of monolayer stripes by laser thinning suggests potential applications in nonlinear optical gratings. The proposed thinning method would offer a unique and rather straightforward way to obtain arbitrary shape and thickness of a TMDCs flake for various optoelectronic applications.

Medienart:

E-Artikel

Erscheinungsjahr:

2019

Erschienen:

2019

Enthalten in:

Zur Gesamtaufnahme - volume:11

Enthalten in:

ACS applied materials & interfaces - 11(2019), 42 vom: 23. Okt., Seite 39385-39393

Sprache:

Englisch

Beteiligte Personen:

Rho, Yoonsoo [VerfasserIn]
Pei, Jiayun [VerfasserIn]
Wang, Letian [VerfasserIn]
Su, Zhengliang [VerfasserIn]
Eliceiri, Matthew [VerfasserIn]
Grigoropoulos, Costas P [VerfasserIn]

Links:

Volltext

Themen:

Anisotropic chemical etching
Journal Article
Laser thinning
MoS2
Nonlinear optical grating
Single-layer precision thinning
TMDCs

Anmerkungen:

Date Completed 28.10.2019

Date Revised 28.10.2019

published: Print-Electronic

Citation Status PubMed-not-MEDLINE

doi:

10.1021/acsami.9b14306

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM301613478