TY - JOUR

T1 - Atomically Thin Mica Flakes and Their Application as Ultrathin Insulating Substrates for Graphene

AU - Castellanos-Gomez, Andres

AU - Wojtaszek, Magdalena

AU - Tombros, Nikolaos

AU - Agrait, Nicolas

AU - van Wees, Bart J.

AU - Rubio-Bollinger, Gabino

AU - Agraït, Nicolás

PY - 2011/9/5

Y1 - 2011/9/5

N2 - By mechanical exfoliation, it is possible to deposit atomically thin mica flakes down to single-monolayer thickness on SiO(2)/Si wafers. The optical contrast of these mica flakes on top of a SiO(2)/Si substrate depends on their thickness, the illumination wavelength, and the SiO(2) substrate thickness, and can be quantitatively accounted for by a Fresnel-law-based model. The preparation of atomically thin insulating crystalline sheets will enable the fabrication of ultrathin, defect-free insulating substrates, dielectric barriers, or planar electron-tunneling junctions. Additionally, it is shown that few-layer graphene flakes can be deposited on top of a previously transferred mica flake. Our transfer method relies on viscoelastic stamps, as used for soft lithography. A Raman spectroscopy study shows that such an all-dry deposition technique yields cleaner and higher-quality flakes than conventional wet-transfer procedures based on lithographic resists.

AB - By mechanical exfoliation, it is possible to deposit atomically thin mica flakes down to single-monolayer thickness on SiO(2)/Si wafers. The optical contrast of these mica flakes on top of a SiO(2)/Si substrate depends on their thickness, the illumination wavelength, and the SiO(2) substrate thickness, and can be quantitatively accounted for by a Fresnel-law-based model. The preparation of atomically thin insulating crystalline sheets will enable the fabrication of ultrathin, defect-free insulating substrates, dielectric barriers, or planar electron-tunneling junctions. Additionally, it is shown that few-layer graphene flakes can be deposited on top of a previously transferred mica flake. Our transfer method relies on viscoelastic stamps, as used for soft lithography. A Raman spectroscopy study shows that such an all-dry deposition technique yields cleaner and higher-quality flakes than conventional wet-transfer procedures based on lithographic resists.

KW - FEW-LAYER GRAPHENE

KW - SINGLE-LAYER

KW - FILMS

KW - GRAPHITE

KW - CRYSTALS

KW - SILICON

KW - SHEETS

KW - SIO2

U2 - 10.1002/smll.201100733

DO - 10.1002/smll.201100733

M3 - Article

VL - 7

SP - 2491

EP - 2497

JO - Small

JF - Small

SN - 1613-6810

IS - 17

ER -