Anh Hoang1,Viet Dongquoc1,Phan Thi Kim Uyen1,Jeong-A Jo1,Eui-Tae Kim1
Chungnam National University1
Anh Hoang1,Viet Dongquoc1,Phan Thi Kim Uyen1,Jeong-A Jo1,Eui-Tae Kim1
Chungnam National University1
Two-dimensional (2D) layered materials, such as graphene and transition metal dichalcogenides, have been extensively studied beyond their applications of bulk Si and compound semiconductor technologies as potential semiconductor platforms. However, their excellent electrical performance, including the carrier mobility, are significantly degraded by molecular adsorption from the environment. High-k oxide dielectric capping layers, such as Al<sub>2</sub>O<sub>3</sub> and HfO<sub>2</sub>, have been applied to suppress Coulomb scattering by shielding the surface from ambient molecules and phonon dispersion, thereby, significantly enhancing the mobility of 2D field-effect transistors (FETs). However, the oxide films not only more often introduce interface trapping defects at the dielectric/2D interface, but also are brittle, so that they cannot be applicable in flexible devices. In this presentation, we report passivation effects of amorphous high-k fluorocarbon (FC) films on graphene FETs. The organic based FC films were deposited on metal-catalytic Si/SiO<sub>2</sub> substrates by using inductively coupled plasma chemical vapor deposition and were subsequently transferred on graphene FETs. Amorphous FC films with high k values more than 30 significantly improved the mobility of graphene FETs, surpassing the corresponding graphene FETs passivated by atomic- layer-deposited Al<sub>2</sub>O<sub>3</sub> film. We will further discuss passivation effects of FC films, including long-term stability and density functional theory calculations.<br/><b> <br/>Keywords: </b>Amorphous fluorocarbon, gate dielectrics, graphene, field-effect transistors <br/>*Corresponding author:
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