Electrical Nanocharacterization of Epitaxial Graphene/Silicon Carbide Schottky Contacts

Filippo Giannazzo; Stefan Hertel; Andreas Albert; Antonino La Magna; Fabrizio Roccaforte; M. Krieger; Heiko B. Weber

doi:10.4028/www.scientific.net/MSF.778-780.1142

Paper Titles

SiC Power Devices Operation from Cryogenic to High Temperature: Investigation of Various 1.2kV SiC Power Devices
p.1122

Silicon Carbide Transistors for IC Design Applications up to 600 °C
p.1126

High Temperature Electrical Characterization of 4H-SiC MESFET Basic Logic Gates
p.1130

Controlling the Carrier Concentration of Epitaxial Graphene by Ultraviolet Illumination
p.1137

Electrical Nanocharacterization of Epitaxial Graphene/Silicon Carbide Schottky Contacts
p.1142

Carrier Mobility as a Function of Temperature in as-Grown and H-Intercalated Epitaxial Graphenes on 4H-SiC
p.1146

Stability and Reactivity of [11-20] Step in Initial Stage of Epitaxial Graphene Growth on SiC(0001)
p.1150

Optimizing the Vacuum Growth of Epitaxial Graphene on 6H-SiC
p.1154

Formation of Graphene onto Atomically Flat 6H-SiC
p.1158

HomeMaterials Science ForumMaterials Science Forum Vols. 778-780Electrical Nanocharacterization of Epitaxial...

Electrical Nanocharacterization of Epitaxial Graphene/Silicon Carbide Schottky Contacts

Abstract:

Epitaxial graphene fabricated by thermal decomposition of the Si-face of silicon carbide (SiC) forms a defined interface to the SiC substrate. As-grown monolayer graphene with buffer layer establishes an ohmic interface even to low-doped (e. g. [N] ≈ 10¹⁵ cm^-3) SiC, and a specific contact resistance as low as ρ_C= 5.9×10^-6 Ωcm² can be achieved on highly n-doped SiC layers. After hydrogen intercalation of monolayer graphene, the so-called quasi-freestanding graphene forms a Schottky contact to n-type SiC with a Schottky barrier height of 1.5 eV as determined from C-V analysis and core level photoelectron spectroscopy (XPS). This value, however, strongly deviates from the respective value of less than 1 eV determined from I-V measurements. It was found from conductive atomic force microscopy (C-AFM) that the Schottky barrier is locally lowered on other crystal facets located at substrate step edges. For very small Schottky contacts, the barrier height extracted from I-V curves approaches the value of 1.5 eV from C-V and XPS.