TY - JOUR
T1 - Ambipolar behavior in epitaxial graphene-based field-effect transistors on Si substrate
AU - Olac-Vaw, Roman
AU - Kang, Hyun Chul
AU - Karasawa, Hiromi
AU - Miyamoto, Yu
AU - Handa, Hiroyuki
AU - Fukidome, Hirokazu
AU - Suemitsu, Tetsuya
AU - Suemitsu, Maki
AU - Otsuji, Taiichi
PY - 2010/6/1
Y1 - 2010/6/1
N2 - In this research, ambipolar behavior, which is one of graphene's unique characteristics, is studied for the epitaxial graphene formed on 3C-SiC grown on a Si substrate. The graphene channel is believed to be unintentionally p-type-doped at Dirac-point voltages of approximately +0.11 to +0.12 V. However, as drain voltage negatively increases, Dirac point voltage shifts. The drain current in the p-channel mode of operation saturates at a lower level than that in the n-channel mode of operation. These behaviors are caused by asymmetric carrier transport throughout channelsubstrate heterojunctions (i.e., graphene, thin n-type SiC layer, and p-type Si substrate) and source/drain Schottky metal contacts. The interface between the p-type Si substrate and n-type SiC has a significant effect on transport in graphene channels. The results may be helpful for understanding transport in the device and for suppressing ambipolar operation, leading to a unipolar FET operation.
AB - In this research, ambipolar behavior, which is one of graphene's unique characteristics, is studied for the epitaxial graphene formed on 3C-SiC grown on a Si substrate. The graphene channel is believed to be unintentionally p-type-doped at Dirac-point voltages of approximately +0.11 to +0.12 V. However, as drain voltage negatively increases, Dirac point voltage shifts. The drain current in the p-channel mode of operation saturates at a lower level than that in the n-channel mode of operation. These behaviors are caused by asymmetric carrier transport throughout channelsubstrate heterojunctions (i.e., graphene, thin n-type SiC layer, and p-type Si substrate) and source/drain Schottky metal contacts. The interface between the p-type Si substrate and n-type SiC has a significant effect on transport in graphene channels. The results may be helpful for understanding transport in the device and for suppressing ambipolar operation, leading to a unipolar FET operation.
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U2 - 10.1143/JJAP.49.06GG01
DO - 10.1143/JJAP.49.06GG01
M3 - Article
AN - SCOPUS:77955312161
VL - 49
SP - 06GG011-06GG015
JO - Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes
JF - Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes
SN - 0021-4922
IS - 6 PART 2
ER -