TY - GEN
T1 - Graphene transistors for ambipolar mixing at microwave frequencies
AU - Madan, H.
AU - Hollander, M. J.
AU - Robinson, J. A.
AU - Datta, S.
PY - 2013/10/21
Y1 - 2013/10/21
N2 - This work presents a detailed study of the graphene RF mixer in the ambipolar configuration, using quasi-free-standing epitaxial graphene on SiC. Record high conversion gain is achieved through use of optimized growth and synthesis techniques, metal contact formation, and dielectric materials integration. Hydrogen intercalation is utilized to isolate the graphene from the underlying SiC substrate and improve transport properties. Low contact resistances at the metal-graphene interface are realized using an oxygen plasma pre-treatment, while dielectric seeding is achieved using a direct deposited layer of HfO2 before ALD film growth. Output characteristics of the graphene transistor are analyzed and the effects on mixer performance are explained. A graphene RF transistor is designed with gate length 750nm, width 20μm, and equivalent oxide thickness ∼2.5nm in order to achieve record high conversion gain of -14 and -16dB at LO power 0dBm at 4.2 and 10GHz, respectively, 100× higher than previously reported ambipolar mixing.
AB - This work presents a detailed study of the graphene RF mixer in the ambipolar configuration, using quasi-free-standing epitaxial graphene on SiC. Record high conversion gain is achieved through use of optimized growth and synthesis techniques, metal contact formation, and dielectric materials integration. Hydrogen intercalation is utilized to isolate the graphene from the underlying SiC substrate and improve transport properties. Low contact resistances at the metal-graphene interface are realized using an oxygen plasma pre-treatment, while dielectric seeding is achieved using a direct deposited layer of HfO2 before ALD film growth. Output characteristics of the graphene transistor are analyzed and the effects on mixer performance are explained. A graphene RF transistor is designed with gate length 750nm, width 20μm, and equivalent oxide thickness ∼2.5nm in order to achieve record high conversion gain of -14 and -16dB at LO power 0dBm at 4.2 and 10GHz, respectively, 100× higher than previously reported ambipolar mixing.
UR - http://www.scopus.com/inward/record.url?scp=84885637221&partnerID=8YFLogxK
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U2 - 10.1149/05301.0091ecst
DO - 10.1149/05301.0091ecst
M3 - Conference contribution
AN - SCOPUS:84885637221
SN - 9781607683742
T3 - ECS Transactions
SP - 91
EP - 100
BT - Graphene, Ge/III-V, and Emerging Materials for Post CMOS Applications 5
T2 - 5th International Symposium on Graphene, Ge/III-V and Emerging Materials For Post-CMOS Applications - 223rd ECS Meeting
Y2 - 12 May 2013 through 17 May 2013
ER -