Enhanced transport and transistor performance with oxide seeded high-κ gate dielectrics on wafer-scale epitaxial graphene

Nano Lett. 2011 Sep 14;11(9):3601-7. doi: 10.1021/nl201358y. Epub 2011 Aug 4.

Abstract

We explore the effect of high-κ dielectric seed layer and overlayer on carrier transport in epitaxial graphene. We introduce a novel seeding technique for depositing dielectrics by atomic layer deposition that utilizes direct deposition of high-κ seed layers and can lead to an increase in Hall mobility up to 70% from as-grown. Additionally, high-κ seeded dielectrics are shown to produce superior transistor performance relative to low-κ seeded dielectrics and the presence of heterogeneous seed/overlayer structures is found to be detrimental to transistor performance, reducing effective mobility by 30-40%. The direct deposition of high-purity oxide seed represents the first robust method for the deposition of uniform atomic layer deposited dielectrics on epitaxial graphene that improves carrier transport.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.