Invited Paper GR+EM+MS+NS+SP-FrM1
Epitaxial Graphene Electronics

Friday, November 1, 2013, 8:20 am, Room 101 A

Graphene demonstrates exceptional properties such as high charge carrier mobility and high saturation velocity. Such attributes make graphene a promising candidate for radio frequency (rf) applications. However, one of the key limitations to the realization of graphene’s full potential comes from its interaction with dielectric overlayers and metal contacts, which act to limit the excellent charge transport properties of graphene. We have directly demonstrated the importance of buffer elimination at the graphene/SiC(0001) interface where enhanced carrier mobilities of >3000 cm²/Vs across large scale wafers is possible. Additionally, we have developed a robust method for forming high quality ohmic contacts to graphene, which improves the contact resistance by >1000X compared to untreated metal/graphene interfaces. We have also developed methods for ultra-thin gate oxides, and will discuss integration and the importance on improved interfaces between the graphene and dielectric. Each of these developments have provided a means to achieve graphene transistors with current saturation values >1.5 A/mm, transconductance > 400mS, impressive extrinsic current gain response of epitaxial graphene transistors (>30 GHz), and intrinsic current gain nearing 150 GHz. Additionally, we analyze the third order intermodulation product, gain compression and high frequency noise performance of graphene transistors for low noise amplifier applications and benchmark the graphene transistors with other RF device technologies. The graphene amplifier (un-matched) exhibits an output third order intercept (OIP3) of 19dBm and input 1dB gain compression (P_in,1dB) of 5.6dBm. Finally, the performance of a graphene mixer will be discussed and evidence is provided that matched graphene mixers can outperform current state-of-the-art technologies.