High-Quality Few-Layer Graphene on Single-Crystalline SiC thin Film Grown on Affordable Wafer for Device Applications.

Norifumi Endoh,Yoshihiro Kubota,Shoji Akiyama,Takamasa Kamogawa,Minoru Kawahara,Maki Suemitsu,Kento Suwa,Shigeru Konishi,Masato Kotsugi,Issei Watanabe,Hirokazu Fukidome,Kazutoshi Funakubo,Makoto Kawai,Hiroshi Mogi,Roki Kohama,Keiichiro Tashima,Hiroshi Kumigashira,Koji Horiba,Takuo Ohkochi

doi:10.3390/nano11020392

Abstract

Graphene is promising for next-generation devices. However, one of the primary challenges in realizing these devices is the scalable growth of high-quality few-layer graphene (FLG) on device-type wafers; it is difficult to do so while balancing both quality and affordability. High-quality graphene is grown on expensive SiC bulk crystals, while graphene on SiC thin films grown on Si substrates (GOS) exhibits low quality but affordable cost. We propose a new method for the growth of high-quality FLG on a new template named “hybrid SiC”. The hybrid SiC is produced by bonding a SiC bulk crystal with an affordable device-type wafer and subsequently peeling off the SiC bulk crystal to obtain a single-crystalline SiC thin film on the wafer. The quality of FLG on this hybrid SiC is comparable to that of FLG on SiC bulk crystals and much higher than of GOS. FLG on the hybrid SiC exhibited high carrier mobilities, comparable to those on SiC bulk crystals, as anticipated from the linear band dispersions. Transistors using FLG on the hybrid SiC showed the potential to operate in terahertz frequencies. The proposed method is suited for growing high-quality FLG on desired substrates with the aim of realizing graphene-based high-speed devices.

Highlights

IntroductionGraphene, which is a two-dimensional honeycomb lattice of carbon atoms, exhibits a linear band dispersion of π-electrons near the Fermi level [1,2,3,4,5]
We examined the quality of the hybrid SiC by using X-ray diffraction (XRD) and X-TEM, and AFM
We established the high-quality growth of few-layer graphene (FLG) on a substrate termed hybrid SiC, which consists of a high-quality SiC thin film uniformly transferred from a SiC single crystal onto a device-type wafer with an affordable cost, compared to the graphene growth method using SiC bulk crystals

Summary

Introduction

Graphene, which is a two-dimensional honeycomb lattice of carbon atoms, exhibits a linear band dispersion of π-electrons near the Fermi level [1,2,3,4,5]. Short-channel effects, which inhibit device integration, are suppressed in graphene, owing to its ultimate thinness [7] These properties make graphene attractive for use in next-generation devices, such as field-effect transistors (FETs) [2,3,8,9] and lasers with frequencies in the terahertz range [10,11], which can provide the missing link between electronic information processing and optical communications [12]

Methods

Results

Conclusion