Endoh Norifumi, Akiyama Shoji, Tashima Keiichiro, Suwa Kento, Kamogawa Takamasa, Kohama Roki, Funakubo Kazutoshi, Konishi Shigeru, Mogi Hiroshi, Kawahara Minoru, Kawai Makoto, Kubota Yoshihiro, Ohkochi Takuo, Kotsugi Masato, Horiba Koji, Kumigashira Hiroshi, Suemitsu Maki, Watanabe Issei, Fukidome Hirokazu
Research Institute of Electrical Communication, Tohoku University, Sendai, Miyagi 980-8577, Japan.
Shin-Etsu Chemical Co., Ltd., Chiyoda-ku, Tokyo 100-0004, Japan.
Nanomaterials (Basel). 2021 Feb 4;11(2):392. doi: 10.3390/nano11020392.
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.
石墨烯在下一代器件方面颇具前景。然而,实现这些器件的主要挑战之一是在器件型晶圆上可扩展地生长高质量的少层石墨烯(FLG);在平衡质量和成本的同时做到这一点很困难。高质量的石墨烯是在昂贵的碳化硅块状晶体上生长的,而在硅衬底上生长的碳化硅薄膜上的石墨烯(GOS)质量较低但成本可承受。我们提出了一种在名为“混合碳化硅”的新型模板上生长高质量FLG的新方法。混合碳化硅是通过将碳化硅块状晶体与成本可承受的器件型晶圆键合,随后剥离碳化硅块状晶体以在晶圆上获得单晶碳化硅薄膜而制成的。这种混合碳化硅上的FLG质量与碳化硅块状晶体上的FLG相当,且远高于GOS上的FLG。正如线性能带色散所预期的那样,混合碳化硅上的FLG表现出与碳化硅块状晶体上相当的高载流子迁移率。使用混合碳化硅上的FLG制作的晶体管显示出在太赫兹频率下工作的潜力。所提出的方法适合在所需衬底上生长高质量的FLG,以实现基于石墨烯的高速器件。