화학공학소재연구정보센터
학회 한국재료학회
학술대회 2018년 가을 (11/07 ~ 11/09, 여수 디오션리조트)
권호 24권 2호
발표분야 F. 광기능/디스플레이 재료 분과
제목 High Speed and Gate Controllable Graphene Photodetector
초록 Graphene is expected to be suitable for use as an optical device because of its high bandwidth approaches 500 GHz and has a high cutoff frequency of ~60 GHz and mobility of ~ 105 cm 2 / Vs. Despite the excellent performance of graphene, it is difficult to use graphene in optical devices due to the graphene band structure. The photodetector of this study is an FET structure with graphene as the active layer and the metal back electrode as the metal electrode, local top gate, source and drain. Graphene synthesized by the CVD method was transferred to a Si wafer and used as an active layer, and a global back gate was used for Si p-doped in a large amount. The local top gate was defined by electron beam lithography and deposited by Ti / Au sputtering. When a bias is applied to the top gate in order to invert the carrier type of the active layer, a pn junction is formed in which a photocurrent generated at the gate end is formed. In order to eliminate the gaps between the graphene, the method for producing graphene nanoribbons and the preparation of defects in graphene are not yet complete, as they may reduce the carrier mobility of graphene. Therefore, a method to solve the gapless problem of graphene was adopted. This research eliminates the graphene gap and does not lower the high carrier mobility of graphene, so it can be applied to high speed photodetectors such as optical computing and optical communication.

This work was supported by 2E28200 (KIST)
References
[1] Charles M. Marcus et al. Nano Letter, 11, 4134-4137 (2011).
[2] Leonid S. Levitov et al, Nano Letter, 11, 4688-4692 (2011).
[3] Xiaodong Xu et al. Nature Nanotechnology, 7, 114-118 (2012).
[4] Pablo Jarillo-Herrero et al. Science, 334, 648-652 (2011).
저자 인재현1, 이정상2, 주현수2, 주병권1, 이전국2
소속 1고려대, 2한국과학기술(연)
키워드 <P>phototransistor; graphene; 2d material; dual gate structure</P>
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