상세정보
학술지
Very Large Suspended Graphene as an Efficient Electron-transparent Gate Electrode
- 발행일
- 201708
- 출처
- Carbon, v.119, pp.371-377
- ISSN
- 0008-6223
- 출판사
- Elsevier
- 초록
- Although a focused electron beam is required in field emission-based various applications, the electron beam is generally diverged in a conventional triode because the gate has a circular aperture through which the electrons are accelerated to reach the anode. To prevent the beam divergence, a suspended multi-layer graphene (MLG) was fabricated on a very large gate aperture to be used as an electron-transparent gate in a field emission triode. The suspended MLG was observed to have several micro-openings with an average diameter of ~5혻μm formed during a transfer. It was observed that the MLG with micro-openings was likely to act as an efficient transparent gate for electrons even with large number of graphene layers, exhibiting a high transmittance of ~90%. The solid angles of the beams obtained using conventional gate aperture and suspended MLG gate were 0.225 and 0.074 sr, respectively, indicating that the suspended MLG resulted in a focused electron beam. Simulations confirm that the suspended MLG with micro-openings suppresses the beam divergence in a given triode configuration because the MLG results in the flattened electric field profiles between gate and cathode whereas a distorted potential distribution causing beam divergence occurs around the aperture in a conventional triode.
- KSP 제안 키워드
- Average diameter, Beam Divergence, Circular aperture, Electron Beam, Field emission triode, Field profiles, High transmittance, Number of graphene layers, Solid Angle, Suspended Graphene, electric field