Stable electron field emission from carbon nanotubes emitter transferred on graphene films

• Monolayer Graphene film was grown by chemical vapor deposition (CVD) and transferred on Si substrate.
• Carbon naotubes were synthesized by microwave plasma assisted CVD (MPCVD) and transferred on graphene buffer layer by wetting transfer method.
• Stable filed emission was observed and the reasons were illustrated by introducing the contact resistance and joule heating.

Carbon nanotubes (CNTs) arrays grown by microwave plasma enhanced chemical vapor deposition (MPCVD) method was transferred onto the substrate covered with graphene layer obtained by thermal chemical vapor deposition (CVD) technology. The graphene buffer layer provides good electrical and thermal contact to the CNTs. The field emission characteristics of this hybrid structure were investigated in this study. Compared with the CNTs arrays directly grown on the silicon substrate, the hybrid emitter shows better field emission performance, such as high emission current and long-term emission stability. The presence of this graphene layer was shown to improve the field emission behavior of CNTs. This work provides an effective way to realize stable field emission from CNTs emitter and similar hybrid structures.