Vacuum microelectronics has been studied for decades to develop unique devices such as rf-generators, high efficiency flat panel displays, x-ray sources and so on. In recent years field emitters based on carbon nanotubes (CNTs) and other nanomaterials have demonstrated high emission current densities making them prime candidates for next generation vacuum microelectronic applications. However their emission efficiency and stability is hindered by non-uniform emission and emitter destruction in high electric field conditions. By utilizing an amplifying structure such as a microchannel plate (MCP) which functions as an electron amplifier the total emission current of the emitters can be enhanced. In addition, MCP can act as a rigid shield for protecting the emitters from destruction. Standard MCP cannot be used for this purpose due to their limited amplification resulting from lower secondary yield of its materials. In this presentation we will discuss our results, on the design and fabrication of a novel ceramic MCP based on high secondary yield materials. 18 time’s higher emission current was achieved from CNT field emitters when the MCP was placed over them. We will also present our results the design of a new CNT multistage field emitter structure which consisted of periodic arrays of SWNT/thin-MWNT on MWNT. Higher field emission current ~32 times and low threshold field ~1.5 times were obtained for these structures in comparison to only MWNT arrays.
Journal: TechConnect Briefs
Volume: 1, Nanotechnology 2008: Materials, Fabrication, Particles, and Characterization – Technical Proceedings of the 2008 NSTI Nanotechnology Conference and Trade Show, Volume 1
Published: June 1, 2008
Pages: 59 - 62
Industry sector: Advanced Materials & Manufacturing
Topics: Carbon Nano Structures & Devices