Edge-shaped diamond field emission arrays

The fabrication and field emission behavior of micro-patterned polycrystalline edge-shaped diamond field emission arrays is reported. The edge-shaped diamond field emission arrays were fabricated on a silicon substrate utilizing conventional silicon patterning and etching techniques, and CVD diamond deposition via a mold transferring technique. The mold was filled with diamond using a PECVD process. The silicon was back etched to expose the diamond edges. Edge sharpening was achieved by introducing a silicon oxidation step in the mold fabrication process before the diamond deposition step. The oxide grown was ∼3μm thick. This oxidation process not only sharpened the edge but also served as a gate dielectric for the triode device. Each edge was 125μm in length and 2μm in width. The deposited diamond film was characterized using Raman spectroscopy. The fabricated diamond edge emitter arrays were tested in vacuum (10^-6 Torr). A self-aligned gated edge emitter triode from a silicon-on-insulator (SOI) substrate was also fabricated.