Fabrication of Nano-sized Carbon Emitters by Selective Dry Etching Method

A novel method to make the sharp emitter tips having low threshold voltage of field emission was achieved using nanodiamond particles on conductive amorphous carbon films. A conductive tetrahedral amorphous (ta) carbon film and nano-sized diamond particles with the size of 50 to 200 nm were sequentially deposited by cathordic arc method using a glass substrate at room temperature. Tip structure with the height of 10 to 40 nm was formed by H2 plasma etching of the diamond particles/ta-C double layer film. The threshold voltage of the field emission from the tip structures formed by the H2 plasma etching was 3 V/μm that was significantly lower than 10.4 V/μm for the as-deposited diamond particles/ta-C double layer carbon film. This selective dry etching method using the nano-diamond particles could fabricate sharp and high density nano-sized diamond emitters on conductive ta-C films without any photo-masks of lithography processes.