Effect of substrate pretreatment on the field emission property of nano-amorphous carbon film

In this paper, nano-amorphous carbon films were synthesized on Si substrates by microwave plasma enhances chemical vapor deposition (MPCVD). In order to improve its field emission properties, prior to the deposition of thin films, substrates were first mechanically polished, especially investigated the influence of polishing process of substrates on field emission of the nano-amorphous carbon films were especially investigated. Silicon substrate was used as substrate for the synthesis of the nano-amorphous carbon films; with its area of 1 cm . The source gas for growing films was a mixture of H₂ and CH₄, The typical gas flow rates of H2 and CH4 were 100 seem and 10 seem, respectively, with total pressure of 5.0x10³Pa. The substrate temperature was maintained at 700°C. The deposition time was kept for 3 hour. Two various samples of a and b were prepared, sample a of a un-pretreated silicon plate, and the substrate of sample with mechanically polished by SiC polishing powders, with the diameter of 20μm respectively.