Theoretical Investigation of Field Emission of Aligned Carbon Nanotubes Grown by DC HF CVD Process

摘要

We report a theoretical investigation of the field emission from aligned carbon nanotubes (CNTs) grown by the direct current and hot filaments catalytic chemical vapour deposition method referred to the DC HF CCVD process that have previously been studied by other techniques. SEM/TEM images and GISAXS patterns were analyzed to extract structural and morphological parameters required to interpret the field emission. These parameters were needed to simulate the standard Fowler-Nordheim plots which were in agreement with those previously reported in the literature. Analysis of these plots allows one to determine the field enhancement factor β which results with a high content of ammonia (3%) in the gas mixture are remarkable. On the other hand, the surface emission is found to be lower with a high content of ammonia. We saw an improvement in the field emission properties with a high content of ammonia in the gas mixture and low surface emission during our analysis. These CNTs have excellent emission characteristics such as a low threshold field for emission and a high current density, a small effective surface emission and high field enhancement factor. By processing these characteristics, the CNTs produced here are good candidates to be used in CNT field emitter devices application.