Study of Freestanding carbon nanotube array field emission uniformity with field emission microscopy

Field emission microscopy (FEM) has been used in materials science to investigate molecular surface structures and their electronic properties. Since PMMA thin film is electron sensitive, it allows us to visualize and record the FE performance of the CNT arrays. In this article, we demonstrate a PMMA thin film based FEM to analyze the field emission (FE) uniformity of free standing carbon nanotube (CNT) array. The FE dose (product of FE current and time) and spatial distribution of CNT arrays of two different densities are recorded and the deviation of the FE performance of CNT emitters is visualized as different morphology of FEM patterns on the PMMA thin film. This method facilitates the study of FE non-uniformity and emitter degradation mechanism.