Synthesis of CeB6 thin films by physical vapor deposition and their field emission investigations

High quality CeB6 thin films have been obtained through direct evaporation of raw micron-sized CeB6 powders at a pressure of 70 Pa. The X-ray diffraction (XRD), Raman spectrum, scanning electron microscope (SEM), transmission electron microscopy (TEM), selected-area electron diffraction (SAED) and the field-emission equipment were used to characterize the morphology, structure, composition and FE properties of the samples. The XRD and Raman spectrum analysis results show the as-prepared product is cubic phase CeB6. The TEM, SAED and HRTEM analysis reveal that the samples are mixtures of thin films (polycrystalline) and small crystals (single crystallines aligned preferentially in the [1 1 0] direction). Compared to oxide nanostructures, field-emission measurements show that the CeB6 films have better FE performance with turn-on field and threshold field of 12.93 V/μm and 14.86 V/μm, respectively.