Investigation of emission properties of vacuum diodes with nanodiamond-graphite emitters

Abstract

The aim of the work was to study the effect of various microelectronic structural and technological implementations to improve the field emission properties of the nano-carbon emitters. The field emission properties of vacuum diodes with nanodiamond-graphite emitters of different geometric shapes was researched. The nanodiamond-graphite layers deposition were carried out from ethanol vapor at low pressure using microwave plasma. Three series of experiments were studied. Researching of emission currents with flat cathodes on silicon wafer coated by nanodiamond-graphite layer were done in first series of experiments. In the second series of experiments, the electrical parameters of integrated field emission diodes with flat nanodiamond-graphite emitters was studied. In the third series of experiments, the electrical parameters of field emission with flat nanodiamond-graphite formed as a micro-sized needles or blades were studied. Vacuum emission studies were done at temperature 300K and pressure 1 × 10-6 Torr. Threshold voltage from10-50V per micron and current density about 0.2 A/cm2 were obtained in the first series of experiments. In the second and third series of experiments, a threshold voltage from 1 to 10V/ μm and current density of 1.75 A/cm2 were displayed. The greatest current density more than 20 A/cm2 was obtained using a blade-type emitter.