Characterization of thin carbon films capable of low-field electron emission

Previous experiments have demonstrated that carbon nanoisland films (or disordered quantum-dot arrays) deposited on silicon wafers may possess the property of low-field electron emission. This paper presents our new work on comparative characterization of emitting and nonemitting thin carbon films. The experimental results acquired by Auger spectroscopy,electron energy loss spectroscopy, Anderson's technique for workfunction measurement, and secondary-emission techniques confirmed that the emitting films are discontinuous and consist of carbon in sp(2)-hybridization state, while their workfunction is relatively high (>4 eV). These experimental data clearly contradict the commonly accepted Fowler-Nordheim theory of field emission and suggest that the observed emission phenomenon has a different nature. A novel model is proposed as a development of the well-known hot-electron emission mechanism supplemented with nanoscale-related features of thermoelectric phenomena. Published by the AVS.