Abstract
Polycrystalline diamond films were deposited using a methane/hydrogen gas mixture in a microwave plasma-assisted chemical vapor deposition system. In this research, a conduction mechanism was successfully established for the Al/undoped diamond structure in the temperature range of 30–300°C. It was found that the rectifying properties of the Al/undoped diamond structure at room temperature exhibited more ohmic behavior at high temperatures. It was suggested that the oxidation layer in the metal/diamond interface was degraded, and more currents flowed through the bulk diamond crystallites and the diamond grain boundaries after the high-temperature measuring process. It was suggested that a Schottky contact was also formed in the diamond grain boundaries. The modified equivalent circuit for the Al/undoped diamond structure is an ideal Schottky diode in series with the bulk resistance for the bulk diamond crystallites, which is also parallel to an opposite pole of the ideal Schottky diode in series with the grain boundary resistance for the diamond grain boundaries. Both the space-charge-limited transport mechanism and the field-activated transport mechanism were considered for the Al/undoped diamond structure. It was found that the field-activated transport mechanism, in which the series resistance can be represented by the Frenkel-Poole equation, had a better fit to the experimental data.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
