The effects of boron dopant on the thermal stability, semiconductor characteristic and wear resistance of diamond films
At a Glance
Section titled “At a Glance”| Metadata | Details |
|---|---|
| Publication Date | 2016-12-22 |
| Journal | Materials Research Innovations |
| Authors | Sea‐Fue Wang, Yung‐Fu Hsu, Feng-Chi Ku, Zu-You Liu |
| Institutions | National Taipei University of Technology |
| Citations | 5 |
Abstract
Section titled “Abstract”In this study, the thermal stability, semiconductor characteristics and wear resistance of boron-doped diamond films deposited using the hot-filament chemical vapour deposition process are characterised and discussed. The crystal quality of the as-grown diamond films becomes more disordered as the CH4 concentration increases to 4% during deposition and the evaporation temperature of the boron source reaches 850 °C. The carrier concentration is not proportional to the boron content in the diamond films because part of the boron atoms present as clusters, which do not contribute to the hole carriers. The resistivity of the diamond film is inversely proportional to the magnitude of the carrier concentration, falling in the range of 1.38 × 10−1-2.26 × 10−3 Ω⋅cm. The onset oxidation temperature of the diamond films, correlating to the crystal quality of the diamond films and ranging from 714 to 967 °C, indicates that the incorporation of boron atoms improves the thermal stability of diamond films in air by as much as 250 °C. The wear rate of the diamond films varies from 2.05 × 10−6 to 17.84 × 10−6 mm3/Nm. An increase in boron incorporation and a rise in the p2 carbon content degrade the wear resistance of the diamond films. Of all the samples prepared, the diamond film deposited at 1% CH4 and associated with a boron source heated at 750 °C is characterised by a nearly pure sp3 bonding of the diamond and demonstrates an electrical resistivity of 1.31 × 10−2 Ω⋅cm, an oxidation temperature of 956 °C and a wear rate of 3.39 × 10−6 mm3/Nm. The diamond film, possessing an improved electrical resistivity and a high oxidation temperature combined with an acceptable wear rate, displays a great potential in the production of wear-resistant coatings, MEMS devices, AFM probes and biomedical sensors.