Structural investigation of diamond nanoplatelets grown by microwave plasma-enhanced chemical vapor deposition
- PDF / 1,932,455 Bytes
- 9 Pages / 612 x 792 pts (letter) Page_size
- 68 Downloads / 216 Views
We report a unique morphology of diamond nanoplatelets synthesized by microwave plasma chemical vapor deposition on Ni coated polycrystalline diamond substrates. The diamond nanoplatelets were as thin as approximately 30 nm. Electron microscopy showed that the diamond nanoplatelets appear in a shape consisting of trapezoid and parallelogram tabular crystallites. Furthermore, the diamond nanoplatelets were single crystalline, as shown by electron diffraction. The edges of nanoplatelets were along the 〈110〉 direction with both the top and bottom tabular surfaces parallel to the {111} plane. Transmission electron microscopy revealed that the twinned planes are parallel to the platelet and side-face structure in ridge shape is bounded by {100} and {111} planes. Lateral growth of diamond nanoplatelet is believed to result from twin and ridge face structure. An oriented thin graphite layer was observed on some diamond nanoplatelets.
I. INTRODUCTION
Diamond is an allotrope of carbon and has many outstanding properties, such as the highest hardness, excellent thermal conductivity, biological compatibility, chemical stability, and wide band gap, etc.1 Thus, diamond nanostructure is believed to be vitally significant for the development of nanotechnology in practical applications such as material for severe environments and biological engineering. In comparison with other biological modified materials, diamond exhibits excellent stability, sensitivity, and selectivity, all of which are necessary factors for biosensor platforms.2 Recently, it has been predicted that diamond nanorods may have unusual mechanical properties.3 Furthermore, diamond nanostructure is expected to play an important role for nanoelectromechanical system applications due to its high elastic modulus and strength-to-weight ratio. Because of the high surface energy of diamond, investigation on the stability of nanoscale diamond is also attracting more attention. Theoretical prediction of stability of diamond nanostructure has been addressed.3,4 Recently, several groups have attempted to fabricate diamond nanofibers from a diamond substrate by plasma etching5,6 and by growth on anodic aluminum oxide templates. 7 Other nanostructured diamonds have been
a)
Address all correspondence to this author. e-mail: [email protected] DOI: 10.1557/JMR.2005.0092 J. Mater. Res., Vol. 20, No. 3, Mar 2005
http://journals.cambridge.org
Downloaded: 22 Mar 2015
formed in nanoclusters by ion implantation8 and in nanocrystalline films by chemical vapor deposition (CVD).9 The excellent elastic, mechanical, and thermal properties of nanocrystalline diamond films have already been demonstrated.10 Herein, we present a unique nanostructure of diamond in platelet configuration. Although the platelet morphology of diamond had been reported by Angus et al.,11 it showed that formation of the diamond platelet with low aspect ratio was accompanied with diamond crystallites with three-dimension faceting. Also, the linear dimension of diamond platelets was on a micrometer sc
Data Loading...
