Title: HFCVD nanostructured diamond films deposited by a combination of seeding suspensions and novel nucleation process
Authors: Debarati Mukherjee; Riccardo Polini; Veronica Valentini; Shlomo Zalka Rotter; Joana Catarina Mendes
Addresses: Instituto de Telecomunicações, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal; Department of Electronics, Telecommunications and Informatics, University of Aveiro, 3810-193, Aveiro, Portugal ' Dipartimento di Scienze e Tecnologie Chimiche, Università di Roma 'Tor Vergata', Via della Ricerca, Scientifica 1, 00133 Rome, Italy ' Istituto di Struttura della Materia ISM (CNR), Unit of Montelibretti, Area della Ricerca di Roma 1, Via Salaria Km 29.300, 00015 Monterotondo St. (Rome), Italy ' Instituto de Telecomunicações, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal ' Instituto de Telecomunicações, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal; Centre for Mechanical Technology and Automation, University of Aveiro, 3810-193, Aveiro, Portugal
Abstract: The ultrasonic seeding of a substrate with diamond suspensions enriches the surface with nanometre-sized seeds that coalesce and form a closed conformal film during early stages of diamond growth. To get insight on seeds early growth and evaluate the seeding efficiency of different suspensions, silicon samples were exposed to diamond growth conditions before seeding; this leaves a thin carbon film on the substrate surface. Following this step samples were seeded with commercial nanodiamond suspensions, exposed again to growth conditions and characterised by SEM. Results showed that seeding suspensions played a role depending on particle size and nature of dispersing medium. Seeding density was larger and more uniform in samples pre-exposed to diamond growth conditions. The carbon film deposited during the pre-treatment improves deagglomeration of nanodiamond seeds via a more effective interaction between substrate surface and seeds. This procedure represents a viable way to grow thin conformal diamond coatings by HFCVD.
Keywords: HFCVD; novel nucleation process; NNP; nanodiamond; seeding.
International Journal of Surface Science and Engineering, 2017 Vol.11 No.3, pp.225 - 240
Received: 08 Jan 2016
Accepted: 30 Jun 2016
Published online: 31 Jul 2017 *