Investigation of the DLC and novel DLC-polymer hybrid coatings using FIB and SEM techniques
|Emilia Choińska 1, Piotr Wieciński 1, Łukasz Ciupiński 1, Wojciech Swieszkowski 1, Veli M. Tiainen 2, Krzysztof J. Kurzydlowski 1|
1. Warsaw University of Technology, Faculty of Materials Science and Engineering (InMat), Wołoska 141, Warszawa 02-507, Poland
|The aim of the present study was to characterize the cross-section of the diamond-like carbon (DLC) and novel DLC-polymer hybrid (DLC-p-h) nanocomposite coatings for medical application. These investigations were done to measure the coatings thickness, analyse the distributions of the DLC and polymer in the coatings and observe the interface between substrate and coatings.
The DLC and DLC- polymer hybrid coatings were deposited on the stainless steel (ANSI 316L) substrate using filtered pulsed arc discharge (FPAD) method. Two different DLC-polymer hybrid coatings have been studied – DLC-polytetrafluoroethylene-h (DLC-PTFE-h) and DLC-polydimethylosiloxane-h (DLC-PDMS-h). The cross-section of the coatings for the SEM and STEM observation have been prepared using the focused ion beam (FIB) Hitachi FB2100 by milling i.e removal bulk material. Because the coatings are made of the polymer, the low energy of the ion beam was used to prepare cross-sections views. The observations of the prepared samples were performed using the HR scanning electron microscope Hitachi S-5500. 3 different modes, such as secondary electrons (SE), backscattered electrons (BSE) and scanning transmission electrons STEM were used to investigate the cross-sections.
The results of microscopic investigations show that the distribution of the constituents in the hybrid coatings depends on the used polymer. In the cross-section of the DLC-PTFE-h coating two separate layers were observed: deeper one - DLC and PTFE at the surface, while DLC-PDMS-h coating was composed of alternating thin sublayers of presumable different phase volume fractions of polymer and DLC, forming a multilayer coating. The STEM observation of the DLC coating indicate amorphous character of this material, what was confirmed by X-Ray diffraction (XRD) results.
Presentation: Poster at E-MRS Fall Meeting 2009, Symposium F, by Emilia Choińska
See On-line Journal of E-MRS Fall Meeting 2009
Submitted: 2009-05-24 21:44 Revised: 2009-06-30 20:00