Structural characterization of CVD diamond films using Raman and ESR spectroscopy methods K. Fabisiak a,b, * , A. Banaszak a , M. Kaczmarski c , M. Kozanecki d a Department of Physics, University of Bydgoszcz, Pl. Weyssenhoffa 11, 85-072 Bydgoszcz, Poland b Department of Biophysics, Medical University of Bydgoszcz, Jagiellon ´ ska 13, 85-067 Bydgoszcz, Poland c Institute of Physics, A. Mickiewicz University, Umultowska 85, 61-614 Poznan ´ , Poland d Faculty of Chemistry, Technical University of Lo ´dz ´, _ Zeromskiego 116, 90-924 Lo ´dz ´, Poland Received 28 September 2004; accepted 3 November 2004 Available online 20 June 2005 Abstract Defects in diamond thin films synthesized by the Hot Filament Chemical Vapor Deposition (HF CVD) method were investigated by Electron Spin Resonance (ESR) and Raman spectroscopy. A series of diamond films of different quality have been synthesized from a mixture of hydrogen and acetylene at different total gas pressure in the range of 20–120 mbar. It was observed that the film morphology changed with increasing deposition pressures from the so-called ‘‘ball-like’’ structure via (1 1 1) and (1 0 0) type texture to the morphology having a mixed character. A comparative study on the ESR and Raman spectra of these films is performed. Ó 2005 Elsevier B.V. All rights reserved. PACS: 81.05.Zx Keywords: Diamond film; Hot Filament CVD; ESR; SEM; Raman spectroscopy 1. Introduction The continuous polycrystalline diamond films are now synthesized routinely from gas phase by using a variety of CVD methods including Hot Filament CVD (HF CVD), Microwave Plasma CVD (MP CVD), and flame methods [1]. The unique physical properties of diamond predesti- nate it for broad application in mechanics, optics and microelectronics. Some physical properties of thin CVD diamond films such as extreme hardness and chemical inertness are similar to that of bulk diamond [2]. The other properties such as for example thermal conductivity, optical trans- parency and electrical conductivity do not achieve the values typical for diamond crystals [3]. In spite of this the current potential applications of diamond films include tool coatings, X-ray and IR optics, abrasives and semiconducting devices. In general the physical properties of CVD diamond films are strongly dependent on the CVD process parameters, the most important are total working gas pressure and composition, flow rate and substrate temperature. The optimization of control parameters is very com- plex and strongly depends on the methods of growth. According to Anthony [4] in the HF CVD method one can count 18 important control parameters and many of them are not independent. The empirical optimiza- tion of all these parameters would require millions of experiments and therefore the understanding of the fun- damental chemistry and physics of the CVD process is still far from complete. 0925-3467/$ - see front matter Ó 2005 Elsevier B.V. All rights reserved. doi:10.1016/j.optmat.2004.11.057 * Corresponding author. Address: Department of Physics, Univer- sity of Bydgoszcz, Pl. Weyssenhoffa 11, 85-072 Bydgoszcz, Poland. E-mail address: kfab@ab-byd.edu.pl (K. Fabisiak). www.elsevier.com/locate/optmat Optical Materials 28 (2006) 106–110