Silicon incorporation in CVD diamond layers

✍ Scribed by Barjon, J. ;Rzepka, E. ;Jomard, F. ;Laroche, J.-M. ;Ballutaud, D. ;Kociniewski, T. ;Chevallier, J.

• Publisher: John Wiley and Sons
• Year: 2005
• Tongue: English
• Weight: 161 KB
• Volume: 202
• Category: Article
• ISSN: 0031-8965
• DOI: 10.1002/pssa.200561920

✦ Synopsis

Abstract

The silicon incorporation in diamond is an important issue as silicon is widely used as a substrate for the growth of polycrystalline thin films. Incorporated silicon impurities are suspected to come from the hydrogen etching of the silicon substrate. To clearly establish this point we introduced a solid source of silicon during the growth of a homoepitaxial diamond layer on a HPHT diamond substrate. A quantitative SIMS analysis revealed concentrations of silicon up to 3 × 10^19^ cm^–3^ in the diamond layer. Then we propose a scenario for the contamination of polycrystalline diamond grown on silicon substrates: after nucleation, the progressive paving of the silicon surface by 3D grains causes a fast decrease of its incorporation. At coalescence, the silicon substrate is completely covered by a 2D diamond film and the silicon concentration in diamond reaches a residual level. The investigated MPCVD and HFCVD diamond layers grown on silicon substrates present comparable features. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)