A route to diamond wafers by epitaxial deposition on silicon via iridium/yttria-stabilized zirconia buffer layers

Abstract

A multilayer structure is presented which allows the deposition of high-quality heteroepitaxial diamond films on silicon. After pulsed-laser deposition of a thin yttria-stabilized zirconia (YSZ) layer on silicon, iridium was deposited by e-beam evaporation. Subsequently, diamond nucleation and growth was performed in a chemical vapor deposition setup. The epitaxial orientation relationship measured by x-ray diffraction is diamond(001)[110]∥Ir(001)[110]∥YSZ(001) [110]∥Si(001)[110]. The mosaicity of the diamond films is about an order of magnitude lower than for deposition directly on silicon without buffer layers and nearly reaches the values reported for single-crystal diamond on Ir/SrTiO3. In the effort towards single-crystal diamond wafers, the present solution offers advantages over alternative growth substrates like large-area oxide single crystals due to the low thermal expansion mismatch.