Atomic Layer Deposition of TiO[sub 2] Films on Ru Buffered TiN Electrode for Capacitor Applications

This study examined the effect of a Ru buffer layer growth on a TiN electrode on the structural and electrical properties of a dielectric film grown by atomic layer deposition. The growth of a film directly on TiN resulted in the formation of a mixture of anatase and rutile with a dielectric constant of only 42. However, interposing a thin Ru layer altered the crystal structure of from a mixed phase to almost pure rutile, which was accompanied by an abrupt increase in the dielectric constant to . This is a much better result compared with the film deposited on a bulk Ru film, which showed a dielectric constant of . This improvement was attributed to a change in the preferred growth direction of a film on the Ru/TiN layer compared with that on a thicker Ru film.