Investigation of Al2O3 layers obtained by DC planar-magnetron sputtering

Abstract

A planar‐magnetron system is used for dc reactive sputtering of Al in O2 + Ar atmosphere. It is shown that the electrophysical properties of so produced alumina (Al2O3) layers depend on the gas ratio mainly. By studying the index of refraction, the dielectric constant, the resistivity, the breakdown field, and the C–V characteristics it is found that the most stoichiometric layers are obtained at a partial pressure ratio, Po2/ArP, in the range of 0.45 to 0.65. The MAS structures show good interface properties only after annealing in N2 at 1000°C and in H2 at 450°C.