Thermal reactions of sputtered Cu films on the thermally grown silicon dioxide (SiO 2) and spin-on hydrogen silsesquioxane (HSQ) layers are investigated by examining the sheet resistance, surface microstructure, phase formation, and compositional depth profiles of Cu/thermal SiO 2 and Cu/HSQ structures on Si wafers after annealing in vacuum at 400-700°C. The sheet resistance values of both samples decreased after annealing at 400°C. The decrease in sheet resistance occurred in conjunction with growth of Cu grains and annihilation of microcracks of the as-deposited Cu films. Cu 2O was first found in the Cu/HSQ/〈Si〉 samples after annealing at 600°C, After annealing at 700°C, the whole copper layer of Cu/HSQ/〈Si〉 sample reacted with oxygen to form several copper oxides. On the contrary, only a minor part of copper in Cu/thermal SiOn/〈Si〉 structure was transformed to Cu 2O after annealing at 700°C. The reaction and/or diffusion characteristics of the two structures upon vacuum annealing are discussed.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Renewable Energy, Sustainability and the Environment
- Condensed Matter Physics
- Surfaces, Coatings and Films
- Materials Chemistry