The Role of Subsurface Oxygen in the Local Oxidation of Zirconium and Zirconium Nitride Thin Films
This paper discusses the growth kinetics of nanometer scale oxide structures grown by atomic force microscope (AFM) assisted lithography. The addition of nitrogen into the sputtering gas during zirconium deposition results in a crystalline ZrN material with oxygen held in solid solution. The diffusion rate of oxygen is high through the crystalline material, allowing it to participate in local anodization and resulting in tall oxide features at low relative humidity. These nanostructures are, in some cases, an order of magnitude higher than previously seen in other material systems. Higher nitrogen content in the plasma results in a crystalline to amorphous transition in the films, and the height enhancement of the AFM-grown features disappears. We propose that mass transport of subsurface oxygen has an influence on surface oxidation kinetics in this material system.
Thin Solid Films
Farkas, N.; Zhang, G.; Donnelly, K. M.; Evans, Edward; Ramsier, R. D.; and Dagata, J. A., "The Role of Subsurface Oxygen in the Local Oxidation of Zirconium and Zirconium Nitride Thin Films" (2004). Chemical and Biomolecular Engineering Faculty Research. 424.