Electrical characteristics and interface structure of HfAIO/SiON/Si(001) stacks

• Autor(a) principal: Edon, Vincent
• Data de Publicação: 2007
• Outros Autores: Li, Z., Hugon, Marie-Christine, Agius, Bernard, Krug, Cristiano, Baumvol, Israel Jacob Rabin, Durand, Olivier, Eypert, Céline
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UFRGS
• Texto Completo: http://hdl.handle.net/10183/141706
• topic: Propriedades dielétricas; Capacitores; Filmes finos dieletricos

The electrical characteristics of RuO2 /HfAlO/SiON/Si 001 capacitors prepared by thermal nitridation of the Si substrate previously to HfAlO ultrathin film deposition were determined. A dielectric constant of 19 and a gate current density of 67 mA/cm2 for an equivalent oxide thickness of 1.1 nm have been determined, whereas non-nitrided capacitors gave substantially lower dielectric constant and higher gate current density. The structure and integrity of the stacks after thermal annealing were accessed by means of spectroscopic ellipsometry and x-ray reflectometry, indicating that thermal N incorporation into the gate dielectric stacks forms an effective diffusion barrier, leading to a smoother, SiO2-like interface. The HfAlO films grown on nitrided substrates were seen also to have lower porosity, percentage of voids, and density of oxygen vacancies.