Insulating properties of tantalum pentoxide capacitor films obtained by annealing in dry ozone

Autor:	B. K. Moon, J. Aoyama, C. Isobe
Rok vydání:	1999
Předmět:	chemistry.chemical_compound Materials science chemistry Annealing (metallurgy) Electrical resistivity and conductivity Tantalum pentoxide General Physics and Astronomy Grain boundary Crystallite Dielectric Composite material Current density Amorphous solid
Zdroj:	Journal of Applied Physics. 85:1731-1738
ISSN:	1089-7550 0021-8979
Popis:	Highly insulating tantalum pentoxide (Ta2O5) capacitor films were obtained by dry O3 annealing at low temperatures ranging from 350 to 500 °C. Typical leakage current density and resistivity of a 10-nm-thick Ta2O5 film measured at 2 MV/cm were 2.5×10−8 A/cm2 and 4.8×1013 Ω cm, respectively, obtained by dry O3 annealing at 450 °C, while leakage current density of the as-deposited film was about 10−1 A/cm2. It was confirmed that the mechanism which improves the insulating properties after dry O3 annealing involves the reduction of the leakage current due to the reduction of the concentration of such impurities as hydrogen and carbon, and the reduction of oxygen vacancies in Ta2O5 films. In addition, amorphous Ta2O5 films annealed in dry O3 show much better insulating properties than polycrystalline films. This can be attributed to the suppression of leakage current at the grain boundaries. Regarding dielectric properties, Ta2O5 films have an average dielectric constant of 28, and the typical SiO2 equivalent...
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::919945f4a8ea056ebb6ed9306e89cd3a https://doi.org/10.1063/1.369339 Zobrazit plný text záznamu