High temperature stability in lanthanum and zirconia-based gate dielectrics

Autor:	B. W. Busch, Torgny Gustafsson, Angus I. Kingon, H. Schulte, Jon Paul Maria, Dwi Wicaksana, Eric Garfunkel
Rok vydání:	2001
Předmět:	Materials science Annealing (metallurgy) Alloy Analytical chemistry Oxide General Physics and Astronomy Dielectric Partial pressure engineering.material chemistry.chemical_compound Chemical engineering chemistry Torr engineering Cubic zirconia Thermal stability
Zdroj:	Journal of Applied Physics. 90:3476-3482
ISSN:	1089-7550 0021-8979
Popis:	Gate dielectrics composed primarily of lanthana and zirconia were prepared by reactive evaporation. The stability of the layers during high temperature anneals was investigated. By controlling the oxygen partial pressure during heat treatment, lanthana and zirconia films could be protected against reaction with the underlying Si substrate and against the growth of low-e interface layers. The electrical thickness of the dielectrics could be maintained after a 900 °C exposure. The critical oxygen pressure at 900 °C for low-e interface formation beneath ZrO2 and La2O3 dielectrics was ∼2e−4 Torr. The interfaces that formed beneath the ZrO2 and La2O3 layers are distinctly different. The sub-ZrO2 interface, influenced primarily by phase separation, tends towards pure SiO2, while the sub-La2O3 interface, influenced primarily by silicate formation, tends towards a La–Si–O alloy. For both materials, reducing the oxygen pressure to values below 10−7 Torr resulted in rapid degradation of the metal oxide. This dielec...
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::e68c6f782927ee0717020115cf5a1288 https://doi.org/10.1063/1.1391418 Zobrazit plný text záznamu