Analytical Spectroscopic Ellipsometry of Ta2O5 and TiO2 for Use as High-k Gate Dielectrics
Curt A. Richter, Nhan Van Nguyen, G A. Alers, X Guo, Xiaorui Wang, T P. Ma, T Tamagawa
Extended abstract on Analytical Spectroscopic Ellipsometry of Ta2O5 and TiO2 for Use as High-k Gate Dielectrics. Opening paragraph of abstract: There is tremendous interest in high dielectric constant (high-k) films to use as alternates to SiO2 to continue traditional CMOS scaling. Proper methods to interpret ellipsometry, a widely used method for process control, are needed for these new materials. Unlike SiO2, which has well-accepted handbook values for the index of refraction, little is known about the optical properties of high-k materials on Si. We present spectroscopic ellipsometry (SE) studies of TiO2 and Ta2O5, two proposed high-k gate dielectrics. We report an effective protocol to analytically characterize amorphous, high-k dielectric materials developed during studies of Ta2O5. This is then applied to characterize the optical properties of Jet Vapor Deposition (JVD) TiO2/Si3N4 gate dielectrics which have excellent device properties as reported by Guo, et al. We also contrast the effect that increased dielectric constants have on electrical and optical measurements illustrating the complementary nature of these techniques.
Workbook of the 30th IEEE Semiconductor Interface Specialist Conference
, Nguyen, N.
, Alers, G.
, Guo, X.
, Wang, X.
, Ma, T.
and Tamagawa, T.
Analytical Spectroscopic Ellipsometry of Ta<sub>2</sub>O<sub>5</sub> and TiO<sub>2</sub> for Use as High-k Gate Dielectrics, Workbook of the 30th IEEE Semiconductor Interface Specialist Conference, Charleston, SC, USA
(Accessed December 3, 2023)