Title :
Dielectric study of thin films of Ta2O5 and ZrO2
Author :
Jonsson, A.K. ; Frenning, G. ; Nilsson, M. ; Mattsson, M.S. ; Niklasson, G.A.
Author_Institution :
Dept. of Mater. Sci., Uppsala Univ., Sweden
fDate :
8/1/2001 12:00:00 AM
Abstract :
Electronic conduction in sputtered Ta2O5 and ZrO2 thin films have been studied using impedance spectroscopy, isothermal transient ionic current, and current-voltage measurements. The dielectric properties of Ta2O5 were shown to be sensitively dependent on deposition parameters with two different frequency responses: a flat loss behavior with very low DC conductivity, or a relaxation peak together with a somewhat higher DC conductivity. ZrO2 has different dielectric properties when fresh, i.e. newly deposited, or aged. A fresh sample arbitrarily can show two different behaviors, consisting of a DC conductivity with a relaxation peak superimposed on it. The DC conductivity shows either of two different values. The aged sample has a lower permittivity and DC conductivity, and the relaxation peak is found at much lower frequencies. Fresh samples of ZrO2 also show switching behavior
Keywords :
dielectric properties; dielectric thin films; ionic conductivity; permittivity; sputtered coatings; tantalum compounds; zirconium compounds; DC conductivity; Ta2O5; Ta2O5 thin films; ZrO2; ZrO2 thin films; aged sample; current-voltage measurements; deposition parameters; dielectric study; electronic conduction; impedance spectroscopy; isothermal transient ionic current; newly deposited samples; permittivity; relaxation peak; sputtered thin films; switching behavior; Aging; Conductivity; Current measurement; Dielectric losses; Dielectric measurements; Dielectric thin films; Electrochemical impedance spectroscopy; Frequency; Isothermal processes; Sputtering;
Journal_Title :
Dielectrics and Electrical Insulation, IEEE Transactions on
