SOME DIELECTRIC PROPERTIES OF TANTALUM PENTOXIDE

Journal Article · Sat Feb 15 04:00:00 EST 1964 · Journal of Chemical Physics (U.S.)

DOI:https://doi.org/10.1063/1.1725287· OSTI ID:4116611

Pavlovic, A S

The dielectric constant and dissipation factor of BETA - and alpha - Ta/sub 2/O/sub 5/ ceramics and of plates cut from a boule of alpha Ta/sub 2/O/ sub 5/ were measured from 77 to 373 deg K over a frequency range from 100 cps to 100 kc/sec. BETA -Ta/sub 2/O/sub 5/ ceramics behave as typical dielectric materials. On the other hand, alpha -Ta/sub 2/O/sub 5/ ceramics exhibit large migrational losses, similar to those found in glasses, due to the migration of the tantalum ion through the structure. The activation energy Q of the process is estimated to be about 0.64 ev, in close agreement with 0.71 ev found from the formation of anodic films on tantalum. This and other facts suggest that anodic tantalum pentoxide is similar to that of the alpha form. A large relaxation peak is found in the data for boule alpha -Ta/sub 2/O/sub 5/ material having Q = 0.2 ev and T/sub o/ = 10/sup -10 sec. This peak must arise from a large deformation of the structure to account for such a large relaxation time and large dielectric constant peak. (auth)

• Research Organization: West Virginia Univ., Morgantown
• Sponsoring Organization: USDOE
• NSA Number: NSA-18-012078
• OSTI ID: 4116611
• Journal Information: Journal of Chemical Physics (U.S.), Journal Name: Journal of Chemical Physics (U.S.) Vol. Vol: 40; ISSN JCPSA
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

ALLOTROPY
CERAMICS
CHEMISTRY
CONFIGURATION
DIELECTRICS
ELECTROPHORESIS
ENERGY
FREQUENCY
LOSSES
LOW TEMPERATURE
MEASURED VALUES
MOLECULES
PLATES
RELAXATION
TANTALUM OXIDES
TEMPERATURE