Non-ohmic behavior of Nb-doped SrTiO3 grain boundary layers

Abstract

The non-ohmic behavior of a single grain junction of Nb-doped SrTiO3 has been investigated. The specimen was sintered at 1570 degrees C for 4 h in air. Silk screen method was applied to form electrodes across grain boundary for measuring the breakdown voltage. The breakdown voltage was found to; be about 7 V and this result was comparable to the calculated value from the breakdown voltage of bulk specimen. The dielectric constant, dielectric loss and insulating resistance of 0.4 mol% Nb2O5 doped SrTiO3 were 80,000, 2.5% and 7 x 10(8) Omega. The nonlinear coefficient (alpha) was determined to be about 9 from I-V characteristics.