Electrical properties of silver-tantalate-niobate thick films

Silver tantalate niobate (ATN) thick films have been prepared by screen printing technique in order to investigate their potential for application in tunable high frequency devices. The permittivity, losses and tunability of AgTaxNb1-xO3 thick films (0 > x > 0.4) printed on Al2O3 substrates have been measured at low frequency in a temperature range from -150degreesC to 120degreesC and at 10 GHz, in a temperature range from -40degreesC to 120degreesC. The main focus is put on the M1-M2 phase transition which exhibits a ferroelectric relaxor like character. In the range of this phase transition the permittivity of ATN thick films shows tunability of 18%. In comparison to Barium Strontium Titanate permittivity is relatively low, e.g. epsilon=180 for AgTa0.1Nb0.9O3 at room temperature.