Effect of Additives on Dielectric Loss of AlN Ceramics
The effects of sintering additives on dielectric loss tangent of AlN ceramics were explored. Different amounts of Y2O3 and TiO2 were respectively added as sintering additives to AlN powders and pressureless sintering was performed in a nitrogen flow atmosphere at 1850 °C or 1900 °C for 2 hours. The resulted AlN ceramics became denser when TiO2 addition was more than 0.5 mol%, and a dense sinter with a relative density of 0.987 could be obtained. Tan δ decreased when TiO2 content was more than 0.5 mol% and a tan δ value of as low as 1.0 x 10-3 could be attained.
T. Ohji, T. Sekino and K. Niihara
S. Kume et al., "Effect of Additives on Dielectric Loss of AlN Ceramics", Key Engineering Materials, Vols. 317-318, pp. 845-848, 2006