以聚铝氧烷为铝源,聚硼硅氮烷兼作硼源和硅源,共混得到SiBAlON陶瓷前驱体,经高温裂解得到SiBAlON陶瓷。采用TGA和XRD对SiBAlON前驱体的裂解行为及陶瓷产物晶相结构进行表征。结果表明,Al的引入降低了陶瓷的结晶温度,当陶瓷中的Al含量为10wt%时,1 300℃处理后析出β-Si_3N_4晶体,1 500℃时,陶瓷中的Al和O与无定型的Si-N结合生成出现Si_2N_2O和Si_3Al_3O_(3+1.5x)N_(5-x)结晶,1 700℃时Al和O与结晶的β-Si_3N_4固溶生成β’-SiAlON结晶,最终陶瓷产物晶相组成为Si_2N_2O/Si_3Al_3O_(3+1.5x)N_(5-x)/β’-SiAlON。对陶瓷的介电性能进行研究表明,温度〈1 000℃时,其介电常数和介电损耗较为稳定,分别约为3和〈0.004。
SiBAlON ceramic precursors were prepared by blending polyaluminoxane and polyborosilazane,which were used as aluminum,silicon and boron source,respectively. The precursor could be transformed into SiBAlON ceramic during the pyrolysis process and its pyrolytic behavior and phase composition were studied by TGA and XRD.Results indicated that the phase composition of the ceramic sample is strongly affected by the Al content of the ceramic. The ceramic with a Al content of 10wt% remained amorphous until β- Si_3N_4 initially generated at 1 300℃. Heating to 1 500℃ led to the formation of Si_2N_2O and Si_3Al_3O_(3+1.5x)N_(5-x) via reaction of Al and O with amorphous Si- N.Further heating to 1 700℃ led to the formation of β'- SiAlON via reaction of Al and O with β- Si_3N_4. The obtained SiBAlON ceramic has excellent dielectric property at room and high temperature.