氮化铝陶瓷中氧质量分数及其分布的测定

Determination of oxygen mass fraction and distribution in aluminum nitride ceramics

氮化铝陶瓷以其优异的导热性能成为集成电路、半导体及大功率器件的重要封装材料,然而杂质氧含量(质量分数)直接影响着氮化铝陶瓷的导热性能。准确测定氮化铝陶瓷内氧含量(质量分数)及其分布十分重要。在惰性熔融红外吸收法基础上,对氮化铝陶瓷中不同形式氧含量分析方法进行了研究。通过步进式升温模式对样品中的表面吸附氧、晶界氧和晶格氧的氧含量进行分开测定,探讨了坩埚、裕料的选择及测试过程对结果的影响,分析了石墨粉含量对晶界氧的释放作用,最终优化了升温程序、加粉顺序以及称样量。通过氮化铝陶瓷样品多次平行试验对测定方法的准确性进行了验证,实测晶界氧和晶格氧含量的相对标准偏差分别为4.5%、8.5%,能够满足相关科研要求。

Aluminum nitride ceramics have become the important packaging materials for integrated circuits,semiconductors,and high-power devices due to the excellent thermal conductivity.The oxygen impurities in aluminum nitride ceramics directly affect the thermal conductivity.Thus,it is important to accurately determine the oxygen content(mass fraction)and distribution in aluminum nitride ceramics.Based on the inert melting infrared absorption method,the analysis methods of oxygen mass fraction in different forms in the aluminum nitride ceramics were studied.The mass fraction of surface adsorption oxygen,grain boundary oxygen,and lattice oxygen in the nitride ceramics was measured separately by the stepped heating method.The influence of crucible and auxiliary material selection on the measurement process and test results was discussed.The effect of graphite powder content on the release of grain boundary oxygen was analyzed.Finally,the heating program,the order of adding powder,and weight were optimized.The measurement method accuracy was verified by the multiple parallel tests on the aluminum nitride ceramics.In the results,the relative standard deviations of the measured grain boundary oxygen and lattice oxygen content are 4.5% and 8.5%,respectively,meeting the requirements of the relevant scientific research.