Tailored and deep porosification of LTCC substrates with phosphoric acid
Tailored and deep porosification of LTCC substrates with phosphoric acid
复制标题
DOI：
10.1016/j.jeurceramsoc.2019.04.026
复制
发表时间：
2019-08
影响因子：
5.7
通讯作者：
A. Hajian;S. Smetaczek;Christopher Zellner;M. Stöger-Pollach;T. Konegger;A. Limbeck;U. Schmid
中科院分区：
文献类型：
--
作者：
A. Hajian;S. Smetaczek;Christopher Zellner;M. Stöger-Pollach;T. Konegger;A. Limbeck;U. Schmid
低温共烧陶瓷(LTCC)作为一种先进的电子元器件组装技术，在无线通信、汽车雷达等领域有着广泛的应用前景。然而，在高频下工作的微机械器件的精确设计需要具有定制介电系数区域的基板。通过湿法化学腐蚀在衬底中引入可控孔隙率是一种很有前途的降低介电常数的方法，这种方法可以应用于商业上的LTCC，而不需要改变它们的成分或烧结工艺。在本研究中，通过选择性地溶解黑云母相，可以在保持表面质量的同时实现非常深的孔洞化(迄今报道的最高)。此外，通过仔细选择刻蚀参数，可以精细地调整孔化深度，从而降低介电常数。利用激光烧蚀电感耦合等离子体质谱对衬底的化学成分进行了研究。
Low temperature co-fired ceramics (LTCC) as an advanced technology for robust assembly of electronic components, has attracted significant attention in a wide application range such as in wireless communication or automotive radar systems. However, accurate designs of micromachined devices operated at high frequencies require substrates with regions of tailored permittivities. Introduction of controlled porosity into the substrate via wet-chemical etching procedure, is a promising approach for permittivity reduction which can be applied to commercially available LTCC without necessitating to alter their composition or sintering process. In the present study, by selective dissolution of celsian phase a very deep porosification (highest reported so far) could be realized while preserving the surface quality. Also, by a careful selection of the etching parameters, the depth of porosification and hence the permittivity reduction can be delicately tailored. Laser ablation inductively coupled plasma mass spectrometry was used for the investigation of chemical compositions of substrates.