Preparation and characterization of CaO-Al₂O₃-SiO₂ glass/fused silica composites for LTCC application

详细信息	查看全文 | 推荐本文 |

• 作者：Guobin Xia ; Lvting He ; De&rsquo ; an Yang ; ^{dayang@tju.edu.cn}
• 关键词：Composites ; Sintering ; X-ray diffraction ; Thermal expansion ; LTCC
• 刊名：Journal of Alloys and Compounds
• 出版年：2012
• 期刊代码：45_09258388
• 类别：ms
• 出版时间：5 August, 2012
• 卷：531
• 期：Complete
• 页码：70-76
• 文件大小：1338 K

摘要

A new glass/ceramic system containing low-softening CAS (CaO-Al₂O₃-SiO₂) glass and high-softening fused silica for LTCC (low temperature cofired ceramics) application was studied. The compositions of CAS glass were properly designed from the viewpoint of achieving low thermal expansion. XRD results of both the composites and pure CAS glasses showed that cristobalite phase was significantly reduced by increasing the sintering rate and shortening the soaking time. Sufficient densification was achieved at 900 掳C, when the glass content increased to 70 wt%. In the present study, the mechanism of viscous flow dominated the sintering process. The results of thermal expansion constant (TEC) of the prepared glasses were in the range of (5.18-6.30) 脳 10^鈭? 掳C^鈭?, close to the designed value (4.5 脳 10^鈭? 掳C^鈭?). The 70 wt%CAS glass/fused silica composites sintered at 900 掳C with a sintering rate of 5 掳C/min and a soaking time of 2 h exhibited high TECs in the range of (12.32-16.96) 脳 10^鈭? 掳C^鈭?. However, TEC significantly dropped when the sintering rate was increased to 8 掳C/min and the soaking time was shortened to 1 h. The 70 wt%CAS Glass C/fused silica composite exhibited a low TEC of 4.80 脳 10^鈭? 掳C^鈭?, close to that of silicon (3.1 脳 10^鈭? 掳C^鈭?), and a low dielectric constant of 4.7. Both the TEC and the dielectric constant of the composite were on the lower side of that reported for commercial products, indicating its suitability for LTCC application.