Properties and Microstructure of Mullite-Glass Ceramics for Multilayer Ceramic Substrates

Author:

Ushifusa N.,Sakamoto K.,Ogihara S.,Fujita T.

Abstract

AbstractMullite (3Al2O3·2SiO2) has a low thermal expansion coefficient and a low dielectric constant making it a favorable material for substrate applications. Sintering of pure mullite ceramics is difficult, however, even above 1700°C. Thus, mullite-glass ceramics containing glass additives (Al2O3-MgO-SiO2 glass) which could be sintered at about 1600°;C were fabricated and their properties were investigated. The ternary system diagram of Al2O3-MgO-SiO2 shows that high SiO2 content glass depos its cristobalite at 200 to 270°C, which causes a substantial volume change, resulting in ceramic substrate cracking. Therefore it is particularly important to prevent crystallization of cristobalite from the glass phase in mullite-glass ceramics. The glass phase softens or partially fuses above 1600°C, and cristobalite formation in the glass phase occurs in the cooling process during firing. In order to obtain good substrates of mullite-glass ceramics, a higher temperature for sintering and faster cooling rate after firing are preferable. Analytical results by X-ray, SEM and EPMA show that mullite dissolves in the glass phase at a higher sintering temperature and more mullite crystallizes in the cooling process with a lower rate. The content of Al2O3 in the glass phase, therefore, increases with the increased sintering temperature and cooling rate, which may restrain crystallization of cristobalite. By adjusting of the composition of mullite and glass phase, mullite-glass ceramics with low dielectric constant (5.9), thermal expansion coefficient (3.5×10−6/°C) close to that of silicon chips, and high bending strength (210MPa) have been developed. These substrates made of mullite-glass ceramics are suitable for mounting silicon devices of computer processors.

Publisher

Springer Science and Business Media LLC

Subject

General Engineering

Cited by 2 articles. 订阅此论文施引文献 订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3