晶体管封装用陶瓷金属化层的制备与性能研究

发布时间：2018-02-24 09:18

  本文关键词： 封装 活化钼锰法 金属化层 玻璃相 活化剂　出处：《山东大学》2016年硕士论文　论文类型：学位论文

【摘要】：随着半导体器件和电子制造业的发展,人们对半导体晶体管的性能和可靠性都有了更高的要求,半导体器件的封装也越来越受到重视。尽管电子封装技术及材料整体向小型化、高性能、高可靠性和低成本的方向发展,但是在部分军用及航空航天用晶体管的生产中,金属封装仍被视为保证器件气密性的最佳选择。国内生产的金属管壳,在陶瓷绝缘子和引线的封接处容易出现气密性问题,影响了晶体管封装的可靠性。因此,研究和设计金属化配方及烧结工艺,制备出致密、封接性能好的金属化层,改善氧化铝陶瓷金属化工艺,对于国内半导体封装产业的发展具有很大意义。本课题利用活化钼锰法在氧化铝陶瓷上制备金属化层,并对金属化层的相组成、微观组织、结合界面、抗拉强度等性能进行研究,通过改变钼粉配比,确定金属化膏剂的基本体系,并对其烧结工艺进行优化。通过添加活化剂氧化物BaO和ZrO2,研究活化剂添加量对金属化层性能的影响,并对其活化机理进行分析。试验结果表明,玻璃粉中SiO2、MnO和Al2O3的质量比为50：35：15时,高温烧结时可以生成较好的玻璃相,不会析出MnAl2O4、Mn2Si04和MnSiO3等晶体。金属化层的性能与膏剂配方和烧结温度有关,钼粉含量为75 wt.%、烧结温度为1400℃下制备的金属化层性能最好,抗拉强度可以达到106MPa。配方中钼粉含量过低时,金属化层中含有过多的玻璃相,影响焊料对金属化层的铺展润湿,金属化层的抗拉强度下降,钼粉含量过高时,玻璃相形成和迁移的太少,金属化层中存在较多气孔而不致密,也会降低封接后抗拉强度；提高烧结温度可以促进玻璃相的形成和迁移,制备出更致密的金属化层,陶瓷和金属化层的结合也更紧密,金属化层的抗拉强度较高,但烧结温度过高时,过多的玻璃相迁移到表面并影响焊料的铺展润湿,金属化层的抗拉强度降低。金属化配方中加入BaO和ZrO2都具有改善金属化层性能的作用,在M3配方中添加BaO的量为1.5wt.%时,活化效果最好,金属化层的抗拉强度可以达到138MPa; ZrO2的添加量为0.5wt.%时效果最好,金属化层的抗拉强度达到了121MPa。但二者的活化机制是有区别的,BaO是通过降低金属化层中玻璃相的黏度,促进玻璃相在陶瓷和金属化层中互相扩散迁移,来达到改善金属化层性能的目的,添加量较少时,制备出的金属化层更加致密,陶瓷和金属化层结合的更紧密,金属化层的抗拉强度提高,添加量过多时,金属化层中过多的玻璃相不利于焊料的铺展润湿,降低封接后的抗拉强度；ZrO2则是通过提高玻璃相的强度来改善金属化层的性能,提高金属化层的抗拉强度,但添加量过多时会影响玻璃相对陶瓷的浸润,并抑制陶瓷和金属化层中玻璃相的互相扩散迁移,制备出的金属化层致密性较差,与陶瓷之间的渗透结合不充分,抗拉强度降低。不同的活化剂需要根据它们的作用机理,合理选择添加量。
[Abstract]:With the development of semiconductor devices and electronic manufacturing, people have higher requirements for the performance and reliability of semiconductor transistors, and more and more attention has been paid to the packaging of semiconductor devices. High performance, high reliability and low cost development, but in the production of some military and aerospace transistors, metal packaging is still regarded as the best choice to ensure the airtightness of devices. The sealing of ceramic insulators and leads is prone to the problem of airtightness, which affects the reliability of transistor packaging. Therefore, the metallization formulation and sintering process are studied and designed to prepare a dense metallized layer with good sealing performance. Improving the metallization process of alumina ceramics is of great significance to the development of semiconductor packaging industry in China. In this paper, the metallized layer is prepared on alumina ceramics by activated molybdenum manganese method, and the phase composition and microstructure of the metallized layer are also studied. Combined with the properties of interface and tensile strength, the basic system of metallized paste was determined by changing the proportion of molybdenum powder. The effects of the amount of activator on the properties of metallized layer were studied by adding activator oxide BaO and ZrO _ 2, and the activation mechanism was analyzed. When the mass ratio of Sio _ 2 and Al2O3 in glass powder is 50: 35: 15, better glass phase can be formed when sintering at high temperature, and MnAl _ 2O _ 4, mn _ 2Si _ 4 and MnSiO3 crystals will not precipitate. The properties of metallized layer are related to paste formulation and sintering temperature. The metallized layer prepared at the sintering temperature of 1400 鈩，

本文编号：1529696