半导体用高纯钨靶材的制备技术与应用

Preparation Technology and Application of High Purity Tungsten Target for Semiconductor

难熔金属钨及钨合金由于具有高温稳定性好、电子迁移抗力高以及电子发射系数高等优点,在半导体大规模集成电路制造过程中有着广泛的应用。本文对半导体用高纯钨及钨合金靶材的应用领域、性能要求以及制备方法进行了详细的分析,并对其发展趋势进行了展望。高纯钨及钨合金靶材主要用于制造半导体集成电路的栅电极、连接布线、扩散阻挡层等,对材料的纯度、杂质元素含量、致密度、晶粒尺寸及晶粒组织均匀性等方面都有着极高的要求。高纯钨及钨合金靶材主要采用热压、热等静压等方式来制备,采用中频烧结+压力加工的方式可以制备出高纯度、高致密度的钨靶材,但晶粒尺寸及晶粒组织均匀性控制方面,与热等静压制备的钨靶仍有一定的差距。

Tungsten and tungsten alloys are widely applied in the manufacturing of large-scale integrated circuits due to their high temperature stability, high electron transfer resistance and high electron emission coefficient. In this research,the application area, performance requirements and preparation methods of high purity tungsten and tungsten alloy targets for semiconductor were analyzed in detail, and their development trends were prospected. High purity tungsten and tungsten alloy targets are mainly used to fabricate gate electrode, interconnect and diffusion barrier for semiconductor integrated circuits; their requirements for the purity, impurity content, density, grain size and uniformity of grain structure were high.High purity tungsten and tungsten alloy targets are mainly prepared by hot pressing, hot isostatic pressing and so on.Tungsten target with high purity and high density can be prepared by intermediate frequency sintering and pressure processing, but its grain size and grain homogeneity are not very well compared with the tungsten target produced by hot isostatic pressing.