硼磷硅玻璃缺陷分析与研究

Analysis and Research Results of BPSG on Abnormal Problem

在晶圆制造中广泛运用掺杂有硼和磷的二氧化硅即硼磷硅玻璃作为绝缘介质,一般用于金属布线前的绝缘层。掺杂硼磷的作用是降低回流温度,减少热预算。但在实际运用中,由于硼磷硅玻璃性质不够稳定,常常受到环境的影响,其中的三氧化二硼和五氧化二磷容易和空气中的水汽反应生成硼酸和磷酸继而形成缺陷,造成电路短路,最终导致产品低良率,给公司造成损失。文章就硼磷硅玻璃受环境影响的异常现象进行分析研究,找到缺陷形成的根本原因及预防方法。

In wafer manufacturing process, BPSG（Boron and Phosphorus Silicon Glass）film which doped boron and phosphorus is used as dielectric film widely. Normally BPSG film is used in pre metal dielectric layer. The function of doped boron and phosphorus is to reduce reflow temperature and decrease thermal budget. But in fact its property is unstable for environment effect .B203 and P205 in BPSG film react with water vapor easily and form H3BO3 and HaPO4.As a result, BPSG film will produce defect, induce short circuit ,cause product low yield and diminish the company profit. So at here, I will share my analysis and research results on BPSG abnormal case due to environment effect.