CMP磨料系统中大尺寸微粒的过滤技术(英文)

Proper Filtration Removes Oversized Particles from CMP Slurry Systems

单步循环过滤,用来去除胶体硅基化学机械抛光(CMP)磨料中尺寸过大的微粒。已证实适当的过滤获得了尺寸过大粒子的快速去除,而不改变CMP磨料中固体粒子浓度的百分比。为模拟CMP磨料分配系统的粒子减少开发了数字模型。这些模型预测了粒子浓度与流速、过滤器的粒子去除效率及过滤时间的关系。这些模型表明,为获得尺寸过大粒子的快速去除,流速是最关键的参数。预先过滤的主要作用是截获部分尺寸过大的粒子,并保护最终过滤不被过早的堵塞,以便提供过滤器最大的使用寿命。根据有限数据的检验,循环流程模型足以预测粒子浓度形貌图。归根结底,最佳过滤器的选择决定了流速、过滤器的粒子去除效率、过滤方案(单步与多步过滤)和过滤器的使用寿命。

Single stage re-circulation filtrations were performed to remove oversized particles from colloidal silica based Chemical-Mechanical Polishing(CMP)slurry.Proper filtration was demonstrated to achieve rapid removal of oversized particles while not altering the percent solids of the CMP slurry.Mathematical models were developed to simulate particle reduction in CMP slurry distribution systems.The models pre-dict particle concentration as a function of the flow rate,the particle removal efficiency of the filter,and fil-tration time.The models show that flow rate is the most critical parameter in order to achieve rapid removal of oversized particles.The major role of pre-filtration is to capture a portion of the oversized particles and protect the final filtration from premature plugging in order to deliver maximum filter service life.Based on examination of the limited data,the re-circulation flow model adequately predicts the particle concentration profile.Ultimately,selection of the optimum filters depends on flow rate,particle removal ef-ficiency of the filter,filtration scheme (single vs.multi-stage filtration),and filter service life.