SBIR Phase I: Clean Tool: A unified approach to wafer cleaning

这个小型企业创新研究(SBIR)第一阶段项目将开发一种新的晶圆清洁工具，该工具将在半导体工艺的每一个清洁步骤中都有用。它将使用一种环保的声学技术，只使用干净的水和无声的声音。该工具将通过使用UPW(超纯水)同时检测并清除晶片中的颗粒来清洁晶片，直到所有颗粒都已被去除。它的新奇之处在于，这将是第一个采用终点确定清洁的工具。然后，它将短暂地冲洗晶片，并在同一工具中将其烘干。在这种简化的流程中，完全清洁的晶圆将更快、更经济地用于下一步工艺，并且使用更少的洁净室空间。清洗机构依靠构造性控制的声学微空化，精确地在颗粒位置将颗粒排出；同时检测空化内爆回声，并跟踪清洗。该工具将适用于所有100 nm以下的技术节点。它将能够检测到远低于50 nm的晶片上颗粒。除了半导体应用之外，该项目的更广泛的影响/商业潜力将是光刻掩模、MEMS、太阳能电池、平板显示器、HDD和精密光学的精密清洗。最终，构造性控制微空化的原理依赖于控制最基本的相变过程，即控制成核--在固相附近将液体转化为气体的能力。这应该在各种化学加工中有更广泛的应用，例如在控制化学反应和核反应堆的沸腾过程中。这种声学成核控制的研究可以形成一个活跃的研究和教育领域。被丢弃的晶圆相当于对包括能源、材料和生产时间在内的主要资源的巨大浪费；它还会通过产生的废水和废料进一步造成环境退化。使用清洁工具来防止这种晶圆损失直接造福于整个社会。

This Small Business Innovation Research (SBIR) Phase I project, will develop a new kind of wafer cleaning tool that will be useful at every cleaning step in semiconductor processing. It will use an environmentally friendly, acoustic technology that uses only clean water and silent sound. The tool will clean a wafer by simultaneously detecting and dislodging the particulates from the wafer using UPW (ultra pure water) until all particulates have been removed. Its novelty is that this will be the first tool incorporating the endpoint determined cleaning. It will then rinse the wafer briefly and dry it in the same tool. In this streamlined sequence, a fully clean wafer will be available for the next process step much more quickly, much more economically, and in much less cleanroom space. Cleaning mechanism relies on constructively controlled acoustic microcavitation precisely brought about at the particle location to dislodge the particle; the cavitation implosion echo is simultaneously detected and cleaning kept track of. This tool will be applicable to all sub-100nm technology nodes. It will be able to detect on-wafer particulates well below 50nm. The broader impact/commercial potential of this project beyond semiconductor application will be in precision cleaning of lithography masks, mems, solar cells, flat panel displays, HDDs, and precision optics. Ultimately, the principle of constructively controlled microcavitation relies on controlling the very fundamental process of phase change, the control of nucleation -- the ability to convert a liquid into a gas in the vicinity of a solid phase. This should have much wider applications in a variety of chemical processing, e.g. in the control of the boiling processes in chemical and nuclear reactors. The study of this acoustically mediated nucleation control could form an active field/area of research and education. Rejected wafers amount to a colossal waste of prime resources including energy, material, and productivity time; it further amounts to environmental degradation through the effluents and scrap generated. The use of clean tool to prevent such wafer loss directly benefits the society at large.