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

This Small Business Innovation Research (SBIR) Phase II project aims to develop a single wafer processing clean tool for semiconductor wafer cleaning at all stages of wafer processing. The method relies on using acoustically controlled micro-cavitation to remove on-wafer particles. This is a chemical-free cleaning method, using ultra-pure water as the only processing fluid. During cleaning the particles will be counted as they get removed. The cleaning is deemed complete when there remain no more particles to be removed. The wafer will then be rinsed and dried in the same tool. This project is expected to provide a one-at-a-time wafer cleaning method with all the four functionalities of cleaning, inspection, rinsing and drying accomplished in a single setting. The broader/commercial impacts of this project will be the potential to provide a complete environmentally-friendly solution to the wafer cleaning predicament. Cleanliness is a critical requirement in semiconductor manufacturing that directly impact the chip yields. Among all processing steps in semiconductor manufacturing, approximately one in every five processing steps is wafer cleaning. Perfect wafer cleaning is a significant, yet unsolved, problem in semiconductor industry, and the need is becoming more urgent as the technology moves towards sub-50nm design nodes. In this project, a wafer-cleaning tool will be developed to address this market need. This tool will also be useful in precision cleaning needed in the cleaning of lithography masks, Microelectromechanical Systems (MEMS), solar cells, flat panel displays, and hard disk drives (HDDs).