Yield Loss Due to the Interaction Between Dissolved Oxygen in DI Water and Megasonic in Final Rinse Process

This proposed paper presents an intriguing case study on yield loss investigation and failure mechanisms in semiconductor manufacturing. This study is significant because it uncovers a failure mode that is not typically anticipated, providing valuable insights for selecting cleaning process recipes, especially for smaller features. In semiconductor manufacturing, maintaining lower dissolved oxygen (DO) levels in deionized water (DIW) is essential to eliminate charging and contamination-related failures. Similarly, the application of megasonic power in wet cleaning recipes is generally employed to achieve better cleaning and higher yield. However, these practices may not be advantageous in all scenarios, particularly when interacting with smaller geometries. We present a yield loss mechanism resulting from the interaction between lower DO levels in DIW and megasonic cleaning in RCA processes. This interaction can lead to significant failures, particularly in smaller emitter cavities, where the effects of surface tension and capillary forces become more pronounced. The findings from this study are essential for enhancing the reliability and yield of semiconductor devices. Implementing strategies to control DO levels and megasonic treatment parameters can significantly improve the effectiveness of the cleaning process and ensure the quality of the manufactured products.