Removal of Organic Wax and Particles on Silicon after Batch type Polishing by Ozonated DI Water

Abstract

To manufacture the wafer used for device chip, several polishing and cleaning process are required. In this study, new concept cleaning process was developed with ozonated DI water (DIO 3 ) to achieve low COO (cost of ownership). Ozone concentration of 55 ppm is used to remove the wax film and particles. A commercial dewaxer was combined with DIO 3 to reduce dewaxing time and SC-1 steps. DIO 3 rinse resulted in less than 50Å of wax thickness while DI water rinse did thicker than 300 Å. Replacing DI rinse with DIO 3 rinse resulted in lower contact angle and completely hydrophilic surface. Optical images of surfaces treated with DIO 3 showed thinner wax layer which indicates no further cleaning steps required. Particle removal efficiency improved further by combining SC-1 cleaning step with DIO 3 rinsing process.