Optimisation of the preclean II bell jar surface for reduction of defect density.
Maung Phone Naing.
Date of Issue2004
School of Mechanical and Aerospace Engineering
Most of the etched materials are adhered on the bell jar surface and some of them are pumped away by the Turbo pump. The bell jar is installed on top of the PCII chamber and the inner surface is under vacuum and the outer one is exposed to the atmosphere. The PCII process take place inside the chamber and it is under vacuum condition. The etched materials do not adheres well onto the bell jar surface due to the improper surface texture and instead fall onto the semiconductor wafer.
Nanyang Technological University