Translator Disclaimer
6 December 2004 A benchmark investigation on cleaning photomasks using wafer cleaning technologies
Author Affiliations +
As new technologies are developed for smaller linewidths, the specifications for mask cleanliness become much stricter. Not only must the particle removal efficiency increase, but the largest allowable particle size decreases. Specifications for film thickness and surface roughness are becoming tighter and consequently the integrity of these films must be maintained in order to preserve the functionality of the masks. Residual contamination remaining on the surface of the mask after cleaning processes can lead to subpellicle defect growth once the mask is exposed in a stepper environment. Only during the last several years, has an increased focus been put on improving mask cleaning. Over the years, considerably more effort has been put into developing advanced wafer cleaning technologies. However, because of the small market involved with mask cleaning, wafer cleaning equipment vendors have been reluctant to invest time and effort into developing cleaning processes and adapting their toolset to accommodate masks. With the advent of 300 mm processing, wafer cleaning tools are now more easily adapted to processing masks. These wafer cleaning technologies may offer a solution to the difficulties of mask cleaning and need to be investigated to determine whether or not they warrant continued investigation. This paper focuses on benchmarking advanced wafer cleaning technologies applied to mask cleaning. Ozonated water, hydrogenated water, super critical fluids, and cryogenic cleaning have been investigated with regards to stripping resist and cleaning particles from masks. Results that include film thickness changes, surface contamination, and particle removal efficiency will be discussed.
© (2004) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Louis Kindt, Jay Burnham, and Pat Marmillion "A benchmark investigation on cleaning photomasks using wafer cleaning technologies", Proc. SPIE 5567, 24th Annual BACUS Symposium on Photomask Technology, (6 December 2004);


Back to Top