Hisashi Kasahara

A comprehensive reticle handling and storage approach for optimized fab yields

In the field, each customer uses their owned designed reticle case as for shipping, storage. To modify the case is so expensive that it is very difficult to improve, especially in time respect. At the blank suppliers, they ship their mask blanks packing into their owned designed multiple shipper, however the market needs single shipper with next generation blanks to prevent from particle and outgas of case material damage. At the mask shops, most of them use MP567 (Trade mark of Dainichi Shoji K.K.) single case which was designed about 15years ago to ship their products to their customers. It is not designed for robot handling, so contamination from manual handling makes reticle damaged. Adhesive tape is also required to seal it, so chemical contamination will be occurred on quartz glass, i.e. haze. At the IC fabs, scanner case such as Nikon, Canon and ASML case is the most common in their process. However these cases are not airtight, so they cannot be handled under class 10000 circumstances. RSP (Reticle SMIF Pod) has a capability of automatic transportation, however it is not airtight case. We develop new mask case named Universal Reticle Pod (URP) at affordable price, airtight and chemical tight so as to be used as shipping, storage and process case. We evaluate it as blanks shipping case, so we would like to report its results.