Photomask automation improvement to eliminate manufacturing errors

Photomask manufacturing automation has lagged semiconductor wafer process automation development. In a highly complex wafer fab, data automation and advanced process control techniques are required. Given limited demand, photomask equipment manufacturers have not unilaterally made the investment necessary to implement a standardized data flow protocol which would allow photomask process automation enhancements. Surveys indicate that significant photomask yield loss is attributed to manufacturing and administrative errors. By working with individual photomask equipment suppliers and through internal application development, IBM photomask manufacturing automation has eliminated nearly all manufacturing and administrative errors. Some examples of processes that were automated over the past several years are process routing selection, photomask yield prediction, linkage of photomask blank to mask build part number, automated recipe and setup download and dispositioning criteria, statistical analysis of process parameters and defect density, defect information management and automated data upload for photomask and wafer engineering use. Project highlights will be discussed and the case will be made for standardization of data flow protocol and for further photomask process automation improvements.