Turn around time/cycle time is a key success criterion in the semiconductor photomask business. Therefore, global mask
suppliers typically allocate work loads based on fab capability and utilization capacity. From a logistical point of view,
the manufacturing location of a photomask should be transparent to the customer (mask user).
Matching capability of production equipment and especially metrology tools is considered a key enabler to guarantee
cross site manufacturing flexibility. Toppan, with manufacturing sites in eight countries worldwide, has an on-going
program to match the registration metrology systems of all its production sites. This allows for manufacturing flexibility
and risk mitigation.In cooperation with Vistec Semiconductor Systems, Toppan has recently completed a program to
match the Vistec LMS IPRO systems at all production sites worldwide. Vistec has developed a new software feature
which allows for significantly improved matching of LMS IPRO(x) registration metrology tools of various generations.
We will report on the results of the global matching campaign of several of the leading Toppan sites.
The development of the 45-nm node manufacturing process at leading edge mask shops is nearly finished. In order
to reach the required registration measurement performance with a precision to tolerance value of P/T=0.25,
the measurement error may not exceed 1.2 nm according to ITRS roadmap. This requires the latest generation
of registration measurement tools. In addition, the demand for measuring very small features increases - for
standard pattern placement measurements, as well as special engineering tasks, e.g., the position measurement
of single contact holes.
In this work, the error of pattern placement measurement on an LMS IPRO4 is determined using an analysis
of variance methodology (ANOVA). In addition we analyze the capability as a function of the critical dimension
(CD) of the registration feature. The results are compared to the previous tool generation.