It has been still highly required for cost efficient solution with easy operation for full-automated CD measurement for
line width about 500nm up to 5μm on photomask, because it is frequently use such photomask in the process of
manufacturing MEMS sensor for IoT and some devices made in BCD (Bipola CMOS DMOS).
As reply to such demand in photomask manufacturing field, we try to take a low noise digital camera technology and
LED light source for i-line, which are recently developed, into new measuring tool in order to achieve 1nm (3σ)
repeatability for line width measurement between 300nm to 10μm.
In addition, for the purpose of full-automated operation, it is very important to find where an initial target line in dense
pattern. To achieve such auto line detection precisely, we have improved accuracy of high precision stage (20nm as 3σ)
and an alignment algorithm of MEMS Stepper to combine with this tool.
As for user-friendly interface, Windows based software helps a lot for not only the operation but also recipe creation or
edition in Excel. Actually, in the MEMS manufacturing process, there are various photomasks which need to be check
and measure frequently therefore various recipe files are also have to be created and edited frequently..
In order to meet such a requirement in photomask management, we try to make it true by mixing old and new techniques
together into one system, which comes to fully automated and cost efficient tool with 1nm repeatability in CD