DEMCON has been developing and building highly complex qualification tools to support both development and production at ASML for many years. One example is the Position Module Qualification Tool Mk 4 (PMQT4). This is a fourth-generation qualification tool for the wafer positioning module of an ASML lithography machine, in this case the NXT platform.
The DEMCON qualification systems have the same mechanical interface as the ASML machines and are equipped with complex control software for real-time regulations in several degrees of freedom. They test and qualify a large number of properties, in the magnetic, electrical, mechanical, thermal and software (control) domains, of the connections of pipelines and cables to the highly precise specifications for the dynamic behaviour.
Qualification of a position module with the PMQT4 takes a few hours. In that time, more than 200 parameters are qualified, such as positioning accuracies, rigidity, engine constants and connectivity (electrical, pneumatic and hydraulic). DEMCON opted for a complete redesign, with a view to improving the reliability and acceleration of the development process at ASML. Thus the number of connectivity tests was expanded, the reliability of the tool was increased further and the ergonomics (accessibility of the tool) were improved. Once again, DEMCON was also able to conceive smart solutions for the ultimate test, the qualification of the qualification tool. As with almost all ASML projects, the development took place in close cooperation with ASML. Engineers from both companies work together closely throughout the project cycle in order to guarantee a good result and prevent any negative surprises.
For accurate positioning over a wide range, the positioning module has separate stages for long stroke and short stroke movements. DEMCON has designed the PMQT4 to enable the long and the short stroke to be tested separately. In the development phase, this shortens the design process. After all, designers of one stage no longer have to wait until a prototype for the other stage is available, but can start testing right away.
DEMCON performs projects for building qualification tools on a turn-key basis. Because these tools are deployed in production at ASML, they must be fast and simple to operate and lead to as little downtime as possible. To that end, DEMCON provides for the maintenance and offers a 24/7 service. In this way, DEMCON manages to qualify itself time and again as a reliable partner of ASML.
