No abstract

No abstract

MEMS manufacturing in general and the litho step in particular could benefit tremendously from an enhanced focus range of waferstepper alignment systems. This would help the MEMS community to cope with large substrate topography or extreme thick resist films. In this study the performance range over which of the alignment system of an ASML PAS5000/50 system operates has been investigated.A test device that requires bulk micro machining was designed and processed. The required front to backwafer alignment (FTBA) was performed on alignment markers in cavities etched through a 100mm wafer. On the test device the FTBA overlay was measured electrically as well as optically using the metrology capability of the stepper alignment system. The results obtained demonstrate the capabilities of an existing alignment system to deal with high topographies. The overlay errors observed were dominated by the bulk micro machining processing.

No abstract

No abstract