Distortion evaluation of nickel stencil masks with the help of ion proximity exposures and registration measurements on the Leitz LMS- 2000

Abstract

A metrology has been developed to evaluate the distortion of large area stencil masks under ion beam exposure. In an ion projector an ion beam proximity printing was performed with a 85 mm diameter beam of 7.5 keV Helium ions. The gap between Nickel stencil test mask and silicon wafer was 2 mm. Ion beam exposure was done into the surface of 0.8 μm thick AZ-5206 resist with subsequent UV blanket exposure and image reversal development. The Leitz LMS-2000 registration measurement system provided data of the resist pattern to analyse the stencil mask distortion within 25 nm precision and 50 nm accuracy.