Imaging performance of the EUV alpha semo tool at IMEC

Abstract

Extreme Ultraviolet Lithography (EUVL) is the leading candidate beyond 32nm half-pitch device manufacturing. Having completed the installation of the ASML EUV full-field scanner, IMEC has a fully-integrated 300mm EUVL process line. Our current focus is on satisfying the specifications to produce real devices in our facilities. This paper reports on the imaging fingerprint of the EUV Alpha Demo Tool (ADT), detailing resolution, imaging, and overlay performance. Particular emphasis is given to small pitch contact holes, which are a critical layer for advanced manufacturing nodes and one of the most likely layers where EUVL may take over from 193nm lithography. Imaging of contact holes, pattern transfer and successful printing of the contact hole level on a 32nm SRAM device is demonstrated. The impact of flare and shadowing on EUV ADT performance is characterized experimentally, enabling the implementation of appropriate mitigation strategies.