Abstract
This paper reports on a novel absorber technology for X-ray stepper masks based on a stabilized tungsten layer. Effective stress reduction (σ⩽10 7 N/m 2) and excellent long term stability (Δσ<5·10 6 N/m 2) are being obtained by sputtering the 0.8 μm thick tungsten layers in the presence of oxygen, and subsequently annealing them in an oxidizing atmosphere. Investigations with respect to microstructure and composition indicate a highly textures W 3O layer, having grain sizes in the order of 60 nm. For etching the W pattern a CF 4 based RIE process has been optimized. In this case a beam lithography in combination with a tri-level system (HPR/SiN/PM15) is being used. W pattern with sub-half micrometer dimensions have been etched with steep edges.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
