Read/Search this Article
In this work, two methods are combined in order to provide 25 nm contact holes at 90 nm pitch: the line/space double exposure immersion lithography and the plasma-assisted shrink technology. We first present the line/space imaging method with negative tone development to create directly 45 nm CH at 90 nm pitch. Then, we discuss plasma-assisted shrink technology and how it applies to these small contacts. Plasma-assisted shrink technology relies on running a fast cyclic process, where plasma polymers are deposited on the photoresist mask, then subsequently redistributed over the features sidewalls, allowing in final a diameter reduction of approximatively 50%. Finally, for the metal-hard-mask patterning approach, the dielectric etch challenges driven by the dimensional scaling are analysed and discussed.
- Jpn J Appl Phys
Jpn J Appl Phys 50(8), 08JE07-08JE07-4, 2011-08-25
The Japan Society of Applied Physics