Blakely Sokoloff Taylor & Zafman, LLP
Halogen-free amorphous carbon mask etch having high selectivity to photoresist
In one embodiment of the present invention, a halogen-free plasma etch processes is used to define a feature in a multi-layered masking stack including an amorphous carbon layer. In a particular embodiment, oxygen (O2), nitrogen (N2), and carbon monoxide (CO) are utilized to etch the amorphous carbon layer to form a mask capable of producing sub-100 nm features in a substrate film having a reduced line edge roughness value. In another embodiment, the present invention employs an O2 plasma pretreatment preceding the halogen-free amorphous carbon etch to first form an oxidized silicon region in a patterned photoresist layer to increase the selectivity of the amorphous carbon etch relative to a patterned photoresist layer containing unoxidized silicon.
Applied Materials, Inc.
H H H H H
H01L H01L H01L H01L H01L
inventional inventional inventional inventional inventional
Jong Mun Bryan Y. Jingbao Judy Ajey M.
Kim Pu Liu Wang Joshi