CPC H01L 21/0332 (2013.01) [H01L 21/02164 (2013.01); H01L 21/0337 (2013.01); H01L 21/0338 (2013.01); H01L 21/302 (2013.01); H01L 21/3065 (2013.01); H01L 21/308 (2013.01); H01L 21/3081 (2013.01); H01L 21/3086 (2013.01); H01L 21/3088 (2013.01); H01L 21/31116 (2013.01); H01L 21/32139 (2013.01); H01L 21/823431 (2013.01); Y10S 438/947 (2013.01)] | 20 Claims |
1. A method comprising:
depositing a hard mask over a target layer, wherein depositing the hard mask comprises:
depositing a first oxide hard mask layer having a first density; and
depositing a second oxide hard mask layer over the first oxide hard mask layer,
the second oxide hard mask layer having a second density greater than the first density;
forming a plurality of mandrels over the hard mask;
forming a plurality of spacers on sidewalls of the plurality of mandrels;
removing the plurality of mandrels;
transferring a pattern the plurality of spacers to the hard mask; and
using the hard mask to define a pattern in the target layer.
|