US 12,106,971 B2
High conductive passivation layers and method of forming the same during high aspect ratio plasma etching
Xiangyu Guo, Bear, DE (US); Kayla Diemoz, Newark, DE (US); and Nathan Stafford, Damascus, OR (US)
Assigned to American Air Liquide, Inc., Fremont, CA (US)
Filed by American Air Liquide, Inc., Fremont, CA (US)
Filed on Dec. 28, 2020, as Appl. No. 17/135,216.
Prior Publication US 2022/0223431 A1, Jul. 14, 2022
Int. Cl. H01L 21/311 (2006.01)
CPC H01L 21/31144 (2013.01) [H01L 21/31116 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A method for forming a patterned structure during an etch process in a substrate in a reaction chamber, the method comprising:
sequentially or simultaneously exposing the substrate to a vapor of an etchant including C4H2F6, an additional etch gas and an additive compound CH3I, the substrate having a film disposed thereon and a patterned mask layer disposed on the film;
activating a plasma to produce an activated C4H2F6, an activated additional etch gas and an activated additive compound; and allowing an etching reaction to proceed between the film uncovered by the patterned mask layer and the activated C4H2F6, the activated additional etch gas and the activated additive compound to selectively etch the film from the patterned mask layer, thereby forming the patterned structure,
wherein the additional etch gas is selected from the group consisting of cC4F8, C4F8, cC5F8, C5F8, C4F6, CF4, CH3F, CF3H, CH2F2, C3HF7, C3F6, C3H2F6, C3H2F4, C3H3F5, C4HF7, C5HF9, C3F8, CF3I, C2F3I, C2F5I, 1-Iodoheptafluoropropane (1-C3F7I), 2-Iodoheptafluoropropane (2-C3F7I), COS, FNO, F—C═N, CS2, SO2, SF6, trans-1,1,1,4,4,4-hexafluoro-2-butene (trans-C4H2F6), cis-1,1,1,4,4,4-hexafluoro-2-butene (cis-C4H2F6), hexafluoroisobutene (C4H2F6), trans-1,1,2,2,3,4-hexafluorocyclobutane (trans-C4H2F6), 1,1,2,2,3-pentafluorocyclobutane (C4H3F5), 1,1,2,2-tetrafluorocyclobutane (C4H4F4), and cis-1,1,2,2,3,4-hexafluorocyclobutane (cis-C4H2F6), and combinations thereof.