US 12,308,212 B2
In-situ adsorbate formation for plasma etch process
Du Zhang, Albany, NY (US); Yu-Hao Tsai, Albany, NY (US); Masahiko Yokoi, Miyagi (JP); Yoshihide Kihara, Miyagi (JP); and Mingmei Wang, Albany, NY (US)
Assigned to Tokyo Electron Limited, Tokyo (JP)
Filed by Tokyo Electron Limited, Tokyo (JP)
Filed on Sep. 30, 2022, as Appl. No. 17/937,151.
Prior Publication US 2024/0112887 A1, Apr. 4, 2024
Int. Cl. H01J 37/32 (2006.01); H01L 21/311 (2006.01)
CPC H01J 37/3244 (2013.01) [H01L 21/31116 (2013.01); H01J 37/321 (2013.01); H01J 37/32724 (2013.01); H01J 2237/2001 (2013.01); H01J 2237/3341 (2013.01); H01J 2237/3345 (2013.01); H01J 2237/3346 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A method of processing a substrate, the method comprising:
flowing dioxygen (O2) and an adsorbate precursor into a plasma processing chamber that is configured to hold the substrate comprising an organic layer and a patterned etch mask, the adsorbate precursor comprising phosphorus;
sustaining an oxygen-rich plasma while flowing the O2 and the adsorbate precursor, oxygen species from the O2 and the adsorbate precursor reacting to form an adsorbate within the oxygen-rich plasma; and
after forming the adsorbate within the oxygen-rich plasma, exposing the substrate to the oxygen-rich plasma to form a recess in the organic layer, wherein, during the exposing, the adsorbate deposits to form a sidewall passivation layer on sidewalls of the recess.
 
8. A method of processing a substrate, the method comprising:
flowing a P-containing adsorbate precursor and a halogen-free gas comprising dioxygen (O2) into a plasma processing chamber that is configured to hold the substrate comprising an organic layer and a patterned etch mask, wherein a ratio of a flow rate of O2 to a flow rate of the P-containing adsorbate precursor is at least 1:1;
sustaining an oxygen-rich plasma while flowing the P-containing adsorbate precursor and the halogen-free gas, oxygen species from the O2 and the P-containing adsorbate precursor reacting under the oxygen-rich plasma to form a P-containing adsorbate; and
exposing the substrate to the oxygen-rich plasma to form a recess in the organic layer, wherein the P-containing adsorbate forms a sidewall passivation layer in the recess.