Plasma processing method and plasma processing system
Provided is a plasma processing method performed with a plasma processing apparatus including a chamber. The method includes: (a) providing a substrate in the chamber, the substrate having an organic film and a mask on the organic film, the mask including a silicon-containing film and a carbon-containing film on the silicon-containing film; and (b) forming a plasma from a processing gas in the chamber, the processing gas including an oxygen-containing gas and a gas containing Si or W and a halogen. (b) includes: (b1) forming a protective film on at least the carbon-containing film of the mask; and (b2) etching the organic film through the mask having the protective film formed thereon.
1 . A plasma processing method performed with a plasma processing apparatus including a chamber, comprising:
(a) providing a substrate in the chamber, the substrate having an organic film and a mask on the organic film, the mask including a silicon-containing film and a carbon-containing film on the silicon-containing film; and
(b) forming a plasma from a processing gas in the chamber, the processing gas including an oxygen-containing gas and a gas containing Si or W and a halogen, (b) including:
(b1) forming a protective film on at least the carbon-containing film of the mask; and
(b2) etching the organic film through the mask having the protective film formed thereon,
wherein the (b1) continues after a start of the (b2), and the protective film formed in the (b1) on an entirety of a side surface of the carbon-containing film is thinner than an entirety of the protective film formed on a top surface of the carbon-containing film.
2 . The plasma processing method according to claim 1 , wherein the gas containing Si or W and a halogen includes at least SiCl 4 , and a flow rate of the SiCl 4 is 4 vol % or more and less than 5 vol % relative to a total flow rate of the process gas.
3 . The plasma processing method according to claim 1 , wherein the gas containing Si or W and a halogen includes at least WF 6 .
4 . The plasma processing method according to claim 1 , wherein the protective film includes silicon or tungsten.
5 . The plasma processing method according to claim 1 , wherein the silicon-containing film comprises a SiON film.
6 . The plasma processing method according to claim 1 , wherein the carbon-containing film comprises a spin on carbon (SOC) film or a bottom anti-reflection coating (BARC) film.
7 . The plasma processing method according to claim 1 , wherein the oxygen-containing gas includes at least one selected from the group consisting of O 2 , O 3 , CO, CO 2 , and H 2 O.
8 . The plasma processing method according to claim 1 , wherein the processing gas includes a sulfur-containing gas.
9 . The plasma processing method according to claim 8 , wherein the sulfur-containing gas includes COS or SO 2 .
10 . The plasma processing method according to claim 1 , wherein the processing gas further includes a halogen-containing gas.
11 . The plasma processing method according to claim 1 , wherein the (b1) continues immediately after the start of the (b2).
12 . A plasma processing method performed with a plasma processing apparatus including a chamber, comprising:
(a) providing a substrate in the chamber, the substrate having an organic film and a mask on the organic film, the mask including a carbon-containing film; and
(b) forming a plasma from a processing gas in the chamber, the processing gas including an oxygen-containing gas and a gas containing Si or W and a halogen, (b) including:
(b1) forming a protective film on at least the carbon-containing film of the mask; and
(b2) etching the organic film through the mask having the protective film formed thereon,
wherein the (b1) continues after a start of the (b2), and the protective film formed in the (b1) on an entirety of a side surface of the carbon-containing film is thinner than the protective film formed on an entirety of a top surface of the carbon-containing film.