Surface processing method and processing system
There is provided a method of performing a surface processing on a substrate having a metal layer formed on a bottom portion of a recess formed in an insulating film, the method including: supplying a halogen-containing gas into a processing chamber in which the substrate is loaded; and removing a metal oxide from the bottom portion of the recess using the halogen-containing gas.
1 . A method of performing a surface processing on a substrate having a tungsten layer formed on a bottom portion of a recess formed in an insulating film, wherein a surface of the insulating film is directly exposed to a side surface of the recess, the method comprising:
supplying a chlorine-containing gas into a processing chamber in which the substrate is loaded so as to supply the chlorine-containing gas to the recess; and
removing a tungsten oxide film from the bottom portion of the recess using the chlorine-containing gas at an etching rate higher than an etching rate of the insulating film which is exposed to the recess, thereby maintaining a shape of the recess,
wherein the chlorine-containing gas is at least one of tungsten chloride, thionyl chloride, and chlorine fluoride,
wherein the removing the tungsten oxide film is performed using a chemical etching method in which no plasma is used, and
wherein the tungsten oxide film is removed by being directly exposed to the chlorine-containing gas and chemically reacting with the chlorine-containing gas.
2 . The method of claim 1 , wherein the insulating film is a silicon-containing film.
3 . The method of claim 2 , wherein the silicon-containing film is at least one of a silicon oxide film and a silicon nitride film.
4 . The method of claim 1 , further comprising:
after the removing the tungsten oxide film from the bottom portion of the recess, forming a tungsten film on the bottom portion of the recess by alternately supplying a tungsten chloride gas and a hydrogen gas.
5 . The method of claim 4 , wherein in the forming the tungsten film, a chlorine-containing substance, which has remained in the processing chamber as a reaction product generated during the removing the tungsten oxide film, is reacted with the hydrogen gas, and is removed.
6 . The method of claim 1 , further comprising:
embedding a ruthenium from the bottom portion of the recess by supplying a ruthenium-containing gas toward the bottom portion of the recess.
7 . The method of claim 6 , wherein the embedding the ruthenium is performed without having to use an oxygen gas.
8 . The method of claim 6 , wherein the ruthenium-containing gas is any of a gas containing Ru 3 (CO) 12 , (2,4-dimethylpentadienyl)(ethylcyclopentadienyl)ruthenium: (Ru(DMPD)(EtCp)), bis(2,4-dimethylpentadienyl)Ruthenium: (Ru(DMPD) 2 ), 4-dimethylpentadienyl(methylcyclopentadienyl)Ruthenium: (Ru(DMPD)(MeCp)), Bis(Cyclopentadienyl)Ruthenium: (Ru(C 5 H 5 ) 2 ), Cis-dicarbonylbis(5-methylhexane-2,4-dionate)ruthenium(II), and bis(ethylcyclopentadienyl)Ruthenium(II): Ru(EtCp) 2 .
9 . The method of claim 6 , wherein the removing the tungsten oxide film and the embedding the ruthenium are continuously performed without exposing the substrate to air.
10 . The method of claim 4 , wherein the removing the tungsten oxide film and the forming the tungsten film on the bottom portion of the recess are performed in a same processing chamber.
11 . The method of claim 4 , wherein the forming the tungsten film on the bottom portion of the recess is performed using an atomic layer deposition method in which no plasma is used.