Plasma processing method and plasma processing apparatus
A substrate processing method includes preparing a substrate. The substrate includes a first region and a second region providing an opening on the first region. The substrate processing method further includes forming a top deposit on a top of the second region by using a first plasma generated from a first gas. The substrate processing method further includes forming a first film on a surface of the top deposit and a sidewall surface defining the opening, the first film having a thickness decreasing along a depth direction of the opening.
1 . A substrate processing method comprising:
(a) preparing a substrate including a first region and a second region formed on the first region, the second region providing an opening on the first region;
(b) forming a top deposit on a top of the second region, by using a plasma generated from a gas;
(c) forming a first film on a surface of the top deposit and a sidewall surface defining the opening, the first film having a thickness decreasing along a depth direction of the opening; and
(d) after (c), adsorbing a precursor onto the substrate and modifying the precursor on the substrate, thereby forming a second film on the substrate.
2 . The substrate processing method according to claim 1 ,
wherein the first region is a silicon-containing film and the top deposit contains carbon, boron, or a metal, or the first region is an organic film and the top deposit contains boron or a metal.
3 . The substrate processing method according to claim 2 , further comprising:
(e) after (d), etching the first region.
4 . The substrate processing method according to claim 3 , wherein in the etching the first region in (e), the top deposit is formed of a material having an etching rate lower than that of a material of the second region.
5 . The substrate processing method according to claim 2 , wherein the second film is a tungsten-containing film, a tin-containing film, an aluminum-containing film, or a hafnium-containing film.
6 . The substrate processing method according to claim 1 , wherein the sidewall surface of the opening has a width that decreases along its depth direction and is inclined with respect to a vertical direction.
7 . The substrate processing method according to claim 1 , wherein in (b), the top deposit is formed by a plasma CVD method.
8 . The substrate processing method according to claim 1 , wherein in (c), the first film is formed by an unsaturated ALD or CVD method.
9 . The substrate processing method according to claim 1 , wherein the first film is a silicon oxide film, a carbon-containing film, or a metal-containing film.
10 . The substrate processing method according to claim 1 , wherein the second region is a polycrystalline silicon film, an organic film, or a resist film.
11 . The substrate processing method according to claim 1 , wherein the first region is a silicon film, a silicon oxide film, a silicon nitride film, a stacked film including a silicon oxide film and a silicon nitride film, or an amorphous carbon film.
12 . The substrate processing method according to claim 1 , wherein the top deposit includes at least one of silicon, carbon, boron, and a metal.