Substrate processing method and substrate processing apparatus
A method includes rotating a substrate, supplying a first processing liquid from a first nozzle to the substrate during a first period, and supplying a second processing liquid from a second nozzle to the substrate during a second period. First and second liquid columns are formed by the first and second processing liquids during at least partially overlapped period of the first and second periods, respectively. The shapes and arrangements of the first and second liquid columns satisfy that: at least one of first and second central axis lines of the first and second liquid columns is inclined with respect to a rotational axis line of the substrate, first and second cut surfaces obtained by cutting the first and second liquid columns along a horizontal plane at least partially overlap each other, and any point on the first central axis line is located on the second central axis line.
1. A method of processing a substrate, comprising:
rotating the substrate around a vertical axis in a horizontal posture;
starting a supply of a first processing liquid from a first nozzle to a front surface of the rotating substrate;
stopping the supply of the first processing liquid;
starting a supply of a second processing liquid from a second nozzle to the front surface of the rotating substrate;
stopping the supply of the second processing liquid;
arranging a liquid receiving cup around the rotating substrate;
receiving at least one of the first processing liquid and the second processing liquid scattering from the rotating substrate by the liquid receiving cup;
covering an upper opening of the liquid receiving cup with a ceiling plate; and
supplying an inert gas to a space between the ceiling plate and the rotating substrate during at least a portion of a first supply period, which is a period between starting and stopping the supply of the first processing liquid, and a second supply period, which is a period between starting and stopping the supply of the second processing liquid,
wherein the first supply period and the second supply period at least partially overlap each other, and a first liquid column is formed by the first processing liquid discharged from the first nozzle and a second liquid column is formed by the second processing liquid discharged from the second nozzle during the overlapped period, and
wherein a first central axis line and a first cut surface of the first liquid column, when the discharge of the second processing liquid from the second nozzle is assumed as being stopped during the overlapped period, and a second central axis line and a second cut surface of the second liquid column, when the discharge of the first processing liquid from the first nozzle is assumed as being stopped during the overlapped period, satisfy conditions as follows:
at least one of the first central axis line, which is a central axis line of the first liquid column, and the second central axis line, which is a central axis line of the second liquid column, is inclined with respect to a rotational axis line of the substrate;
the first cut surface and the second cut surface, obtained by cutting the first liquid column and the second liquid column along a horizontal plane including the front surface of the substrate, at least partially overlap each other as viewed in a direction of the rotational axis line; and
all points on the first central axis line are located on the second central axis line as viewed in the direction of the rotational axis line.
2. The method of claim 1 , wherein the first central axis line is inclined with respect to the vertical axis.
3. The method of claim 2 , wherein the first processing liquid and the second processing liquid are the same kind of processing liquids or different kinds of processing liquids, and the first supply period is a period before or after the second supply period.
4. The method of claim 1 , wherein the first central axis line is parallel to the vertical axis.
5. The method of claim 4 , wherein the first processing liquid and the second processing liquid are the same kind of processing liquids or different kinds of processing liquids, and the first supply period is a period before or after the second supply period.
6. The method of claim 1 , wherein the first central axis line and the second central axis line intersect with each other at an angle of 30 degrees or less.
7. The method of claim 1 , wherein a center of the first cut surface is in the second cut surface, and a center of the second cut surface is in the first cut surface.
8. The method of claim 1 , wherein a distance between a center of the first cut surface and a center of the second cut surface is 2 mm or less.
9. The method of claim 1 , wherein a vertical distance from an intersection point of the first central axis line with the second central axis line to the front surface of the substrate is 3 mm or less.
10. The method of claim 1 , wherein the first nozzle and the second nozzle are fixed to a common nozzle holder so as not to be movable relative to each other.
11. The method of claim 1 , wherein the first processing liquid and the second processing liquid are the same kind of processing liquids or different kinds of processing liquids, and the first supply period is a period before or after the second supply period.
12. The method of claim 1 , wherein the first nozzle and the second nozzle are fixed to the ceiling plate so as not to be movable relative to each other, or the first nozzle and the second nozzle are fixed to a nozzle holder so as not to be movable relative to each other, and
wherein the nozzle holder is inserted into an opening formed in a central portion of the ceiling plate.