Focus ring, substrate processing apparatus including the same, and semiconductor fabrication method using the same
A substrate processing apparatus includes a focus ring, the focus ring includes a central axis that extends in a first direction, a top surface having a first inner diameter, a bottom surface having a second inner diameter that is smaller than the first inner diameter, and an inner lateral surface between the top surface and the bottom surface, the inner lateral surface including a first inner lateral surface and a second inner lateral surface, where the second inner lateral surface extends downward from the first inner lateral surface and a first angle between the first inner lateral surface and a line corresponding to the first direction is different from a second angle between the second inner lateral surface and the line corresponding to the first direction.
1 . A substrate processing apparatus, comprising:
a focus ring,
wherein the focus ring comprises:
a central axis that extends in a first direction;
a top surface having a first inner diameter;
a bottom surface having a second inner diameter that is greater than the first inner diameter;
an inner lateral surface between the top surface and the bottom surface, the inner lateral surface comprising a first inner lateral surface and a second inner lateral surface; and
an outer lateral surface comprising a first outer lateral surface and a second outer lateral surface that extends downward in the first direction from a bottom of the first outer lateral surface,
wherein the second inner lateral surface extends downward from the first inner lateral surface,
wherein a first angle between the first inner lateral surface and a line corresponding to the first direction is different from a second angle between the second inner lateral surface and the line corresponding to the first direction,
wherein the first outer lateral surface is parallel to the first direction, and
wherein a third angle between the second outer lateral surface and the line corresponding to the first direction is an acute angle.
2 . The substrate processing apparatus of claim 1 , wherein the first inner lateral surface is parallel to the first direction, and
wherein the second angle between the second inner lateral surface and the line corresponding to the first direction is an acute angle.
3 . The substrate processing apparatus of claim 2 , the second angle is greater than about 0° and equal to or smaller than about 5°.
4 . The substrate processing apparatus of claim 1 , wherein the first inner lateral surface has a shape that is convex toward the central axis.
5 . The substrate processing apparatus of claim 1 , wherein the inner lateral surface of the focus ring further comprises a third inner lateral surface, and
wherein the third inner lateral surface is between the first inner lateral surface and the second inner lateral surface.
6 . The substrate processing apparatus of claim 1 , wherein a difference between the first inner diameter and the second inner diameter is in a range of about 0.01 mm to about 0.5 mm.
7 . A substrate processing apparatus, comprising:
an electrostatic chuck structure comprising a chuck that supports a substrate; and
a focus ring on a lateral surface of the chuck and having a central axis that extends in a first direction,
wherein the focus ring comprises a first outer lateral surface and a second outer lateral surface that extends downward in the first direction from a bottom of the first outer lateral surface,
wherein the first outer lateral surface is parallel to the first direction,
wherein an angle between the second outer lateral surface and a line corresponding to the first direction is an acute angle,
wherein a top surface of the focus ring has a first inner diameter,
wherein a bottom surface of the focus ring has a second inner diameter,
wherein the first inner diameter is smaller than the second inner diameter, and
wherein a diameter of the chuck is in a range of about 298.6 mm to about 300 mm.
8 . The substrate processing apparatus of claim 7 , wherein the top surface of the focus ring is at a level lower than a level of a top surface of the chuck.
9 . The substrate processing apparatus of claim 7 , wherein the focus ring comprises:
a first inner lateral surface between the top surface and the bottom surface; and
a second inner lateral surface that extends from the first inner lateral surface, and
wherein a first angle between the first inner lateral surface and the line corresponding to the first direction is different from a second angle between the second inner lateral surface and the line corresponding to the first direction.
10 . The substrate processing apparatus of claim 9 , wherein the focus ring further comprises a third inner lateral surface between the first inner lateral surface and the second inner lateral surface,
wherein at least one of the first inner lateral surface, the second inner lateral surface, and the third inner lateral surface has a shape that is convex toward the central axis.
11 . A substrate processing apparatus, comprising:
an electrostatic chuck structure;
a focus ring on the electrostatic chuck structure and having a central axis that extends in a first direction; and
an outer ring that at least partially surrounds the focus ring,
wherein an inner lateral surface of the focus ring comprises a first inner lateral surface and a second inner lateral surface,
wherein an outer lateral surface of the focus ring comprises a first outer lateral surface and a second outer lateral surface,
wherein the second inner lateral surface contacts the first inner lateral surface,
wherein the first inner lateral surface is closer to the electrostatic chuck structure than the second inner lateral surface,
wherein the second outer lateral surface extends downward in the first direction from a bottom of the first outer lateral surface, and
wherein the first outer lateral surface is closer to the outer ring than the second outer lateral surface.
12 . The substrate processing apparatus of claim 11 , wherein a first angle between the first inner lateral surface and a line corresponding to the first direction is different from a second angle between the second inner lateral surface and the line corresponding to the first direction.
13 . The substrate processing apparatus of claim 11 , wherein a top surface of the focus ring has a first inner diameter,
wherein a bottom surface of the focus ring has a second inner diameter, and
wherein the first inner diameter is smaller than the second inner diameter.
14 . The substrate processing apparatus of claim 11 , wherein the first inner lateral surface is parallel to the first direction, and
wherein the second inner lateral surface forms an acute angle with a line corresponding to the first direction.
15 . The substrate processing apparatus of claim 11 , wherein the inner lateral surface of the focus ring further comprises a third inner lateral surface, and
wherein the third inner lateral surface is between the first inner lateral surface and the second inner lateral surface.
16 . The substrate processing apparatus of claim 15 , wherein at least one of the first inner lateral surface, the second inner lateral surface, and the third inner lateral surface has a shape that is convex toward the electrostatic chuck structure.
17 . The substrate processing apparatus of claim 15 , wherein the first inner lateral surface and the second inner lateral surface are parallel to the first direction.
18 . The substrate processing apparatus of claim 11 , further comprising a ring lift pin extending in the first direction,
wherein the ring lift pin is below the focus ring.
19 . The substrate processing apparatus of claim 11 , further comprising:
a power supply connected to the electrostatic chuck structure;
a showerhead on the electrostatic chuck structure; and
a confinement ring between the electrostatic chuck structure and the showerhead.