Electrostatic chuck device
An electrostatic chuck device according to the present invention includes: an electrostatic chuck portion having a placement surface on which a plate-like sample is placed; a base portion for temperature adjustment disposed in opposition to the side of the electrostatic chuck portion on the opposite side from the placement surface; a bonding portion for bonding the electrostatic chuck portion and the base portion for temperature adjustment together; and an annular focus ring surrounding the periphery of the placement surface, in which the volume of a space surrounded by the electrostatic chuck portion, the focus ring, the bonding portion, and a dam portion of the base portion for temperature adjustment is greater than the amount of volume expansion of the bonding portion at the working temperature.
1. An electrostatic chuck device, comprising:
an electrostatic chuck portion having a placement surface on which a plate-like sample is placed and an internal electrode for electrostatic chucking;
a base portion for temperature adjustment arranged in opposition to the side of the electrostatic chuck portion on the opposite side from the placement surface;
a bonding portion that bonds the electrostatic chuck portion and the base portion for temperature adjustment; and
an annular focus ring that surrounds the periphery of the placement surface; wherein,
the base portion for temperature adjustment has a flat portion on which the electrostatic chuck portion is placed, and a dam portion surrounding the periphery of the electrostatic chuck portion,
the focus ring is arranged extending across the electrostatic chuck portion and the dam portion when viewed from overhead,
the bonding portion bonds the dam portion and the side of the electrostatic chuck portion,
the upper surface of the bonding portion between the dam portion and the electrostatic chuck portion is arranged below the upper surface of the electrostatic chuck portion and the dam portion,
a space is formed surrounded by the electrostatic chuck portion, the focus ring, the bonding portion and the dam portion, and
the volume of the space is greater than the amount of volume expansion of the bonding portion at the working temperature.
2. The electrostatic chuck device according to claim 1 , wherein the distance from the upper surface of the electrostatic chuck portion to the upper surface of the bonding portion is 0.1 mm or more.
3. The electrostatic chuck device according to claim 1 , wherein the upper surface of the electrostatic chuck portion is arranged above the upper surface of the dam portion, and the focus ring is supported by the upper surface of the peripheral edge of the electrostatic chuck portion.
4. The electrostatic chuck device according to claim 1 , wherein the bonding portion has a first region between the electrostatic chuck portion and the flat portion and a second region between the electrostatic chuck portion and the dam portion, and Young's modulus of the second region is smaller than Young's modulus of the first region.
5. The electrostatic chuck device according to claim 4 , wherein thermal conductivity of the second region is lower than thermal conductivity of the first region.
6. An electrostatic chuck device, comprising:
an electrostatic chuck portion having a placement surface on which a plate-like sample is placed and an internal electrode for electrostatic chucking;
a base portion for temperature adjustment arranged in opposition to the side of the electrostatic chuck portion on the opposite side from the placement surface; and
a bonding portion that bonds the electrostatic chuck portion and the base portion for temperature adjustment; wherein,
the base portion for temperature adjustment has a flat portion on which the electrostatic chuck portion is placed, and a dam portion surrounding the periphery of the electrostatic chuck portion,
the bonding portion is arranged extending from between the electrostatic chuck portion and the flat portion to between the electrostatic chuck portion and the dam portion, and
in the bonding portion, thermal conductivity of a first region between the electrostatic chuck portion and the flat portion is higher than thermal conductivity of a second region between the electrostatic chuck portion and the dam portion in the bonding portion.
7. The electrostatic chuck device according to claim 6 , wherein the first region of the bonding portion has a filler, while the second region of the bonding portion does not have a filler.
8. The electrostatic chuck device according to claim 6 , wherein Young's modulus of the second region of the bonding portion is smaller than Young's modulus of the first region of the bonding portion.
9. The electrostatic chuck device according to claim 6 , further having a focus ring arranged above the electrostatic chuck portion and the dam portion and provided around the placement surface along the circumferential direction of the placement surface, wherein
the upper surface of the bonding portion in the second region is arranged below the upper surface of the electrostatic chuck portion and the upper surface of the dam portion.
10. The electrostatic chuck device according to claim 9 , wherein the upper surface of the electrostatic chuck portion is arranged above the upper surface of the dam portion and the focus ring is supported by the upper surface of the peripheral edge of the electrostatic chuck portion.
11. The electrostatic chuck device according to claim 10 , wherein a space is formed surrounded by the electrostatic chuck portion, the focus ring, the bonding portion and the dam portion, and
the volume of the space is greater than the amount of volume expansion of the bonding portion at the working temperature.