Search

JP-7855781-B1 - holding device

JP7855781B1JP 7855781 B1JP7855781 B1JP 7855781B1JP-7855781-B1

Abstract

[Problem] To equalize the temperature distribution of the workpiece held by the holding device. [Solution] The holding device 1 includes a plate-shaped member 10 having a first surface S1 and a second surface S2 for holding a wafer W. The plate-shaped member 10 has a groove 50 that is recessed from the first surface S1 toward the second surface S2, and a gas passage 11 that penetrates the bottom 50B of the groove 50 and the second surface S2, through which a thermally conductive gas can pass. An outlet hole 112, which is the outlet for the thermally conductive gas in the gas passage 11, is formed at the bottom 50B of the groove 50. When the first surface S1 is viewed in plan view, the center position P2 of the outlet hole 112 and the center position P1 of the groove 50 are located at different positions. [Selection Diagram] Figure 3

Inventors

  • 稲吉 礼佳

Assignees

  • 日本特殊陶業株式会社

Dates

Publication Date
20260508
Application Date
20251007

Claims (7)

  1. The plate-shaped member comprises a first surface for holding the workpiece and a second surface located on the opposite side of the first surface, The first surface is composed of a flat portion extending parallel to the second surface and a sealing band protruding from the flat portion in the direction opposite to the second surface. The plate-shaped member includes, A groove that is recessed from the first surface toward the second surface, A gas passage is provided that penetrates the bottom of the groove and the second surface, allowing gas to pass through. A structure has been formed, The bottom portion of the groove is formed to be located closer to the second surface than the flat portion of the first surface. An outlet hole, which is the outlet for the gas in the gas passage, is formed at the bottom of the groove. When the first surface is viewed in a planar manner, the position of the center of the exit hole and the position of the center of the groove in the width direction are located at different positions. holding device.
  2. The holding device according to claim 1, wherein, when the first surface is viewed in a planar orientation, the width of the groove is greater than the diameter of the exit hole.
  3. The holding device according to claim 1, wherein the length of the groove depth extending from the first surface toward the second surface to the bottom is shorter than the length of the gas flow path extending from the second surface to the outlet hole.
  4. The holding device according to claim 1, wherein a porous plug formed of a porous material is disposed in part or all of the inside of the gas flow path.
  5. The holding device according to claim 4, wherein when the porous plug is arranged in a region of the gas flow path that includes the outlet hole, the position of the center of the porous plug and the position of the center of the groove in the width direction are at different positions when the first surface is viewed in a planar view.
  6. The holding device according to claim 1 or 4, wherein the outlet hole is formed by a plurality of holes.
  7. Multiple outlet holes corresponding to each of the multiple gas flow paths are formed in one of the grooves. The holding device according to claim 1, wherein, when the first surface is viewed in a planar manner, the positions of the centers of the plurality of exit holes are arranged in a different positional relationship with respect to the center position in the width direction of the groove.

Description

This disclosure relates to a holding device. An example of a wafer holding device used in semiconductor manufacturing is the electrostatic chuck. Generally, an electrostatic chuck comprises a ceramic substrate and a base member for cooling the ceramic substrate, and is configured to hold the wafer on the surface of the ceramic substrate by electrostatic attraction. The ceramic substrate and the base member are joined to each other by a bonding layer interposed between them. The ceramic substrate is cooled by heat transfer (thermal dissipation) between the base member and the ceramic substrate via the bonding layer. In this type of electrostatic chuck, during plasma processing such as plasma etching, a thermally conductive gas, such as helium gas, is supplied between the ceramic substrate and the wafer to remove heat from the wafer. Therefore, a conduit for guiding the externally supplied thermally conductive gas towards the wafer is formed inside the ceramic substrate of the electrostatic chuck, extending from the back surface of the substrate to the surface on which the wafer is placed. Patent Document 1 discloses an electrostatic chuck in which a groove is formed that recedes from the surface of a ceramic substrate toward the opposite surface, and gas holes extending from the back surface toward the front surface of the ceramic substrate are formed in the groove. Such a groove is formed to quickly diffuse the gas supplied from the gas holes into the space formed between the surface of the ceramic substrate and the wafer. In this electrostatic chuck, in a plan view, the center of the groove and the central axis of the gas outlet portion of the gas hole are located at the same position. Furthermore, Patent Document 2 discloses an electrostatic chuck comprising a recessed groove corresponding to the groove described above, and a plug placement hole that penetrates the ceramic substrate in the thickness direction and opens at the bottom surface of the recessed groove. A porous plug that allows gas flow is placed in the plug placement hole. Such a porous plug is provided to suppress dielectric breakdown during plasma processing within the linearly extending gas hole. In this electrostatic chuck, in a plan view, the center of the recessed groove and the center of the porous plug exposed at the bottom surface of the recess are located at the same position. Patent No. 7494973Patent No. 7546160 Figure 1 is an explanatory diagram schematically showing the general configuration of the holding device according to the first embodiment.Figure 2 is a schematic cross-sectional view showing the internal structure of the holding device according to the first embodiment.Figure 3 is a schematic cross-sectional view showing an enlarged view of the second circumferential groove and the area around the outlet hole of the gas flow path formed at its bottom.Figure 4 is a schematic plan view showing an enlarged view of the circular groove and the area around the outlet hole of the gas flow path formed at its bottom.Figure 5 is a schematic plan view showing an enlarged view of the second circumferential groove and the area around the outlet hole of the gas flow path formed at its bottom.Figure 6 is a schematic cross-sectional view showing an enlarged view of the second circumferential groove portion and the area around the outlet hole of the gas flow path formed at its bottom according to the second embodiment.Figure 7 is a schematic cross-sectional view showing an enlarged view of the second circumferential groove and the area around the outlet hole of the gas flow path formed at its bottom according to the third embodiment.Figure 8 is a schematic cross-sectional view showing an enlarged view of the second circumferential groove and the area around the outlet hole of the gas flow path formed at its bottom according to the fourth embodiment.Figure 9 is a schematic cross-sectional view showing an enlarged view of the second circumferential groove and the area around the outlet hole of the gas flow path formed at its bottom according to the fifth embodiment.Figure 10 is a schematic cross-sectional view showing an enlarged view of the second circumferential groove and the area around the outlet hole of the gas flow path formed at its bottom according to the sixth embodiment.Figure 11 is a schematic plan view showing an enlarged view of the circular groove portion and the area around the outlet hole of the gas flow path formed at its bottom according to the seventh embodiment.Figure 12 is a schematic cross-sectional view showing an enlarged view of the second circumferential groove and the area around the outlet hole of the gas flow path formed at its bottom according to the eighth embodiment. First, embodiments of this disclosure will be listed and described. (1) The holding device according to the present disclosure comprises a plate-shaped member having a first surface for holding a workpiece and a second surface located on the oppo