	US 12,377,515 B2
	Polishing apparatus and polishing method
Yuta Suzuki, Tokyo (JP); and Taro Takahashi, Tokyo (JP)
Assigned to EBARA CORPORATION, Tokyo (JP)
Filed by EBARA CORPORATION, Tokyo (JP)
Filed on Dec. 21, 2021, as Appl. No. 17/558,051.
Claims priority of application No. 2020-216919 (JP), filed on Dec. 25, 2020.
Prior Publication US 2022/0203498 A1, Jun. 30, 2022
Int. Cl. B24B 37/30 (2012.01); B24B 37/04 (2012.01)

CPC B24B 37/30 (2013.01) [B24B 37/042 (2013.01)]

13 Claims

1. A polishing apparatus for performing polishing between a polishing pad and a polishing target disposed to face the polishing pad, comprising:

a polishing table for holding the polishing pad;

a top ring for holding the polishing target;

a swing arm for holding the top ring;

an arm drive motor for causing the swing arm to swing through an arm angle range;

an arm torque detection circuitry configured to directly or indirectly detect arm torque imparted to the swing arm while the swing arm is swinging through a predetermined angle range, wherein the predetermined angle range is smaller than the arm angle range; and

an endpoint detection circuitry configured to detect a polishing endpoint indicating an end of the polishing on a basis of the arm torque detected by the arm torque detection circuitry,

wherein the arm torque detection circuitry is further configured to detect the arm torque at a plurality of angles, and

the endpoint detection circuitry is further configured at least to:

divide the arm torque detected at the plurality of angles only within the predetermined angle range for at least one cycle of swinging into an arm torque for each angle, wherein the at least one cycle of swinging comprises at least swinging from a predetermined angular position and back to the predetermined angular position;

interpolate the arm torque between temporally adjacent arm torques among the divided arm torque for each angle of the plurality of angles only within the predetermined angle range;

average the interpolated arm torque;

detect the polishing endpoint indicating the end of polishing on a basis of the average of the interpolated arm torques; and

end polishing when the polishing end point is detected.

11. A polishing method for performing polishing between a polishing pad and a polishing target disposed to face the polishing pad, comprising:

holding the polishing pad on a polishing table;

causing a swing arm to hold a top ring that holds the polishing target;

causing an arm drive motor to cause the swing arm to swing;

detecting, directly or indirectly, an arm torque imparted to the swing arm while the swing arm is swinging continuously in a predetermined angle range, wherein the predetermined angle range is smaller than an arm angle range of the swing arm;

detecting a polishing endpoint indicating an end of the polishing on a basis of the detected arm torque,

on detecting the arm torque, detecting the arm torques at a plurality of angles, and

on detecting the polishing endpoint, dividing the arm torque detected at the plurality of angles only within the predetermined angle range for at least one cycle of swinging into an arm torque for each angle, interpolating the arm torque between temporally adjacent arm torques among the divided arm torque for each angle of the plurality of angles only within the predetermined angle range, averaging the interpolated arm torques, detecting the polishing endpoint indicating the end of polishing on a basis of the average of the interpolated arm torques, and ending polishing when the polishing end point is detected, wherein the at least one cycle of swinging comprises at least swinging from a predetermined angular position and back to the predetermined angular position.