# US 2019/0168355 A1 · Polishing apparatus and polishing method

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 2019/0168355 A1
- Document ID: US20190168355A1
- Status: Published application
- Kind: A1
- Application number: 16/207,958
- Filed: 2018-12-03
- Published: 2019-06-06
- Earliest claimed: 2017-12-05
- Assignees: Ebara Corporation
- Applicants: Ebara Corporation
- Inventors: Yuta SUZUKI; Taro TAKAHASHI
- Web page: https://patentgrep.com/patent/US20190168355A1

## CPC

- B24B 37/105: {the workpieces or work carriers being actively moved by a drive, e.g. in a combined rotary and translatory movement}
- B24B 37/013: Devices or means for detecting lapping completion
- B24B 49/10: involving electrical means (B24B49/02, B24B49/08 take precedence)
- B24B 49/16: taking regard of the load
- H10P 52/00: Grinding, lapping or polishing of wafers, substrates or parts of devices
- B24B 27/0023: {grinding machines with a plurality of working posts}
- B24B 37/205: {provided with a window for inspecting the surface of the work being lapped}
- B24B 37/32: Retaining rings
- B24B 49/105: {using eddy currents}
- B24B 49/12: involving optical means
- B24B 53/017: Devices or means for dressing, cleaning or otherwise conditioning lapping tools
- B24B 57/02: for feeding of fluid, sprayed, pulverised, or liquefied grinding, polishing or lapping agents
- B24B: MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING (grinding of gear teeth B23F, of screw-threads B23G1/36; by electro-erosion B23H; abrasive or related blasting B24C; tools for grinding, buffing or sharpening B24D; polishing compositions C09G1/00; abrasives C09K3/14; electrolytic etching or polishing C25F3/00; grinding arrangements for use on assembled railway tracks E01B31/17); DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10

## Abstract

A polishing pad is held using a polishing table. The polishing table is driven to rotate using a first electric motor. The top ring for holding a semiconductor wafer and pressing the top ring against a polishing pad is driven to rotate by a top ring motor. The top ring is held by the swing arm. The swing arm is made to swing around a swing center on the swing arm by a swing shaft motor. A first output is generated by detecting a current value of the swing shaft motor. While polishing the semiconductor wafer by causing the semiconductor wafer to swing around the swing center on the swing arm, a change of a frictional force between the polishing pad and the semiconductor wafer is detected by increasing a change amount of the first output.

## Claims

### Claim 1

A polishing apparatus for polishing between a polishing pad and a polishable object disposed opposed to the polishing pad, the polishing apparatus comprising:
a polishing table that can hold the polishing pad;
a first electric motor that can drive to rotate the polishing table;
a holding section that can hold the polishable object and press the polishable object against the polishing pad;
a second electric motor that can drive to rotate the holding section;
a swing arm that holds the holding section;
a third electric motor that can swing the swing arm around a swing center on the swing arm;
a detection section that can detect a current value of one of the first, second and third electric motors and/or a torque command value of the one electric motor and can generate a first output, and
a change detection section that can increase a change amount of the first output while causing the polishable object to swing around the swing center on the swing arm and polishing the polishable object, and can detect a change of a frictional force between the polishing pad and the polishable object.

### Claim 2 (depends on 1)

The polishing apparatus according to claim 1, wherein the first output can be synchronized with swing motion of the swing arm.

### Claim 3 (depends on 1)

The polishing apparatus according to claim 1, wherein the first output can be synchronized with the fluctuation of arm torque added to the swing arm regarding to the swing center.

### Claim 4 (depends on 1)

The polishing apparatus according to any one of claim 1, wherein the change detection section can increase the change amount of the first output by multiplying the first output by a constant.

### Claim 5 (depends on 1)

The polishing apparatus according to any one of claim 1, wherein the change detection section averages the first output and can thereby reduce noise included in the first output.

### Claim 6 (depends on 1)

The polishing apparatus according to any one of claim 1, further comprising an end point detection section that can detect a polishing end point indicating an end of polishing based on a change of the detected frictional force.

### Claim 7 (depends on 1)

The polishing apparatus according to any one of claim 1, wherein the change detection section amplifies the first output or adds a predetermined value in accordance with the first output to the first output and can thereby increase the change amount of the first output.

### Claim 8 (depends on 1)

The polishing apparatus according to any one of claim 1, wherein the change detection section can obtain an amount of the first output subjected to smoothing.

### Claim 9

A polishing method for polishing between a polishing pad and a polishable object disposed opposed to the polishing pad, the polishing method comprising:
a step of holding the polishing pad using a polishing table;
a step of driving to rotate the polishing table using a first electric motor;
a step of driving to rotate a holding section for holding the polishable object and pressing the polishable object against the polishing pad using a second electric motor;
a step of holding the holding section using a swing arm;
a step of swinging the swing arm around a swing center on the swing arm using a third electric motor;
a step of detecting a current value of one of the first, second and third electric motors and/or a torque command value of the one electric motor and generating a first output; and
a step of increasing a change amount of the first output while swinging the polishable object around the swing center on the swing arm and polishing the polishable object, and detecting a change of a frictional force between the polishing pad and the polishable object.

### Claim 10

A computer readable recording medium that records a program for causing a computer to control a polishing apparatus that can polish a polishable object, the polishing apparatus comprising:
a first electric motor that can drive to rotate a polishing table that can hold a polishing pad;
a second electric motor that can drive to rotate a holding section that can hold the polishable object and can press the polishable object against the polishing pad;
a third electric motor that can swing a swing arm that holds the holding section around a swing center on the swing arm; and
a detection section that can detect a current value of one of the first, second and third electric motors and/or a torque command value of the one electric motor and can generate a first output, and causing the computer to function as:
change detection means that can detect a change of a frictional force between the polishing pad and the polishable object by increasing a change amount of the first output while swinging the polishable object around the swing center on the swing arm and polishing the polishable object; and
control means that can control polishing by the polishing apparatus.