Polishing apparatus and polishing method

Patent metadata

Field	Value
Publication number	US-2017239784-A1
Application number	US-201715431062-A
Country	US
Kind code	A1
Filing date	Feb 13, 2017
Priority date	Feb 19, 2016
Publication date	Aug 24, 2017
Grant date	—

Abstract

A polishing apparatus and a polishing method capable of detecting whether a polishing tool has been brought into contact with a substrate, such as a wafer, and further capable of detecting a position of the polishing tool are disclosed. The polishing apparatus includes a substrate holder configured to hold a substrate, a pressing member configured to press a polishing tool against a surface of the substrate, an actuator configured to apply a pressing force to the pressing member, a motor-drive moving device configured to move the pressing member along the surface of the substrate, and a monitoring device configured to emit an alarm if a motor current supplied to the motor-drive moving device is smaller than a threshold value.

First claim

What is claimed is:

1 . A polishing apparatus comprising:
a substrate holder configured to hold a substrate; a pressing member configured to press a polishing tool against a surface of the substrate; an actuator configured to apply a pressing force to the pressing member; a motor-drive moving device configured to move the pressing member along the surface of the substrate; and a monitoring device configured to emit an alarm if a motor current supplied to the motor-drive moving device is smaller than a threshold value.

2 . The polishing apparatus according to claim 1 , wherein the monitoring device is configured to calculate an average of the motor current measured within a predetermined period of time and to emit the alarm if the average of the motor current is smaller than the threshold value.

3 . The polishing apparatus according to claim 2 , wherein the predetermined period of time is a period of time including at least a part of a period of time during which the motor-drive moving device is moving the pressing member along the surface of the wafer.

4 . The polishing apparatus according to claim 1 , further comprising:
a load measuring device disposed between the pressing member and the actuator, wherein the monitoring device is configured to emit the alarm if a load measured by the load measuring device is smaller than a set value.

5 . A polishing apparatus comprising:
a substrate holder configured to hold a substrate; a pressing member configured to press a polishing tool against a surface of the substrate; an actuator configured to apply a pressing force to the pressing member; a motor-drive moving device configured to move the pressing member along the surface of the substrate; a distance measuring device configured to measure a movement distance of the pressing member that has been moved toward the surface of the substrate by the actuator; and a monitoring device configured to emit an alarm if the movement distance is smaller than a threshold value.

6 . The polishing apparatus according to claim 5 , wherein the monitoring device is configured to emit the alarm and instruct the actuator to move the pressing member back to a retreated position and then to move the pressing member toward the surface of the substrate again, if the movement distance is smaller than the threshold value.

7 . The polishing apparatus according to claim 5 , wherein the monitoring device is configured to instruct the motor-drive moving device to move the pressing member along the surface of the substrate, if the movement distance is larger than the threshold value.

8 . The polishing apparatus according to claim 5 , further comprising:
a load measuring device disposed between the pressing member and the actuator, wherein the monitoring device is configured to emit the alarm if a load measured by the load measuring device is smaller than a set value.

9 . The polishing apparatus according to claim 5 , wherein the distance measuring device comprises a non-contact-type distance sensor.

10 . The polishing apparatus according to claim 5 , wherein the distance measuring device comprises one of a digital gage, a magnetic sensor, and an eddy current sensor.

11 . A polishing method comprising:
holding a substrate with a substrate holder; pressing a polishing tool against a surface of the substrate with a pressing member; moving the pressing member along the surface of the substrate with a motor-drive moving device; and emitting an alarm if a motor current supplied to the motor-drive moving device is smaller than a threshold value.

12 . The polishing method according to claim 11 , wherein said emitting the alarm comprises calculating an average of the motor current measured within a predetermined period of time, and emitting the alarm if the average of the motor current is smaller than the threshold value.

13 . The polishing method according to claim 12 , wherein the predetermined period of time is a period of time including at least a part of a period of time during which the motor-drive moving device is moving the pressing member along the surface of the wafer.

14 . The polishing method according to claim 11 , further comprising:
measuring a load applied to the pressing member; and emitting an alarm if the load is smaller than a set value.

15 . The polishing method according to claim 11 , wherein the surface of the substrate comprises a back surface of the wafer.

16 . A polishing method comprising:
holding a substrate with a substrate holder; moving a pressing member, which supports a polishing tool, toward a surface of the substrate with an actuator; measuring a movement distance of the pressing member that has been moved by the actuator; and emitting an alarm if the movement distance is smaller than a threshold value.

17 . The polishing method according to claim 16 , wherein said emitting the alarm comprising emitting an alarm, and moving the pressing member back to a retreated position with the actuator and then moving the pressing member toward the surface of the substrate again, if the movement distance is smaller than the threshold value.

18 . The polishing method according to claim 16 , further comprising:
moving the pressing member along the surface of the substrate with a motor-drive moving device if the movement distance is larger than the threshold value.

19 . The polishing method according to claim 16 , further comprising:
measuring a load applied from the actuator to the pressing member; and emitting an alarm if the load is smaller than a set value.

20 . The polishing method according to claim 16 , wherein the surface of the substrate comprises a back surface of the wafer.

Assignees

• Ebara Corp

Inventors

• Kamimura Kenji
• Kobayashi Kenichi

Classifications

• B24B37/11

  Lapping tools · CPC title

• B24B21/06

  involving members with limited contact area pressing the belt against the work, e.g. shoes sweeping across the whole area to be ground (B24B21/12 takes precedence) · CPC title

• B24B57/02

  for feeding of fluid, sprayed, pulverised, or liquefied grinding, polishing or lapping agents · CPC title

• B24B37/30

  for single side lapping of plane surfaces · CPC title

• B24B51/00 Primary

  Arrangements for automatic control of a series of individual steps in grinding a workpiece (if applicable to other machine tools, G05B takes precedence) · CPC title