Polishing apparatus and polishing method

Abstract

A polishing apparatus capable of accurately controlling a film thickness profile of a substrate by controlling each of a plurality of pressing actuators without having a complicated mechanism is disclosed. The polishing apparatus includes a polishing structure, a polishing head, and a head rotation mechanism configured to rotate the polishing head within a predetermined rotation angle range. The polishing head includes a plurality of pressing actuators. The polishing structure includes a polishing table or a polishing belt.

What is claimed is: 
     
         1 . A polishing apparatus, comprising:
 a polishing structure having a polishing surface, the polishing structure comprising a scrolling polishing table configured to move in translation along a circular path, or a polishing belt configured to move linearly along a traveling direction;   a polishing head configured to press a substrate against the polishing surface, the polishing head comprising a plurality of pressing actuators spread over an entire actuator holding surface of the polishing head and configured to independently press a specific portion of the substrate; and   a head rotation mechanism configured to rotate the polishing head within a predetermined rotation angle range.   
     
     
         2 . The polishing apparatus according to  claim 1 , wherein the pressing actuators comprise a plurality of airbags configured to apply a pressing force to the substrate, and
 wherein the airbags are connected to a plurality of fluid supply lines.   
     
     
         3 . The polishing apparatus according to  claim 1 , wherein the pressing actuators comprise a plurality of piezoelectric elements configured to apply a pressing force to the substrate, and
 wherein the piezoelectric elements are connected to a plurality of control lines for controlling operations of the piezoelectric elements.   
     
     
         4 . The polishing apparatus according to  claim 1 , wherein in a case in which the polishing structure is the polishing table, the polishing apparatus comprises a liquid supply nozzle configured to supply a liquid onto the polishing surface through a flow hole formed in the polishing table. 
     
     
         5 . The polishing apparatus according to  claim 1 , wherein the pressing actuators comprise:
 a plurality of airbags configured to apply a pressing force to the substrate and connected to a plurality of fluid supply lines; and   a plurality of piezoelectric elements configured to apply a pressing force to the substrate and being connected to a plurality of control lines.   
     
     
         6 . The polishing apparatus according to  claim 1 , wherein the polishing apparatus comprises a control box accommodating various devices configured to control operations of the pressing actuators, and
 wherein the control box is configured to rotate together with the polishing head.   
     
     
         7 . The polishing apparatus according to  claim 1 , wherein the head rotation mechanism is configured to rotate reciprocatingly the polishing head within a predetermined rotation angle range. 
     
     
         8 . The polishing apparatus according to  claim 1 , wherein the head rotation mechanism comprises:
 a motor;   a motor pulley connected to the motor;   a gear formed on an outer circumferential surface of the polishing head; and   a timing belt stretched between the motor pulley and the gear.   
     
     
         9 . The polishing apparatus according to  claim 1 , wherein the polishing apparatus comprises a control device configured to control an operation of each of the pressing actuators based on a film thickness profile of a surface to be polished of the substrate, and
 wherein the control device is configured to identify a specific portion of the substrate based on a comparison result between a current film thickness profile and a target film thickness profile, and determine a target pressing actuator corresponding to the specific portion of the substrate.   
     
     
         10 . A polishing method, comprising:
 operating a polishing structure comprising a scrolling polishing table configured to move in translation along a circular path, or a polishing belt configured to move linearly along a traveling direction;   operating a plurality of pressing actuators spread over an entire actuator holding surface of the polishing head and configured to independently press a specific portion of the substrate, to press the specific portion of the substrate against a polishing surface of the polishing structure; and   rotating the polishing head within a predetermined rotation angle range.   
     
     
         11 . The polishing method according to  claim 10 , wherein the polishing method comprising operating a plurality of airbags through a plurality of fluid supply lines connected to the airbags as the pressing actuators. 
     
     
         12 . The polishing method according to  claim 10 , wherein the polishing method comprising operating a plurality of piezoelectric elements through a plurality of control lines connected to the piezoelectric elements as the pressing actuators. 
     
     
         13 . The polishing method according to  claim 10 , wherein in a case in which the polishing structure is the polishing table, the polishing method comprising supplying a liquid from a liquid supply nozzle onto the polishing surface through a flow hole formed in the polishing table. 
     
     
         14 . The polishing method according to  claim 10 , wherein the polishing method comprising:
 operating a plurality of airbags through a plurality of fluid supply lines connected to the airbags as the pressing actuators; and   operating a plurality of piezoelectric elements through a plurality of control lines connected to the piezoelectric elements as the pressing actuators.   
     
     
         15 . The polishing method according to  claim 10 , wherein the polishing method comprises rotating reciprocatingly the polishing head within a predetermined rotation angle range. 
     
     
         16 . The polishing method according to  claim 10 , wherein the polishing method comprises identifying a specific portion of the substrate based on a comparison result between a current film thickness profile and a target film thickness profile, and determining a target pressing actuator corresponding to the specific portion.