Polishing method, polishing apparatus, and substrate processing system
A polishing method capable of polishing a substrate, such as a wafer, with low running costs is disclosed. A polishing method includes: rotating a substrate while holding a back-side surface of the substrate with a vacuum suction stage; rotating a polishing head holding a plurality of polishing tools; and polishing a front-side surface of the substrate by pressing the plurality of polishing tools, which are rotating, against the front-side surface of the substrate. The front-side surface is a surface on which interconnect patterns are to be formed.
1. A polishing method comprising:
rotating a substrate while holding a back-side surface of the substrate with a vacuum suction stage;
rotating a polishing head holding a plurality of polishing tools; and
polishing a front-side surface of the substrate by pressing the plurality of polishing tools, which are rotating, against the front-side surface of the substrate while directing a liquid to a target area of the front-side surface, with the liquid in approximately parallel to the front-side surface of the substrate, the target area being located upstream of the polishing head with respect to a rotating direction of the substrate, the front-side surface being a surface on which interconnect patterns are to be formed.
2. The polishing method according to claim 1 , wherein pressing the plurality of polishing tools, which are rotating, against the front-side surface of the substrate comprises pressing the plurality of polishing tools, which are rotating, against the front-side surface of the substrate while oscillating the polishing head parallel to the front-side surface of the substrate.
3. The polishing method according to claim 2 , wherein oscillating the polishing head parallel to the front-side surface of the substrate comprises oscillating the polishing head between a central portion and an outer portion of the front-side surface of the substrate in directions parallel to the front-side surface of the substrate.
4. The polishing method according to claim 1 , wherein the liquid contains no abrasive grains therein.
5. The polishing method according to claim 1 , wherein pressing the plurality of polishing tools, which are rotating, against the front-side surface of the substrate comprises pressing the plurality of polishing tools, which are rotating, against the front-side surface of the substrate while advancing the plurality of the polishing tools in their longitudinal direction.
6. The polishing method according to claim 1 , wherein pressing the plurality of polishing tools, which are rotating, against the front-side surface of the substrate comprises pressing the plurality of polishing tools, which are rotating, against the front-side surface of the substrate without advancing the plurality of the polishing tools in their longitudinal direction.
7. The polishing method according to claim 1 , wherein the plurality of polishing tools are a plurality of polishing tapes each having a polishing surface formed of a polishing layer containing abrasive grains.
8. The polishing method according to claim 1 , wherein a flow velocity of the liquid is in a range of 1 m/second to 10 m/second.
9. The polishing method according to claim 1 , wherein the liquid is directed toward the at least one of the plurality of polishing tools from a liquid supply nozzle which is being swung horizontally relative to the substrate.
10. The polishing method according to claim 1 , further comprising:
detecting a state of the front-side surface of the substrate by a state detection sensor during polishing of the front-side surface of the substrate, the state of the front-side surface being at least one of a film thickness, the number of fine protrusions existing on the front-side surface, and a surface roughness.
11. The polishing method according to claim 1 , wherein the vacuum suction stage has a holding surface having substantially a same size as the substrate.
12. A polishing method comprising:
preparing a substrate having a front-side surface on which interconnect patterns are to be formed and a back-side surface on which no interconnect patterns are to be formed;
rotating the substrate while holding the back-side surface of the substrate with a vacuum suction stage;
rotating a polishing head holding a plurality of polishing tools; and
polishing the front-side surface of the substrate by pressing the plurality of polishing tools, which are rotating, against the front-side surface of the substrate while oscillating the polishing head parallel to the front-side surface of the substrate and while directing a liquid to a target area of the front-side surface, with the liquid in approximately parallel to the front-side surface of the substrate, the target area being located upstream of the polishing head with respect to a rotating direction of the substrate.
13. A polishing apparatus comprising:
a vacuum suction stage having a holding surface configured to hold a back-side surface of a substrate;
a stage motor configured to rotate the vacuum suction stage;
a polishing head;
a plurality of polishing tools attached to the polishing head;
a liquid supply nozzle configured to supply a liquid, the liquid supply nozzle being oriented toward a position upstream of the polishing head with respect to a rotating direction of the vacuum suction stage, the liquid supply nozzle having an ejection orifice disposed in a direction approximately parallel to the holding surface;
a head motor configured to rotate the polishing head and the plurality of polishing tools; and
an actuator configured to exert a downward load on the polishing head to cause the polishing head to press the plurality of polishing tools against a front-side surface of the substrate.
14. The polishing apparatus according to claim 13 , further comprising:
an oscillating mechanism configured to oscillate the polishing head parallel to the holding surface of the vacuum suction stage.
15. The polishing apparatus according to claim 13 , further comprising:
a state detection sensor configured to detect a state of the front-side surface of the substrate, the state detection sensor being arranged above the vacuum suction stage.
16. The polishing apparatus according to claim 13 , wherein the holding surface has substantially a same size as the substrate.
17. A substrate processing system for processing substrates successively, comprising:
a polishing apparatus;
a particle counter configured to count the number of fine protrusions existing on a front-side surface of a substrate that has been polished by the polishing apparatus;
an operation controller configured to receive the number of fine protrusions and change a polishing recipe for polishing a next substrate in the polishing apparatus,
wherein the polishing apparatus includes:
a vacuum suction stage having a holding surface configured to hold a back-side surface of the substrate;
a stage motor configured to rotate the vacuum suction stage;
a polishing head;
a plurality of polishing tools attached to the polishing head;
a liquid supply nozzle configured to supply a liquid, the liquid supply nozzle being oriented toward a position upstream of the polishing head with respect to a rotating direction of the vacuum suction stage, the liquid supply nozzle having an ejection orifice disposed approximately parallel to the holding surface;
a head motor configured to rotate the polishing head and the plurality of polishing tools; and
an actuator configured to exert a downward load on the polishing head to enable the polishing head to press the plurality of polishing tools against the front-side surface of the substrate.