Method and apparatus for polishing a substrate, and method for processing a substrate

A substrate processing method comprising:

• transporting a substrate from a loading and unloading section to a polishing unit;
• polishing an entirety of a back surface of the substrate by the polishing unit;
• cleaning the polished substrate by a cleaning unit;
• drying the cleaned substrate by a drying unit;
• and
• transporting the dried substrate to the loading and unloading section,
• wherein transporting of the substrate to the polishing unit, polishing of the entirety of the back surface of the substrate, cleaning of the polished substrate, drying of the cleaned substrate, and transporting of the dried substrate to the loading and unloading section are performed with the back surface of the substrate facing downward, and
• wherein polishing of the entirety of the back surface of the substrate by the polishing unit comprises:
• rotating the substrate by rotating a plurality of rollers about their respective own axes while the rollers contact a periphery of the substrate with the back surface of the substrate facing downward;
• and
• polishing the entirety of the back surface of the substrate by moving a polishing tool relative to the substrate while supplying a liquid onto the back surface of the substrate and while placing the polishing tool in contact with the back surface of the substrate, the polishing tool being located at a lower side of the substrate.

A method of polishing a back surface of a substrate comprising:

• holding a center-side area of the back surface of the substrate by a first substrate holder;
• polishing a circumference-side area of the back surface by causing a polishing tool to perform a circular motion or oscillate while placing the polishing tool in contact with the circumference-side area of the back surface of the substrate, the polishing tool being located at a lower side of the substrate;
• holding the circumference-side area of the back surface of the substrate by a second substrate holder;
• and
• polishing the center-side area of the back surface by causing the polishing tool to perform a circular motion or oscillate while placing the polishing tool in contact with the center-side area of the back surface of the substrate, the polishing tool being located at the lower side of the substrate.

A polishing apparatus comprising:

• a substrate holder configured to hold a substrate and rotate the substrate;
• a polishing head configured to bring a polishing tool into contact with a back surface of the substrate;
• and
• a polishing-head actuator configured to move the polishing head relative to the substrate when the substrate is held by the substrate holder,
• wherein the substrate holder comprises a plurality of rollers,
• the rollers are rotatable about their respective own axes,
• the rollers have substrate holding surfaces which can contact a periphery of the substrate, and
• the polishing head is disposed below the substrate holding surfaces, and faces upward.

A polishing apparatus comprising:

• a first substrate holder configured to hold a center-side area of a back surface of a substrate and to rotate the substrate;
• a second substrate holder configured to hold a circumference-side area of the back surface;
• a polishing head configured to polish the back surface of the substrate by bringing a polishing tool into contact with the back surface of the substrate;
• and
• a polishing-head actuator configured to move the polishing head relative to the substrate when the substrate is held by the first substrate holder or the second substrate holder, the polishing-head actuator including a polishing-head driving mechanism configured to cause the polishing head to perform a circular motion or oscillate.