Pad conditioner, pad conditioning method, and polishing apparatus

A pad preparation apparatus for conditioning a surface of a polishing pad made of foamed polyurethane which is used in a polishing apparatus for polishing works to optimize the surface as an initial state for polishing, comprising:

• a rotating table which holds and rotates the polishing pad;
• and
• a pad conditioner having a bunch of wires constituting bending or deflecting or elastic members having a sufficient flexible length to enable tip ends of the wires to contact the polishing pad at a constant pressure;
• and a supporting section to support a base end of the wires, and
• wherein said supporting section comprises a circular plate from which the bunch of wires extend in the manner of a brush, a first supporting body for fixing the base ends of the wires thereto, and a second supporting body which has a plurality of holes through which the wires pass and which is mounted to the first supporting body in a manner enabling it to move toward and away from the first supporting body for limiting the position of the wires in a plane parallel to the polishing pad thereby adjusting the effective flexible length of the wires, and
• wherein said supporting section is rotatable on the polishing pad,
• wherein the pad preparation apparatus is configured to roughen the surface of the polishing pad by rotating the pad conditioner on the polishing pad and the pad conditioner being in contact to each other, and by scraping the surface of the polishing pad.

A pad conditioning method by a pad conditioning apparatus having a table, a polishing pad which is fixed on the table and made from polyurethane material and a pad conditioner which roughens a surface of the polishing pad, wherein

• the pad conditioner includes:
• a bunch of wires constituting a plurality of elastic members which have tip ends continuously contact the surface of the polishing pad to scrape and roughen the surface of the polishing pad and have such a flexible length that enables the tip ends to contact the polishing pad at a substantially constant pressure despite variations in height of the pad;
• and
• a supporting section which supports base ends of the plurality of elastic members and is fixedly supported so as to face the table in substantially parallel relation with each other, the supporting section being circular and the elastic members being attached in the manner of a brush, the supporting section includes a first supporting body for fixing the base ends of the wires thereto, and a second supporting body which has a plurality of holes through which the wires pass and which is mounted to the first supporting body in a manner enabling it to move toward and away from the first supporting body for limiting the position of the wires in a plane parallel to the polishing pad thereby adjusting the effective flexible length of the wires, and
• the method comprising the steps of:
• rotating the supporting section of the pad conditioner relative to the table;
• bringing each of the tip ends of the wires independently into contact with the polishing pad;
• pressing the tip ends against the surface of the polishing pad at a predetermined pad conditioning pressure by elastic deformation of the wires, and
• scraping and roughening the surface of the polishing pad to evenly dress the surface of the polishing pad by the pressed wires.