Apparatus, backing plate, backing film and method for chemical mechanical polishing
AssigneeKabushiki Kaisha Toshiba
InventorsTomoharu Watanabe, Nobuhiro Kato
Life of this patent
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Abstract
A polishing apparatus has a guide (5) to be pressed against a polishing cloth (7) when polishing an object (1). Within the guide, a ring (3) is arranged between a backing plate (4) and a backing film (2). When the guide and polishing cloth are rotated to rub with each other, force of the periphery of the object of pressing the polishing cloth drops. The ring prevents such a force drop, thereby equalizing polishing rates over a surface of the object. Also provided is a polishing method applied to the polishing apparatus.
Claims17
A polishing apparatus for polishing an object, comprising:
- a polishing cloth having a flat bottom face that is moved in a plane containing the bottom face and a top face that is in parallel with the bottom face, a part of the top face being pressed against a face of the object to be polished;
- a guide for surrounding the periphery of the object, the guide being pressed against the top face of said polishing cloth;
- and
- a backing structure for pressing an area of the object that is within a predetermined distance from said guide stronger than a remaining area of the object against said polishing cloth.
A backing plate comprising:
- a flat disk having top and bottom faces that are in parallel with each other;
- and
- a cylindrical ring having top and bottom faces that are in parallel with each other and are defined by concentric outer and inner circles, a diameter of the outer circle being equal to a diameter of said disk, a center of the top face of said ring agreeing with a center of the bottom face of said disk.
A backing film comprising:
- a flat disk film having top and bottom faces that are in parallel with each other;
- and
- a ring film having top and bottom faces that are in parallel with each other and are defined by concentric outer and inner circles, a diameter of the outer circle being equal to a diameter of said disk film, a center of the bottom face of said ring film agreeing with a center of the top face of said disk film.
A method of polishing an object, comprising steps of:
- (a) making the object come in contact with a backing structure and a polishing cloth while a guide being away from the polishing cloth by a gap;
- (b) pressing the object with the backing structure and the polishing cloth so that a peripheral area of the object is pressed stronger than a remaining area thereof, and at the same time pressing the guide against the polishing cloth;
- and
- (c) moving the polishing cloth with respect to the object.
Dependencies are inferred from the claim text.