Polishing pad with flow modifying groove network
AssigneeRohm and Haas Electronic Materials CMP Holdings, Inc.
InventorRavichandra V. Palaparthi
Life of this patent
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Abstract
A polishing pad (20) for polishing a wafer (32) or other article, the pad having a groove network (60) configured to vary the residence time across the wafer track of the reaction products formed by the interaction of reactants in the polishing medium (46) with structure on the wafer. The groove network has a first portion (72) that may extend substantially radially outward and a second portion (74) that is configured to vary the speed of the radially outward flow of the polishing medium.
Claims10
A polishing pad for polishing an article, the polishing pad comprising:
- a. a polishing portion having a rotational axis and a plurality of grooves, each groove including:
- i. a first portion;
- and
- ii. a second portion in communication with the first portion at a transition location;
- and
- b. wherein the transition location of at least a first one of the plurality of grooves is spaced a first radial distance from the rotational axis and the transition location of at least a second one of the plurality of grooves is spaced a second radial distance from the rotational axis, the first radial distance being different than the second radial distance.
A method of polishing an article using a polishing pad having a rotational axis and a polishing medium, the method comprising the steps of:
- a. providing a pad having a plurality of grooves that extends outward from the rotational axis;
- b. engaging the pad with a surface of the article;
- c. effecting relative rotation between the pad and the article so that a track of the pad contacts the article;
- and
- d. causing the polishing medium to flow between the track of the pad and the surface of the article within the plurality of grooves with different residence times in at least two of the plurality of grooves.
A polishing pad for polishing an article with the use of a polishing medium, the pad comprising:
- a. a polishing portion having rotational axis and a plurality of grooves, each groove including:
- i. a first portion;
- and
- ii. a second portion in communication with the first portion at a transition location, the second portion having a length and a cross-sectional configuration that varies along at least a portion of the length so as to increase residence time of polishing medium located in the second portion;
- and
- b. wherein the transition location of each of the plurality of grooves is spaced one of a plurality of different radial distances from the rotational axis.
Dependencies are inferred from the claim text.