Method and apparatus for endpoint detection
AssigneeCabot Microelectronics Corporation
InventorDavid G. Mikolas
Life of this patent
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Abstract
This invention relates to methods of detecting a planarization endpoint in chemical mechanical planarization of a substrate wherein a detectable target is located at the endpoint and then detected during the CMP planarization. The invention also relates to layered substrates that contain a detectable target located between a first layer of material and a second layer of material. The invention also relates to methods of chemical mechanical planarization of a substrate.
Claims46
A method for endpoint detection in chemical mechanical planarization of a substrate having a first layer of material and a second layer of material, wherein the second layer of material has an exposed surface that is planarized by a method comprising:
- (a) placing a target at or near a location between the first layer of material and the second layer of material;
- (b) planarizing the second layer of material to remove at least a portion of material from the second layer;
- (c) detecting the target;
- and
- (d) adjusting said planarizing step in response to detecting the target.
A method of chemical mechanical planarization of a wafer, comprising:
- (a) placing the wafer in contact with a polishing substrate,
- wherein the wafer comprises a first layer of material, a second layer of material and a target placed at or near a location between the first layer of material and the second layer of material;
- (b) applying pressure against the backside of the substrate;
- (c) causing relative motion between the wafer and the polishing substrate;
- (d) depositing a polishing composition onto the polishing substrate;
- (e) planarizing the wafer by removing material from the second layer;
- and
- (f) adjusting the planarization step in response to detecting the target.
A substrate comprising a first layer of material, a second layer of material and a target placed at or near a location between the first layer of material and the second layer of material.
A method of detecting an event during chemical mechanical planarization of a substrate having a lower layer of material and an upper layer of material, comprising:
- placing a first target having a first distinguishable characteristic at or near a first event on the substrate, wherein the first target is encoded for the first event;
- placing a second target having a second distinguishable characteristic at or near a second event on the substrate, wherein the second target is encoded for the second event;
- planarizing the upper layer of material to remove at least a portion of material from the upper layer;
- observing the first or second target;
- and
- adjusting the planarization step in response to observing the first or second target.
Dependencies are inferred from the claim text.