Speedfam-ipec Corporation

Novellus Systems Incorporated

Speedfam Corporation

Thomas Laursen

Malcolm Grief

Justin M Quarantello

Krishna P Murella

Paul L Holzapfel

Paul Franzen

Mark A Meloni

Robert A Eaton

Karl Kasprzyk

Guangying Zhang

Matthew Weldon

Sanjay Basak

Daniel R Trojan

Steven Reynolds

Thomas Stotts

Rob Stoya

Mamoru Yamayoshi

A method and apparatus for 'through-the-pad' delivery of slurry polishing agents directly to the land areas of a polishing pad is disclosed. The present invention further provides for improved control of the chemical composition of the slurry to address loss of chemical reactivity of the slurry during the polishing cycle. Additionally, various groove modifications to the polishing surface of the pad are also disclosed for improved slurry retention over substantially the entire surface of the polishing pad and reduction of the slow band effect. The present invention thus provides for a higher degree of planarization and uniformity of material removed from the surface of a processed workpiece in order to eliminate, or otherwise reduce, small-scale roughness and large-scale topographic differentials as well as to reduce the Cost-of-Ownership associated with slurry costs.

Method and apparatus for controlled slurry distribution

Methods are provided for chemical mechanical planarization of a layer and for determining the endpoint of a CMP operation. In accordance with one embodiment the method for determining an endpoint comprises making a plurality of eddy current thickness measurement of the layer being planarized, each of the plurality of measurements spaced apart by a predetermined length of time. A difference is calculated between sequential ones of the plurality of eddy current measurements, and a predetermined minimum threshold for the difference is set. The endpoint is defined as a calculated difference less than the predetermined minimum threshold.

Methods for chemical mechanical planarization and for detecting endpoint of a CMP operation

Method and apparatus for controlling slurry distribution

Methods are provided for monitoring a CMP process. An exemplary method comprises generating a plurality of thickness measurements of a metal layer using an in-situ eddy current measuring system. The thickness measurements are analyzed to derive a plurality of work piece metrics and the work piece metrics are assessed to determine if a predetermined number is within a predetermined specification. A signal is generated if the predetermined number of the work piece metrics is outside the predetermined specification.

Methods for monitoring a chemical mechanical planarization process of a metal layer using an in-situ eddy current measuring system

Methods are provided for controlling adjustable pressure zones of a CMP carrier. A method comprises determining a first thickness of a layer on a wafer underlying a first zone of the carrier. A first portion of the layer underlying the first zone is removed. The first zone is configured to exert a first pressure against the second surface of the wafer. A second thickness of the layer underlying the first zone is determined and a target thickness corresponding to a predetermined thickness profile is selected. A second pressure for the first zone is calculated using the first thickness, the second thickness, the first pressure, and the target thickness. The pressure exerted by the first zone against the second surface of the wafer is adjusted to the second pressure and the steps are repeated for a second zone.

Methods for controlling the pressures of adjustable pressure zones of a work piece carrier during chemical mechanical planarization

The invention is a method and apparatus for planarizing a wafer. Discrete measurements are taken across the surface of the wafer at a desired spatial density. The measurements may be generated using a flash lamp to reflect a light signal off the surface of the wafer with a spectrometer analyzing the reflected light. A plurality of probes may be used at different locations to shorten the time necessary for taking measurements across the full front surface of the wafer and for allowing a plurality of areas to be sampled substantially simultaneously. A control system receives the measurements and their corresponding locations. The control system is then able to analyze the data looking for areas or bands on the front surface of the wafer that need an increase or decrease in material removal rate. The control system is then able to adjust one or more planarization parameters to improve the process for the current wafer or for future wafers.

Multiprobe detection system for chemical-mechanical planarization tool

The invention improves a polishing process for a wafer retained in a multizone carrier in a chemical mechanical polishing tool. A light signal is communicated to the front surface of the wafer and the reflected light signal is captured by a metrology instrument. The metrology instrument communicates the intensity of the reflected light to a control system. The location or radial position corresponding to the reflected light signal from the front surface of the wafer may be determined by the control system. From the intensity measurements and corresponding locations, the control system is able to determine an approximate topography of the wafer. The control system may alter the pressure within one or more zones within the multizone carrier to improve the polishing process. The control system may also alter the initial pressures within the multizone carrier for future wafers based on the polishing results from the present wafer.

Multizone carrier with process monitoring system for chemical-mechanical planarization tool

A system and method for determining endpoint detection in semiconductor wafer planarization is provided. The system and method provide a flexible solution that can compensate for baseline variability induced errors that may otherwise occur in endpoint detection. The system uses an endpoint detection signal that monitors the optical characteristics of the wafer being planarized. The system and method continue to monitor the detection signal during planarization until it meets endpoint criterion that indicates endpoint completion. When the endpoint criterion is reached, a new snapshot is taken from a previous time period and a new baseline is calculated. The endpoint detection signal is then recalculated based upon the new baseline and the recalculated detection signal is again compared to the endpoint criterion. If the recalculated endpoint detection signal again substantially meets the endpoint criterion then the detection of endpoint is confirmed. If the recalculated detection signal no longer meets the endpoint criterion, the planarization process continues with the new baseline used as the basis for endpoint detection.

Flexible snapshot in endpoint detection

The present invention includes a platen having a plurality of concentric fluid-tight plenums for receiving fluids. One or more fluid delivery systems may be used to control the flow rate and composition of fluids communicated to the plenums. The top surface of the platen may have holes for allowing the fluids, once inside the plenums, to travel to the top surface of a polishing pad. By controlling the flow rate and composition of fluids, the material removal rate on the front surface of the wafer may also be controlled. The polishing pad is preferably orbited during the planarization process. A metrology instrument may be used for measuring the front surface of the wafer. Data regarding the measurements may be used by a computer to determine if different flow rates and/or composition of fluids should be used to compensate for nonuniform polishing of the wafer.

Multizone slurry delivery for chemical mechanical polishing tool

A method of improving planarity of semiconductor wafer surfaces containing damascene and dual-damascene circuitry using chemical-mechanical polishing techniques. The method includes using a first polishing step to substantially remove excess surface metal up to a detected end point. After rinsing, a second step of chemical-mechanical polishing is applied, using a second slurry that has a higher selectivity for dielectric than metal, preferably from 1.8 to 4 or more times greater. The second step of polishing, in accordance with the invention, has been found to substantially eliminate dishing and improve planarity.

Two-step chemical-mechanical planarization for damascene structures on semiconductor wafers

The invention provides a method of fabricating semiconductor chips that includes modifying physical properties of selected deposit fill layers over patterns having up-features and down-features, with fill to be retained in down-features. The modification enhances chemical mechanical polishing rates, or other polishing, of the modified fill layers to reduce dishing of fill material and achieves this without substantially affecting the electrical properties of the final semiconductor chip product.

Modification to fill layers for inlaying semiconductor patterns

A method of conditioning pads used in the polishing of semiconductor wafers containing copper circuitry. The method includes applying a treatment solution that contains a reactant for particulate copper-containing debris on the pad resulting from the copper circuitry. Preferably, the reactant is a carboxylic acid present in a concentration of from about 0.1 to about 10 weight percent in a solution. The pH of the solution may be adjusted to the range from about 1 to about 6 with a compatible base.

Pad conditioning for copper-based semiconductor wafers

A method of reducing dishing and erosion of surfaces of inlaid material on semiconductor wafers. The method includes forming a sacrificial deposit or layer over at least down features of the patterned surface of the fill layer, that has a lower rate of removal during chemical-mechanical polishing than the fill layer. Elevated caps of sacrificial deposit are formed over inlaid fill material prior to pattern clearing. In CMP pattern clearing, the caps are removed and polishing proceeds at a faster rate on the slightly elevated inlaid fill upper surfaces until they are coplanar with surrounding patterned substrate. Chemical-mechanical polishing can be carried out in a single step, or in multiple steps, to produce the desired result.

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Phoenix, AZ, United States of America

Thomas Laursen