Characterization and Modeling of Mainstream and Alternative Conditioning and Polishing Technologies in Inter-Layer Dielectric and Copper Chemical Mechanical Planarization

Persistent Link:
http://hdl.handle.net/10150/193781
Title:
Characterization and Modeling of Mainstream and Alternative Conditioning and Polishing Technologies in Inter-Layer Dielectric and Copper Chemical Mechanical Planarization
Author:
Lee, Hyosang
Issue Date:
2008
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
This dissertation consists of four topics that focused on investigating the fundamental characteristics of chemical mechanical planarization (CMP) processes. These are alternative and conventional pad conditioning technologies, inhibitor characteristics of slurry additives, and pad stains in copper CMP.A high pressure micro jet (HPMJ) technology was used to investigate pad conditioning and evaluated as an alternative to conventional diamond disc pad conditioning in copper and inter-layer dielectric CMP. Results showed that the HPMJ pad conditioning system had the potential of removing slurry residues and polish by-products inside pad grooves and pores on the pad surface, thus leading to improved pad life and reduced wafer-level defects. In addition, a proposed conditioning scheme, namely a combination of diamond and HPMJ pad conditioning, allowed for stable polish results in terms of removal rate and coefficient of friction (COF).The theoretical and experimental investigation of conventional diamond disc pad conditioning was performed to explore the effects of conditioner design factors on removal rate and COF in copper CMP. In this study, conditioning affected pad surface topography and was also capable of modifying the removal rate of copper by changing the COF and the reaction temperature. Both theory and experimental results showed that friction and removal rate should both decrease as the conditioned surface became less abrupt.Ammonium dodecyl sulfate (ADS), an environmentally friendly surfactant, was evaluated as an alternative inhibitor to benzotriazole (BTA) in copper CMP. Results demonstrated that the inhibition efficiency of ADS was superior to that of BTA in terms of coefficient of friction (COF), removal rate and temperature. Spectral analysis of shear force showed the extent of the pre-existing stick-slip phenomena caused by the kinematics of the process and collision event between pad asperities with the wafer.The characterization of experimental and numerical formation of pad staining was investigated. Pad staining was a result of material removal and it increased with polishing pressure, wafer rotation rate and polishing time. Experimental results also indicated that pad staining had no significant effect on removal rate. The experimental and simulated pad staining images demonstrated that polish by-products were advected downstream with the slurry flow, and deposited on the pad surface.
Type:
text; Electronic Dissertation
Degree Name:
PhD
Degree Level:
doctoral
Degree Program:
Chemical Engineering; Graduate College
Degree Grantor:
University of Arizona
Advisor:
Philipossian, Ara
Committee Chair:
Philipossian, Ara

Full metadata record

DC FieldValue Language
dc.language.isoENen_US
dc.titleCharacterization and Modeling of Mainstream and Alternative Conditioning and Polishing Technologies in Inter-Layer Dielectric and Copper Chemical Mechanical Planarizationen_US
dc.creatorLee, Hyosangen_US
dc.contributor.authorLee, Hyosangen_US
dc.date.issued2008en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractThis dissertation consists of four topics that focused on investigating the fundamental characteristics of chemical mechanical planarization (CMP) processes. These are alternative and conventional pad conditioning technologies, inhibitor characteristics of slurry additives, and pad stains in copper CMP.A high pressure micro jet (HPMJ) technology was used to investigate pad conditioning and evaluated as an alternative to conventional diamond disc pad conditioning in copper and inter-layer dielectric CMP. Results showed that the HPMJ pad conditioning system had the potential of removing slurry residues and polish by-products inside pad grooves and pores on the pad surface, thus leading to improved pad life and reduced wafer-level defects. In addition, a proposed conditioning scheme, namely a combination of diamond and HPMJ pad conditioning, allowed for stable polish results in terms of removal rate and coefficient of friction (COF).The theoretical and experimental investigation of conventional diamond disc pad conditioning was performed to explore the effects of conditioner design factors on removal rate and COF in copper CMP. In this study, conditioning affected pad surface topography and was also capable of modifying the removal rate of copper by changing the COF and the reaction temperature. Both theory and experimental results showed that friction and removal rate should both decrease as the conditioned surface became less abrupt.Ammonium dodecyl sulfate (ADS), an environmentally friendly surfactant, was evaluated as an alternative inhibitor to benzotriazole (BTA) in copper CMP. Results demonstrated that the inhibition efficiency of ADS was superior to that of BTA in terms of coefficient of friction (COF), removal rate and temperature. Spectral analysis of shear force showed the extent of the pre-existing stick-slip phenomena caused by the kinematics of the process and collision event between pad asperities with the wafer.The characterization of experimental and numerical formation of pad staining was investigated. Pad staining was a result of material removal and it increased with polishing pressure, wafer rotation rate and polishing time. Experimental results also indicated that pad staining had no significant effect on removal rate. The experimental and simulated pad staining images demonstrated that polish by-products were advected downstream with the slurry flow, and deposited on the pad surface.en_US
dc.typetexten_US
dc.typeElectronic Dissertationen_US
thesis.degree.namePhDen_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineChemical Engineeringen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorPhilipossian, Araen_US
dc.contributor.chairPhilipossian, Araen_US
dc.contributor.committeememberShadman, Farhangen_US
dc.contributor.committeememberFarrell, Jamesen_US
dc.contributor.committeememberRaghavan, Srinien_US
dc.identifier.proquest2565en_US
dc.identifier.oclc659748498en_US
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