Oxidation and Removal of Thin Organic Films From A Wafer Surface: Fundamentals of Ozonated Water Application and Water Recycle.

Persistent Link:
http://hdl.handle.net/10150/191255
Title:
Oxidation and Removal of Thin Organic Films From A Wafer Surface: Fundamentals of Ozonated Water Application and Water Recycle.
Author:
DeGenova, John.
Issue Date:
2001
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:
A comprehensive Ultrapure Water (UPW) simulator program has been developed to model each unit process in UPW systems, including the entire dynamic system in real time. The program estimates the removal efficiencies for contaminants generated in semiconductor processes and in municipal water supplies. Calculations are performed using flow balance and concentration profile determinations at each unit process throughout the system. Simulator validation occurred using existing industrial facilities. Spent rinsewater (SRW) recycling in semiconductor facilities has been shown to provide significant UPW quality improvements. Contrary to many perceptions, this recycling is not a compromise to the quality, but an improvement. Benefits to the cost, reliability, and environmental improvements have also been identified. Processing risks have also been identified as the use of UPW with even minute quantities of contaminants, in particular the organic contaminants, could cause process problems. The simulator has been shown to be quite capable of predicting the impact on UPW quality due to excursions in SRW quality from semiconductor processes. Photolithography is a primary semiconductor process where organic photoresist is removed from wafers with corrosive chemistries. SRW is contaminated with both organic residues and corrosive chemicals. Ozonated UPW has recently become an alternative chemical for photoresist removal. A single-wafer tool was fabricated out of quartz designed for various processes. With direct observation of the wafer possible. Ultraviolet light experiments were also performed, directing light through the quartz, process solution, and onto the wafer. Experimental procedures were developed to study the effects of turbulence, wafer pretreatment, in-situ process treatments, and vibration on the kinetics and mechanism of photoresist removal by ozonated UPW. Data was obtained to determine which oxidation pathway was dominant; direct ozone, or indirect oxidation through radical formation. Intermediate products were determined using Fourier Transform Infrared Spectroscopy. Two distinct mechanisms were observed: film dissolution via a uniform sheeting method, and a non-uniform vapor-phase bubble mechanism where film dissolution occurred underneath the bubble. Models were developed that describe the film removal under both mechanisms. The uniform sheeting model describes typical process conditions in current tools. This model was validated and found in good agreement with experimental data.
Type:
Dissertation-Reproduction (electronic); text
Keywords:
Hydrology.; Oxidation.; Ozone -- Environmental aspects.; Water reuse.
Degree Name:
Ph. D.
Degree Level:
doctoral
Degree Program:
Chemical and Environmental Engineering; Graduate College
Degree Grantor:
University of Arizona
Committee Chair:
Shadman, Farhang

Full metadata record

DC FieldValue Language
dc.language.isoenen_US
dc.titleOxidation and Removal of Thin Organic Films From A Wafer Surface: Fundamentals of Ozonated Water Application and Water Recycle.en_US
dc.creatorDeGenova, John.en_US
dc.contributor.authorDeGenova, John.en_US
dc.date.issued2001en_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.abstractA comprehensive Ultrapure Water (UPW) simulator program has been developed to model each unit process in UPW systems, including the entire dynamic system in real time. The program estimates the removal efficiencies for contaminants generated in semiconductor processes and in municipal water supplies. Calculations are performed using flow balance and concentration profile determinations at each unit process throughout the system. Simulator validation occurred using existing industrial facilities. Spent rinsewater (SRW) recycling in semiconductor facilities has been shown to provide significant UPW quality improvements. Contrary to many perceptions, this recycling is not a compromise to the quality, but an improvement. Benefits to the cost, reliability, and environmental improvements have also been identified. Processing risks have also been identified as the use of UPW with even minute quantities of contaminants, in particular the organic contaminants, could cause process problems. The simulator has been shown to be quite capable of predicting the impact on UPW quality due to excursions in SRW quality from semiconductor processes. Photolithography is a primary semiconductor process where organic photoresist is removed from wafers with corrosive chemistries. SRW is contaminated with both organic residues and corrosive chemicals. Ozonated UPW has recently become an alternative chemical for photoresist removal. A single-wafer tool was fabricated out of quartz designed for various processes. With direct observation of the wafer possible. Ultraviolet light experiments were also performed, directing light through the quartz, process solution, and onto the wafer. Experimental procedures were developed to study the effects of turbulence, wafer pretreatment, in-situ process treatments, and vibration on the kinetics and mechanism of photoresist removal by ozonated UPW. Data was obtained to determine which oxidation pathway was dominant; direct ozone, or indirect oxidation through radical formation. Intermediate products were determined using Fourier Transform Infrared Spectroscopy. Two distinct mechanisms were observed: film dissolution via a uniform sheeting method, and a non-uniform vapor-phase bubble mechanism where film dissolution occurred underneath the bubble. Models were developed that describe the film removal under both mechanisms. The uniform sheeting model describes typical process conditions in current tools. This model was validated and found in good agreement with experimental data.en_US
dc.description.notehydrology collectionen_US
dc.typeDissertation-Reproduction (electronic)en_US
dc.typetexten_US
dc.subjectHydrology.en_US
dc.subjectOxidation.en_US
dc.subjectOzone -- Environmental aspects.en_US
dc.subjectWater reuse.en_US
thesis.degree.namePh. D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineChemical and Environmental Engineeringen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.chairShadman, Farhangen_US
dc.contributor.committeememberGuzman, Robertoen_US
dc.contributor.committeememberMuscat, Anthonyen_US
dc.contributor.committeememberRaghavan, Srinien_US
dc.identifier.oclc221343149en_US
All Items in UA Campus Repository are protected by copyright, with all rights reserved, unless otherwise indicated.