Fabrication of 3D Microfluidic Devices by Thermal Bonding of Thin Poly(methyl methacrylate) Films

Handle URI:
http://hdl.handle.net/10754/237271
Title:
Fabrication of 3D Microfluidic Devices by Thermal Bonding of Thin Poly(methyl methacrylate) Films
Authors:
Perez, Paul
Abstract:
The use of thin-film techniques for the fabrication of microfluidic devices has gained attention over the last decade, particularly for three-dimensional channel structures. The reasons for this include effective use of chip volume, mechanical flexibility, dead volume reduction, enhanced design capabilities, integration of passive elements, and scalability. Several fabrication techniques have been adapted for use on thin films: laser ablation and hot embossing are popular for channel fabrication, and lamination is widely used for channel enclosure. However, none of the previous studies have been able to achieve a strong bond that is reliable under moderate positive pressures. The present work aims to develop a thin-film process that provides design versatility, speed, channel profile homogeneity, and the reliability that others fail to achieve. The three building blocks of the proposed baseline were fifty-micron poly(methyl methacrylate) thin films as substrates, channel patterning by laser ablation, and device assembly by thermal-fusion bonding. Channel fabrication was characterized and tuned to produce the desired dimensions and surface roughness. Thermal bonding was performed using an adapted mechanical testing device and optimized to produce the maximum bonding strength without significant channel deformation. Bonding multilayered devices, incorporating conduction lines, and integrating various types of membranes as passive elements demonstrated the versatility of the process. Finally, this baseline was used to fabricate a droplet generator and a DNA detection chip based on micro-bead agglomeration. It was found that a combination of low laser power and scanning speed produced channel surfaces with better uniformity than those obtained with higher values. In addition, the implemented bonding technique provided the process with the most reliable bond strength reported, so far, for thin-film microfluidics. Overall, the present work proved to be versatile, reliable, and fast, making it a good candidate to reproduce several on-chip functions. Future work includes implementing thick-substrate bonding techniques to further improve the process and decrease energy requirements.
Advisors:
Foulds, Ian G.
Committee Member:
Hussain, Muhammad Mustafa ( 0000-0003-3279-0441 ) ; Kosel, Jürgen ( 0000-0002-8998-8275 )
KAUST Department:
Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division
Program:
Electrical Engineering
Issue Date:
Jul-2012
Type:
Thesis
Appears in Collections:
Theses; Electrical Engineering Program; Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division

Full metadata record

DC FieldValue Language
dc.contributor.advisorFoulds, Ian G.en
dc.contributor.authorPerez, Paulen
dc.date.accessioned2012-08-05T07:11:54Z-
dc.date.available2012-08-05T07:11:54Z-
dc.date.issued2012-07en
dc.identifier.urihttp://hdl.handle.net/10754/237271en
dc.description.abstractThe use of thin-film techniques for the fabrication of microfluidic devices has gained attention over the last decade, particularly for three-dimensional channel structures. The reasons for this include effective use of chip volume, mechanical flexibility, dead volume reduction, enhanced design capabilities, integration of passive elements, and scalability. Several fabrication techniques have been adapted for use on thin films: laser ablation and hot embossing are popular for channel fabrication, and lamination is widely used for channel enclosure. However, none of the previous studies have been able to achieve a strong bond that is reliable under moderate positive pressures. The present work aims to develop a thin-film process that provides design versatility, speed, channel profile homogeneity, and the reliability that others fail to achieve. The three building blocks of the proposed baseline were fifty-micron poly(methyl methacrylate) thin films as substrates, channel patterning by laser ablation, and device assembly by thermal-fusion bonding. Channel fabrication was characterized and tuned to produce the desired dimensions and surface roughness. Thermal bonding was performed using an adapted mechanical testing device and optimized to produce the maximum bonding strength without significant channel deformation. Bonding multilayered devices, incorporating conduction lines, and integrating various types of membranes as passive elements demonstrated the versatility of the process. Finally, this baseline was used to fabricate a droplet generator and a DNA detection chip based on micro-bead agglomeration. It was found that a combination of low laser power and scanning speed produced channel surfaces with better uniformity than those obtained with higher values. In addition, the implemented bonding technique provided the process with the most reliable bond strength reported, so far, for thin-film microfluidics. Overall, the present work proved to be versatile, reliable, and fast, making it a good candidate to reproduce several on-chip functions. Future work includes implementing thick-substrate bonding techniques to further improve the process and decrease energy requirements.en
dc.language.isoenen
dc.subjectFilmen
dc.subjectFoilen
dc.subjectThermal bondingen
dc.subjectLaser ablationen
dc.subjectMicrofluidicen
dc.subjectPMMAen
dc.titleFabrication of 3D Microfluidic Devices by Thermal Bonding of Thin Poly(methyl methacrylate) Filmsen
dc.typeThesisen
dc.contributor.departmentComputer, Electrical and Mathematical Sciences and Engineering (CEMSE) Divisionen
thesis.degree.grantorKing Abdullah University of Science and Technologyen_GB
dc.contributor.committeememberHussain, Muhammad Mustafaen
dc.contributor.committeememberKosel, Jürgenen
thesis.degree.disciplineElectrical Engineeringen
thesis.degree.nameMaster of Scienceen
dc.person.id113263en
All Items in KAUST are protected by copyright, with all rights reserved, unless otherwise indicated.