Self-healing of Direct Written Conductive Inks for Curvilinear Circuits

Jeong, Chan Woo (Robin)

Self-healing of Direct Written Conductive Inks for Curvilinear Circuits

dc.contributor.advisor	Park, Simon
dc.contributor.author	Jeong, Chan Woo (Robin)
dc.contributor.committeemember	Du, Ke
dc.contributor.committeemember	Abbasi, Zahra
dc.contributor.committeemember	Komeili, Amin
dc.date	2023-06
dc.date.accessioned	2023-04-24T16:56:13Z
dc.date.available	2023-04-24T16:56:13Z
dc.date.issued	2023-04-18
dc.description.abstract	The increased electrification of vehicles in both automotive and aerospace industries has introduced new challenges in manufacturing complexities and weight management. Complex and heavy wirings are currently being utilized and conventional printed circuit board (PCB) manufacturing methods are limited in 2D geometries. Alternatively, a direct-writing approach presents weight and materials saving opportunities where planar substrates with circuits already printed are formed to a final shape. However, designing a circuit or a printed ink formula able to withstand the high strain of substrate forming is challenging. Instead, a circuit able to regain functionality after sustaining strain induced cracks presents a more versatile approach. In this study, a conductive ink with self-healing capabilities is developed. A copper-nanoparticle based ink compatible with existing lithographic methods is developed and printed on planar polymeric substrates. Intense pulsed light (IPL) is utilized to photothermally heat, reduce, and sinter copper nanoparticles within milliseconds. By utilizing light-matter energy absorption and the plasmonic effect, heat sensitive polymeric substrates are unaffected while conductive copper tracks are formed. After printing, drying, and IPL flashing, the substrate and printed tracks are subjected to cyclic bending and thermoforming. Afterwards flashing is performed once again to initiate the healing process through reflow of indium microparticles. These indium healing agents added to the ink bridges microcracks via capillary forces to recover severed electron pathways. Mechanisms of photothermal heating and sintering is simulated to better understand the underlying physical phenomena. Ultimately, a planarly written copper nanoparticle ink capable of surviving substrate deformation to produce curvilinear circuits is achieved. This direct writing method can provide drastic wiring weight reduction imparting fuel savings in the next generation of electronics in vehicles.
dc.identifier.citation	Jeong, R. (2023). Self-healing of direct written conductive inks for curvilinear circuits (Master's thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca.
dc.identifier.uri	http://hdl.handle.net/1880/116100
dc.identifier.uri	https://dx.doi.org/10.11575/PRISM/dspace/40946
dc.language.iso	en
dc.publisher.faculty	Schulich School of Engineering
dc.publisher.institution	University of Calgary
dc.rights	University of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.
dc.subject	direct written circuits
dc.subject	copper nanoparticle
dc.subject	self-healing
dc.subject	intense pulsed light
dc.subject	sintering
dc.subject.classification	Engineering--Electronics and Electrical
dc.subject.classification	Materials Science
dc.subject.classification	Metallurgy
dc.title	Self-healing of Direct Written Conductive Inks for Curvilinear Circuits
dc.type	master thesis
thesis.degree.discipline	Engineering – Mechanical & Manufacturing
thesis.degree.grantor	University of Calgary
thesis.degree.name	Master of Science (MSc)
ucalgary.thesis.accesssetbystudent	I do not require a thesis withhold – my thesis will have open access and can be viewed and downloaded publicly as soon as possible.