Media Releases

New insights into how materials transfer heat could lead to improved electronics

May 16, 2013

TORONTO, ON – U of T Engi­neer­ing researchers, work­ing with col­leagues from Carnegie Mel­lon Uni­ver­si­ty, have pub­lished new insights into how mate­ri­als trans­fer heat, which could lead even­tu­al­ly to small­er, more pow­er­ful elec­tron­ic devices.

Inte­grat­ed cir­cuits and oth­er elec­tron­ic parts have been shrink­ing in size and grow­ing in com­plex­i­ty and pow­er for decades. But as cir­cuits get small­er, it becomes more dif­fi­cult to dis­si­pate waste heat. For fur­ther advances to be made in elec­tron­ics, researchers and indus­try need to find ways of track­ing heat trans­fer in prod­ucts rang­ing from smart phones to com­put­ers to solar cells.

Dan Sel­l­an and Pro­fes­sor Cristi­na Amon, of U of  T’s Mechan­i­cal and Indus­tri­al Engi­neer­ing depart­ment, inves­ti­gat­ed a new tool to mea­sure the ther­mal and vibra­tional prop­er­ties of solids. Work­ing with col­leagues from Carnegie Mel­lon Uni­ver­si­ty, they stud­ied mate­ri­als in which heat is trans­ferred by atom­ic vibra­tions in pack­ets called phonons. Their results were recent­ly pub­lished in Nature Com­mu­ni­ca­tions.

“In an anal­o­gy to light, phonons come in a spec­trum of col­ors, and we have devel­oped a new tool to mea­sure how dif­fer­ent col­or phonons con­tribute to the ther­mal con­duc­tiv­i­ty of solids,” said Jonathan Malen, an assis­tant pro­fes­sor of Mechan­i­cal Engi­neer­ing at CMU.

Accord­ing to the researchers, the new tool will give both indus­try and acad­e­mia a clear­er pic­ture of how an elec­tron­ic device’s abil­i­ty to dis­si­pate heat shrinks with its size, and how mate­ri­als can be struc­tured at the nanoscale to change their ther­mal con­duc­tiv­i­ty.

For exam­ple, in the ini­tial demon­stra­tion, the team showed that as sil­i­con micro­proces­sors con­tin­ue to shrink, their oper­at­ing tem­per­a­tures will be fur­ther chal­lenged by reduced ther­mal con­duc­tiv­i­ty.

“Our mod­el­ing work pro­vides an in-depth look at how indi­vid­ual phonons impact ther­mal con­duc­tiv­i­ty,” said Sel­l­an, who under­took his research as a PhD Can­di­date in Pro­fes­sor Amon’s lab. Cur­rent­ly an NSERC Post­doc­tor­al Fel­low at The Uni­ver­si­ty of Texas at Austin, Sel­l­an is devel­op­ing exper­i­men­tal tech­niques for ther­mal mea­sure­ments.

Pro­fes­sor Amon, who is also Dean of the Fac­ul­ty of Applied Sci­ence & Engi­neer­ing at U of T, said Sellan’s insights will allow researchers to design nanos­truc­tured ther­mo­elec­tric mate­ri­als with increased effi­cien­cy in con­vert­ing waste heat to elec­tri­cal ener­gy. This work has excit­ing impli­ca­tions for the future of nano-scale ther­mal con­duc­tiv­i­ty research.”

Found­ed in 1873, U of T Engi­neer­ing has approx­i­mate­ly 5,200 under­grad­u­ate stu­dents, 1,950 grad­u­ate stu­dents and 240 fac­ul­ty mem­bers. U of T Engi­neer­ing is at the fore of inno­va­tion in engi­neer­ing edu­ca­tion and research and ranks first in Cana­da and among the top Engi­neer­ing schools world­wide.

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For more infor­ma­tion, con­tact:

Ter­ry Laven­der
Com­mu­ni­ca­tions & Media Rela­tions Strate­gist
Fac­ul­ty of Applied Sci­ence & Engi­neer­ing, Uni­ver­si­ty of Toron­to
Tel: 416–978-4498
terry.lavender@utoronto.ca
www.engineering.utoronto.ca