Abstract: The need for flexibility and stackability has substantially grown for the future of bioelectronics, 3D integrated electronics, and bendable electronics. However, conventional wafer-based single-crystalline semiconductors cannot catch up with such trends because they are bound to the thick rigid wafers that are neither flexible nor stackable. Although polymer-based organic electronic materials are more compatible as they are mechanically complaint and less costly than inorganic counterparts, their electronic/photonic performance is substantially inferior to that of single-crystalline inorganic materials. For the past five years, my research group at MIT has focused on mitigating this performance-mechanical compliance dilemma by developing methods to obtain cheap, flexible, stackable, single-crystalline inorganic systems. In this talk, I will discuss our strategies to realize such a dream electronic system [1-5] and how these strategies unlock new ways of manufacturing advanced electronic systems [6-10]. I will highlight our remote epitaxy technique that can produce single-crystalline freestanding membranes from compound materials with their excellent semiconducting performance. In addition, I will present unprecedented flexible/stackable systems enabled by stacking of those freestanding 3D material membranes, e.g., world’s smallest vertically-stacked full color micro-LEDs [10], world’s best multiferroic devices [7], battery-less wireless e-skin [9,11], and reconfigurable hetero-integrated chips with AI accelerators [8,12].
References: [1] Nature 544, 340 (2017), [2] Nature Materials 17, 999 (2018), [3] Nature Materials 18, 550 (2019), [4] Nature Nanotechnology 15, 272-276 (2020), [5] Science 362, 665 (2018), [6] Nature Electronics, 2, 439 (2019), [7] Nature, 578, 75 (2020), [8] Nature Nanotechnology 15, 574 (2020), [9] Science Advances, 7, 27 (2021) [10] Nature (2023) in print, [11] Science 377, 859 (2022), [12] Nature Electronics, 5, 386 (2022)
Bio: Jeehwan Kim is a tenured faculty member at MIT. His research group’s focuses on material innovations for next generation computing and electronics. Kim joined MIT in September 2015. Before joining MIT, he was a Research Staff Member at IBM T.J. Watson Research Center in Yorktown Heights, NY since 2008 right after his Ph.D. He worked on next generation CMOS and energy materials/devices at IBM. Kim is a recipient of 20 IBM high value invention achievement awards. In 2012, he was appointed a “Master Inventor” of IBM in recognition of his active intellectual property generation and commercialization of his research. After joining MIT, he continuously worked in nanotechnology for advanced electronics/photonics. He has received the LAM Research foundation Award, IBM Faculty Award, DARPA Young Faculty Award, and DARPA Director’s Fellowship. He is an inventor of more than 200 issued/pending U.S. patents and an author of more than 50 articles in peer-reviewed journals. He currently serves as Associate Editor of Science Advances and AAAS. He received a B.S. from Hongik University, an M.S. from Seoul National University, and a Ph.D. from UCLA. All of his degrees are in Materials Science.