Ultralow-dielectric-constant amorphous boron nitride
Authors: Stephan Roche
Yeongdong Lee
Tae Joo Shin
Hansol Jeon
Min-Hyun Lee
Gwangwoo Kim
Kyuwook Ihm
Seokmo Hong
Seong In Yoon
Eun-Chae Jeon
Chang-Seok Lee
Sang Won Kim
Hyeon-Jin Shin
Zonghoon Lee
Kyung Yeol Ma
Ki-Jeong Kim
Hyeon Suk Shin
Manish Chhowalla
Ju-Young Kim
Hyung-Ik Lee
Aleandro Antidormi
Journal: Nature (2020)
Discipline: Multidisciplinary
Keywords: processing speed; resistance; capacitance delay; interconnects; dielectric layers
Affiliations: Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST), Ulsan, South Korea., Inorganic Material Lab., Samsung Advanced Institute of Technology (SAIT), Suwon, South Korea., School of Materials Science and Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, South Korea., Center for Multidimensional Carbon Materials, Institute for Basic Science (IBS), Ulsan, South Korea., Department of Energy Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, South Korea., Pohang Accelerator Laboratory, Gyeongbuk, South Korea., UNIST Central Research Facilities, Ulsan, South Korea., School of Materials Science and Engineering, University of Ulsan, Ulsan, South Korea., Analytical Engineering Group, Samsung Advanced Institute of Technology (SAIT), Suwon, South Korea., Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Barcelona, Spain., Institucio Catalana de Recerca i Estudis Avancats (ICREA), Barcelona, Spain., Department of Materials Science & Metallurgy, University of Cambridge, Cambridge, UK. ., Inorganic Material Lab., Samsung Advanced Institute of Technology (SAIT), Suwon, South Korea. ., Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST), Ulsan, South Korea. ., Center for Multidimensional Carbon Materials, Institute for Basic Science (IBS), Ulsan, South Korea. ., Department of Energy Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, South Korea. ., Low-Dimensional Carbon Materials Center, Ulsan National Institute of Science and Technology (UNIST), Ulsan, South Korea. .

Abstract:  Decrease in processing speed due to increased resistance and capacitance delay is a major obstacle for the down-scaling of electronics1-3. Minimizing the dimensions of interconnects (metal wires that connect different electronic components on a chip) is crucial for the miniaturization of devices. Interconnects are isolated from each other by non-conducting (dielectric) layers. So far, research has mostly focused on decreasing the resistance of scaled interconnects because integration of dielectrics using low-temperature deposition processes compatible with complementary metal-oxide-semiconductors is technically challenging. Interconnect isolation materials must have low relative dielectric constants (κ values), serve as diffusion barriers against the migration of metal into semiconductors, and be thermally, chemically and mechanically stable. Specifically, the International Roadmap for Devices and Systems recommends4 the development of dielectrics with κ values of less than 2 by 2028. Existing low-κ materials (such as silicon oxide derivatives, organic compounds and aerogels) have κ values greater than 2 and poor thermo-mechanical properties5. Here we report three-nanometre-thick amorphous boron nitride films with ultralow κ values of 1.78 and 1.16 (close to that of air, κ = 1) at operation frequencies of 100 kilohertz and 1 megahertz, respectively. The films are mechanically and electrically robust, with a breakdown strength of 7.3 megavolts per centimetre, which exceeds requirements. Cross-sectional imaging reveals that amorphous boron nitride prevents the diffusion of cobalt atoms into silicon under very harsh conditions, in contrast to reference barriers. Our results demonstrate that amorphous boron nitride has excellent low-κ dielectric characteristics for high-performance electronics. 

Retracted: No

PubPeer comments:
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