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arXiv · 1706.10178

Two-Dimensional h-BN and MoS2 as Diffusion Barriers for Ultra-Scaled Copper Interconnects

Chun-Li Lo·Massimo Catalano·Kirby K. H. Smithe·Luhua Wang·Shengjiao Zhang·Eric Pop·Moon J. Kim·Zhihong Chen
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Abstract

Copper interconnects in modern integrated circuits require ultra-thin barriers to prevent intermixing of Cu with surrounding dielectric materials. Conventional barriers rely on metals like TaN, however their finite thickness reduces the cross-sectional area and significantly increases the resistivity of nanoscale interconnects. In this study, a new class of two-dimensional (2D) Cu diffusion barriers, hexagonal boron nitride (h-BN) and molybdenum disulfide (MoS2), is demonstrated for the first time. Using time-dependent dielectric breakdown measurements and scanning transmission electron microscopy coupled with energy dispersive X-ray spectroscopy and electron energy loss spectroscopy, these 2D materials are shown to be promising barrier solutions for ultra-scaled interconnect technology. The predicted lifetime of devices with directly deposited 2D barriers can achieve three orders of magnitude improvement compared to control devices without barriers.

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Chun-Li Lo, Massimo Catalano, Kirby K. H. Smithe, Luhua Wang, Shengjiao Zhang, Eric Pop, Moon J. Kim, Zhihong Chen. 2017-06-30. Two-Dimensional h-BN and MoS2 as Diffusion Barriers for Ultra-Scaled Copper Interconnects. https://arxiv.org/abs/1706.10178

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