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Negative Bias Temperature Instability (NBTI) is one of the main ageing processes in MOSFET devices, and it is related among others to H diffusion within the SiO2 dielectric layer of the device. In this work we use molecular simulations to study the underlying mechanism that governs the diffusion of H within SiO2, and suggest how to modify the material to decrease it. The computed diffusion activation energies are in excellent agreement with existing experimental data, and the analysis of the diffusion paths reveals a H hopping mechanism governed by the same orientational constraints as proton exchange in bulk water. Based on this mechanism, we test a hypothetical NBTI ageing retarding modification based on a mechanical deformation of the SiO2 dielectric. Stretching of the material induces a rearrangement of the silicate units, increasing the O–O distance, and consequently the activation energy required for H diffusion. Hence, stretching of the semiconductor during the MOSFET manufacturing process could reduce significantly the NBTI-driven ageing of the devices. [ABSTRACT FROM AUTHOR]

Computational methods, or computer-aided material design (CAMD), used for the analysis and design of materials have a relatively long history. However, the applicability of CAMD has been limited by the scales of computational resources generally available in the past. The surge in computational power seen in recent years is enabling the applicability of CAMD to unprecedented levels. Here, we focus on the CAMD for materials critical for the continued advancement of the complementary metal oxide semiconductor (CMOS) semiconductor technology. In particular, we apply CAMD to the engineering of high-permittivity dielectric materials. We developed a Reax forcefield that includes Si, O, Zr, and H. We used this forcefield in a series of simulations to compute the static dielectric constant of silica glasses for low Zr concentration using a classical molecular dynamics approach. Our results are compared against experimental values. Not only does our work reveal numerical estimations on ZrO 2 -doped silica dielectrics, it also provides a foundation and demonstration of how CAMD can enable the engineering of materials of critical importance for advanced CMOS technology nodes., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)