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We probe the accuracy limit of ab initio calculations of carrier mobilities in semiconductors, within the framework of the Boltzmann transport equation. By focusing on the paradigmatic case of silicon, we show that fully predictive calculations of electron and hole mobilities require many-body quasiparticle corrections to band structures and electron-phonon matrix elements, the inclusion of spin-orbit coupling, and an extremely fine sampling of inelastic scattering processes in momentum space. By considering all these factors we obtain excellent agreement with experiment, and we identify the band effective masses as the most critical parameters to achieve predictive accuracy. Our findings set a blueprint for future calculations of carrier mobilities, and pave the way to engineering transport properties in semiconductors by design.
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This content will become publicly available on March 31, 2027
Strain-tunable inter-valley scattering defines universal mobility enhancement in n- and p-type 2D TMDs
Strain fundamentally alters carrier transport in semiconductors by modifying their band structure and scattering pathways. In transition-metal dichalcogenides (TMDs), an emerging class of 2D semiconductors, we show that mobility modulation under biaxial strain is dictated by changes in inter-valley scattering rather than effective mass renormalization as in bulk silicon. Using a multiscale full-band transport framework that incorporates both intrinsic phonon, extrinsic impurity, and dielectric scattering, we find that tensile strain enhances n-type mobility through K–Q valley separation, while compressive strain improves p-type mobility via Γ–K decoupling. The tuning rates calculated from our full-band model far exceed those achieved by strain engineering in silicon. Both relaxed and strain-modulated carrier mobilities align quantitatively with experimentally verified measurements and are valid across a wide range of practical FET configurations. The enhancement remains robust across variations in temperature, carrier density, impurity level, and dielectric environment. Our results highlight the pivotal role of strain in improving the reliability and performance of 2D TMD-based electronics.
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- Award ID(s):
- 2309037
- PAR ID:
- 10683442
- Publisher / Repository:
- npj 2D materials and applications
- Date Published:
- Journal Name:
- npj 2D Materials and Applications
- ISSN:
- 2397-7132
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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