We investigate the structural and quantum transport properties of isotopically enriched 28Si/28SiO2 stacks deposited on 300 mm Si wafers in an industrial CMOS fab. Highly uniform films are obtained with an isotopic purity greater than 99.92\%. Hall-bar transistors with an equivalent oxide thickness of 17 nm are fabricated in an academic cleanroom. A critical density for conduction of 1.75×1011 cm−2 and a peak mobility of 9800 cm2/Vs are measured at a temperature of 1.7 K. The 28Si/28SiO2 interface is characterized by a roughness of Δ=0.4 nm and a correlation length of Λ=3.4 nm. An upper bound for valley splitting energy of 480 μeV is estimated at an effective electric field of 9.5 MV/m. These results support the use of wafer-scale 28Si/28SiO2 as a promising material platform to manufacture industrial spin qubits.
@article{arxiv.1810.06521,
title = {Quantum transport properties of industrial $^{28}$Si/$^{28}$SiO$_2$},
author = {D. Sabbagh and N. Thomas and J. Torres and R. Pillarisetty and P. Amin and H. C. George and K. Singh and A. Budrevich and M. Robinson and D. Merrill and L. Ross and J. Roberts and L. Lampert and L. Massa and S. Amitonov and J. Boter and G. Droulers and H. G. J. Eenink and M. van Hezel and D. Donelson and M. Veldhorst and L. M. K. Vandersypen and J. S. Clarke and G. Scappucci},
journal= {arXiv preprint arXiv:1810.06521},
year = {2019}
}