  We investigate the structural and quantum transport properties of
isotopically enriched $^{28}$Si/$^{28}$SiO$_2$ 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 $1.75\times10^{11}$ cm$^{-2}$ and a peak mobility of
9800 cm$^2$/Vs are measured at a temperature of 1.7 K. The
$^{28}$Si/$^{28}$SiO$_2$ interface is characterized by a roughness of
$\Delta=0.4$ nm and a correlation length of $\Lambda=3.4$ nm. An upper bound
for valley splitting energy of 480 $\mu$eV is estimated at an effective
electric field of 9.5 MV/m. These results support the use of wafer-scale
$^{28}$Si/$^{28}$SiO$_2$ as a promising material platform to manufacture
industrial spin qubits.
