  There is a substantial interest in the heterostructures of semiconducting
transition metal dichalcogenides (TMDCs) amongst each other or with arbitrary
materials, through which the control of the chemical, structural, electronic,
spintronic, and optical properties can lead to a change in device paradigms. A
critical need is to understand the interface between TMDCs and insulating
substrates, for example high-$\kappa$ dielectrics, which can strongly impact
the electronic properties such as the optical gap. Here we show that the
chemical and electronic properties of the single-layer (SL) TMDC, WS$_2$, can
be transferred onto high-$\kappa$ transition metal oxide substrates TiO$_2$ and
SrTiO$_3$. The resulting samples are much more suitable for measuring their
electronic and chemical structures with angle-resolved photoemission than their
native-grown SiO$_2$ substrates. We probe the WS$_2$ on the micron scale across
100-micron flakes, and find that the occupied electronic structure is exactly
as predicted for freestanding SL WS$_2$ with a strong spin-orbit splitting of
420~meV and a direct band gap at the valence band maximum. Our results suggest
that TMDCs can be combined with arbitrary multi-functional oxides, which may
introduce alternative means of controlling the optoelectronic properties of
such materials.
