  We report the fabrication of hexagonal-boron-nitride (hBN) encapsulated
multi-terminal WSe$_2$ Hall bars with 2D/2D low-temperature Ohmic contacts as a
platform for investigating the two-dimensional (2D) metal-insulator transition.
We demonstrate that the WSe$_2$ devices exhibit Ohmic behavior down to 0.25 K
and at low enough excitation voltages to avoid current-heating effects.
Additionally, the high-quality hBN-encapsulated WSe$_2$ devices in ideal
Hall-bar geometry enable us to accurately determine the carrier density.
Measurements of the temperature ($T$) and density ($n_s$) dependence of the
conductivity $\sigma(T,n_s)$ demonstrate scaling behavior consistent with a
metal-insulator quantum phase transition driven by electron-electron
interactions, but where disorder-induced local magnetic moments are also
present. Our findings pave the way for further studies of the fundamental
quantum mechanical properties of 2D transition metal dichalcogenides using the
same contact engineering.
