  Bulk 1T$^\prime$-MoTe$_2$ shows a structural phase transition from
1T$^\prime$ to Weyl semimetallic (WSM) $ T_{d} $ phase at $\sim$ 240 K. This
phase transition and transport properties in the two phases have not been
investigated on ultra-thin crystals. Here we report electrical transport, $1/f$
noise and Raman studies in ultra-thin 1T$^\prime$-MoTe$_2$ ($\sim$ 5 to 16 nm
thick) field-effect transistors (FETs) devices as a function of temperature.
The electrical resistivities for thickness 16 nm and 11 nm show maxima at
temperatures 208 K and 178 K, respectively, making a transition from
semiconducting to semi-metallic phase, hitherto not observed in bulk samples.
Raman frequencies and linewidths for 11nm thick crystal show change around 178
K, attributed to additional contribution to the phonon self-energy due to
enhanced electron-phonon interaction in the WSM phase. Further, the resistivity
at low-temperature shows an upturn below 20 K along with the maximum in the
power spectral density of the low frequency $1/f$ noise. The latter rules out
the metal-insulator transition (MIT) being responsible for the upturn of
resistivity below 20 K. The low temperature resistivity follows $\rho \propto
1/T$, changing to $\rho \propto T$ with increasing temperature supports
electron-electron interaction physics at electron-hole symmetric Weyl nodes
below 20 K. These observations will pave the way to unravel the properties of
WSM state in layered ultra-thin van der Waals materials.
