  Two-dimensional (2D) layered materials are ideal for micro- and
nanoelectromechanical systems (MEMS/NEMS) due to their ultimate thinness.
Platinum diselenide (PtSe$_{2}$), an exciting and unexplored 2D transition
metal dichalcogenides (TMD) material, is particularly interesting because its
scalable and low temperature growth process is compatible with silicon
technology. Here, we explore the potential of thin PtSe$_{2}$ films as
electromechanical piezoresistive sensors. All experiments have been conducted
with semimetallic PtSe$_{2}$ films grown by thermally assisted conversion of Pt
at a CMOS-compatible temperature of 400{\deg}C. We report high negative gauge
factors of up to -84.8 obtained experimentally from PtSe$_{2}$ strain gauges in
a bending cantilever beam setup. Integrated NEMS piezoresistive pressure
sensors with freestanding PMMA/PtSe$_{2}$ membranes confirm the negative gauge
factor and exhibit very high sensitivity, outperforming previously reported
values by orders of magnitude. We employ density functional theory (DFT)
calculations to understand the origin of the measured negative gauge factor.
Our results suggest PtSe$_{2}$ as a very promising candidate for future NEMS
applications, including integration into CMOS production lines.
