  This article presents a comprehensive study and design methodology of
co-integrated oscillators for nano mass sensing application based on resonant
Nano-Electro-Mechanical-System (NEMS). In particular, it reports the capacitive
with the piezoresistive transduction schemes in terms of the overall sensor
performance. The developed model is clearly in accordance with the general
experimental observations obtained for NEMS-based mass detection. The
piezoresistive devices are much sensitive (up to 10 zg/?Hz) than capacitive
ones (close to 100 zg/?Hz) since they can work at higher frequency. Moreover,
the high doped silicon piezoresistive gauge, which is of a great interest for
very large scale integration displays similar theoretical resolution than the
metallic gauge already used experimentally.
