This paper presents a detailed characterization of silicon germanium oxide (Si<sub>x</sub>Ge<sub>y</sub>O<sub>1-x-y</sub>) thin films with an Oxygen
concentration below 10%. The results demonstrated that a high TCR and a low corresponding resistivity can be achieved
using various compositions, for example, Si<sub>0.054</sub>Ge<sub>0.877</sub>O<sub>0.069</sub> film has achieved a TCR and a resistivity of -3.516/K, and
629 Ω-cm, respectively. The lowest measured resistivity and the corresponding TCR were 119.6 Ω-cm and -2.202 %/K
respectively, using Si<sub>0.136</sub>Ge<sub>0.838</sub>O<sub>0.026</sub> for film deposited at room temperature, whereas the highest achieved TCR and the
corresponding resistivity at room temperature were -5.017 %/K, and 39.1×103 Ω-cm, respectively, using
Si<sub>0.167</sub>Ge<sub>0.762</sub>O<sub>0.071</sub> for films deposited at room temperature. The calculated activation energy (E<sub>a</sub>) from the slope of
Arrhenius plots were varied between 0.1232 eV to 0.3788 eV. The X-ray diffraction study demonstrated that the films
are amorphous but did not show any dependence on varying silicon at fixed oxygen concentration. The noise study
demonstrated that these films exhibit relatively high 1/f.
We have designed, modeled, fabricated and tested novel MEMS variable capacitors with two air cavities (two capacitors) for electrostatic power harvesting utilizing mechanical vibration in environment. The device is unique in the use of an innovative two-cavity design and electroplated nickel as the main structural material, which allows using both up and down directions to generate energy. The prototype of two-cavity MEMS variable capacitors have been successfully fabricated using surface micromachining. The initial testing for investigating electrical dynamic behaviors and power generation from the fabricated devices was implemented.