The micro power system, which is composed of photovoltaic solar cell, heat conductor, thermoelectric generator (TEG)
module and fin heat sink has been developed in our laboratory. A photovoltaic silicon solar cell of the P-N junction type
is sensitive to radiant energy of wavelength from 5,000 Å to 12,000 Å. Radiation under and within this range is
converted not only into electric energy but also into heat energy. The wavelength longer than this range is also converted
into heat energy, which degrades the conversion efficiency of the solar cell. TEG produces electrical power from
temperature difference via Seebeck effect that can be put under the solar cell to absorb the heat. The heat energy can be
converted into electrical power. It was found that when TEG surface area was 150mm×60mm, it could generate 0.24V
output voltage and 4.18mA short circuit at ambient temperature varying between 5-10°C at winter. It also could generate
1.3V output voltage and 16mA short circuit at ambient temperature varying between 30-36°C at summer. In fact we can
use a dc-dc boost up converter to enlarge the output voltage to meet the requirements of wireless sensor network nodes
or its recharging battery. It will be an alternative power source for many portable electronic types of equipment.
Lead magnesium niobate-lead titanate ((1-x) Pb (Mg<sub>1/3</sub>Nb<sub>2/3</sub>-xPbTiO<sub>3</sub>, PMNT) solid solution thin films were prepared on silicon substrates by Sol-Gel method. The well crystallized thin films were prepared on 700°C for 1 hour and micro-patterning of PMNT thin films were researched by wet etching. PMNT etch rate higher than 2.4μm/min could be obtained with well etch profile by using HF/HNO<sub>3</sub>/H<sub>2</sub>O. XRD analysis and ferroelectric property test showed that there were not the crystal lattice distortion and ferroelectric property change during PMNT etching. In the paper, the key technologies in the preparation and patterning of PMNT thin films were solved and had laid good technology foundation for the preparation of silicon-base ferroelectric thin film microfabricated devices.