This paper reports the testing and the theory of an Electro Static Micro Power Generator with silicon dioxide electret induced by highly doped potassium ions. This electret was formed on the etched sidewalls of comb-drive electrode. Oxide film on side-wall incorporated potassium ions was grown by steam from bubbling KOH solution. To charge SiO_2 film, bias-temperature (BT) treatment was applied to the device at about 200 V and 700 K. We have confirmed about 90V built-in potential. Maximum output power of approximately 50 nW is obtained at load resistance 100 MΩ. Acceleration vibration is 0.6 m/s^2 and resonance frequency is 58 Hz. We obtained close agreement between the experimental and theoretical values of the electrical characteristics.
