Seiko Suzuki

Capacitance type accelerometer

A capacitance type accelerometer, having a fist silicon plate formed a movable electrode which is moved according to acceleration, two second silicon plates which are disposed on both sides of the first silicon plate with a certain separation distance, and thermal oxide films which are respectively disposed between the first silicon plate except the movable electrode and the two second silicon plates and stick the first silicon plate except the movable electrode and the two second silicon plates together. And further, a capacitance type accelerometer, having, a silicon plate forming a movable electrode which is moved according to acceleration, glass plates respectively mounting a conductive layer thereon which are opposite to the silicon plate with a certain separation distance and are connected to both sides of the silicon plate except the movable electrode and lead wires which are respectively connected to the conductive layers through a groove formed between the silicon plate and the glass plates.

Semiconductor capacitance-type accelerometer with PWM electrostatic servo technique

Abstract A new semiconductor capacitance-type accelerometer utilizing a pulse width modulation (PWM) electrostatic servo technique has been developed. Highly accurate detection of feeble and low frequency acceleration became possible with the PWM sensing method. The limited air gaps between the movable and fixed electrodes ensured compatibility between high sensitivity and durability, while transverse sensitivity was reduced due to the symmetric structure of the sensing part.