Vibratory transducer
 A vibratory transducer comprising a vibratory beam composed of an n-type layer and having at least one end fixed. The vibratory beam is formed by selectively etching an n-type layer formed by adding impurities locally to a single silicon crystal. The vibratory transducer also comprises means for vibrating the vibratory beam and means for detecting vibration of the vibratory beam. The vibratory transducer measures pressure, temperature, density, etc, by detecting change in the resonant frequency of the vibratory beam. The vibratory beam can be finely etched irrespective of the density of the impurities therein by forming the vibratory beam in an alkaline aqueous solution while applying a negative DC or pulsed voltage to a p-type layer and a positive DC or pulsed voltage to an n-type layer. The vibrating and detecting means for the vibratory beam can be easily provided by making a diode and a transistor including the vibratory beam in the transducer. 
Yokogawa Electric Corporation
G G G H G G G G G G G H H G G
G01L G01L G01L H01L G01L G01L G01N G01L G01D G01P G01P H01L H04R G01N G01L
inventional inventional inventional inventional inventional inventional inventional inventional inventional inventional inventional additional additional additional inventional
Yasushi Tetsuya Kyoichi
Higashino Watanabe Ikeda