| 摘要 |
PURPOSE:To contrive the stabilization of operational characteritics of the elastic surface wave element by arranging depletion layer controlling means partly on the boundary surface between a semiconductor and a piezoelectric unit and avoiding the application of DC voltage to the piezoelectric unit. CONSTITUTION:A laminate is formed of the semiconductor S and the piezoelectric unit A. Depletion layer controlling means D, D,... are formed in the boundary 12 between the semiconductor S and the piezoelectric unit A. The depletion layer controlling means D, D,... are formed in a comblike shape, are commonly connected at respective one ends, are connected through a choke coil CH for stopping high frequency current from the connecting end 13 to a variable DC power supply E for applying DC bias voltage, and are connected through a capacitor C for stopping the DC current to a high frequency power supply P for supplying a pumping current. |
