| 摘要 |
PURPOSE:To widely change the variable frequency range and to increase the selectivity Q, by providing a reflection electrode and a member giving mechanical reflection close to a surface acoustic wave transducer. CONSTITUTION:An insulation film is formed on a semiconductor substrate and signal input and output transducers 1, 2 are formed on a piezoelecrtic element attached with a piezoelectric film 5 on the insulation film, and a mechanical rugged member 20 having the mechanical reflection on one side is arranged near the transducers 1 and 2 and a pump electrode 4 is formed on the other side. A pump voltage in frequency 2f, double the selecting desired frequency (f) is applied to the pump electrode 4. When an input electric signal is applied to the input transducer 1, the signal is converted into a surface acoustic wave signal and propagated, and when the component in frequency (f) is propagated in the pump electrode 4, the component is amplified with parametric mutual operation and reflected at the same time, and further converted into the electric signal with the output transducer 2 again. |
