Microresonator, band-pass filter, semiconductor device, and communication apparatus

1. A microresonator comprising:

a beam-type resonator element,

wherein

a beam that is an oscillating portion of said resonator element includes a high-resistance portion or an insulating portion, and

a center portion of said beam corresponding to a node of an oscillation mode has a plurality of parts, such that a center part of the plurality of parts is formed with higher resistance material than that of adjacent parts along a longitudinal direction of said beam.

2. A microresonator according to claim 1 , wherein said beam includes at least two layers, and an upper layer and a part of the bottom layer continuous thereto are formed with high-resistance or insulating material.

3. A microresonator according to claim 1 , wherein a portion of said beam corresponding to an interval between an input electrode and an output electrode is formed with high-resistance or insulating material.

4. A microresonator according to claim 1 , wherein a portion the plurality of parts comprises insulating material.

5. A microresonator according to claim 1 , wherein said beam is formed of a plurality of materials each having different resistivity.

6. A microresonator according to claim 1 , wherein said beam is formed of a plurality of regions each having different impurity concentration.

7. A band-pass filter comprising: a microresonator which includes a beam-type resonator element according to claim 1 .

8. A semiconductor device comprising: a microresonator which includes a beam-type resonator element according to claim 1 .

9. A communication apparatus that includes a filter which limits a pass band of transmission signals and/or reception signals, comprising: as said filter a filter based on a microresonator which includes a beam-type resonator element according to claim 1 .