Dielectrically transduced single-ended to differential MEMS filter

A method of manufacturing a MEMS filter, comprising:

• forming an input dielectric layer and an output dielectric layer on a base;
• forming an input patterned electrode layer at least in part on the input dielectric layer;
• forming an output patterned electrode layer at least in part on the output dielectric layer;
• etching the base to define a first resonator structure and a second resonator structure coupled to the first resonator structure such that movement transduced in the first resonator structure by an input signal applied to the input patterned electrode layer causes movement in the second resonator structure which transduces an output signal in the output patterned electrode layer;
• and
• wherein:
• a) the first resonator structure and the input patterned electrode layer are coupled at least in part by the input dielectric layer;
• and
• b) the second resonator structure and the output patterned electrode layer are coupled at least in part by the output dielectric layer.

A radio frequency (RF) apparatus, comprising:

• a) an input configured to receive an input RF signal;
• b) a plurality of MEMS filters, each comprising:
• i) an input layer for receiving a single-ended signal input;
• ii) an output layer for providing a differential signal output;
• iii) a first resonator;
• and
• iv) a second resonator coupled to the first resonator such that movement transduced in the first resonator by the single-ended signal input causes movement of the second resonator which transduces the differential signal output, and wherein the first and second resonators are tuned to allow a band of frequencies to pass from the single-ended signal input to the differential signal output;
• and
• wherein the band of frequencies allowed to pass from the signal input to the signal output in each of the plurality of MEMS filters is different;
• c) switching circuitry which routes the input RF signal to a desired MEMS filter from the plurality of MEMS filters;
• and
• d) an output configured to provide the differential signal output from the desired MEMS filter.

A MEMS filter, comprising:

• a frame;
• an output resonator coupled to the frame by anchor beams;
• an input resonator coupled to the output resonator by at least one coupling beam;
• an input dielectric layer covering at least part of the input resonator;
• an output dielectric layer covering at least part of the output resonator;
• an input electrode covering at least part of the input dielectric layer and configured to receive an input signal comprising an input DC bias voltage and a single-ended RE voltage signal from a device with a first impedance, wherein the combination of the input DC bias voltage and the single-ended RE voltage signal compresses the input dielectric layer and drives a movement of the input resonator;
• a first output electrode covering at least part of the output dielectric layer;
• a second output electrode covering at least another part of the output dielectric layer;
• wherein the first and second output electrodes are configured to receive an output DC bias voltage;
• wherein movement of the input resonator tends to cause movement of the output resonator depending on the characteristics of the input signal, the input DC bias voltage, the anchor beams, the at least one coupling beam, the input dielectric layer, and the input electrode;
• and
• wherein movement of the of the output resonator creates a differential output signal at a second impedance between the first output electrode and the second output electrode depending on characteristics of the output DC bias voltage, the output dielectric layer, the first output electrode, and the second output electrode.