Nonuniform corrugated diaphragm for mems tuners and actuators

Abstract

A cavity resonator tuning diaphragm comprising a plurality of inner corrugations, the plurality of inner corrugations having a first depth. An outer corrugation located between the plurality of inner corrugations and a perimeter of the diaphragm is also included, the outer corrugation having a second depth greater than the first depth. The addition of the outer deep corrugation provides increased thermal stability and reduced required actuation voltage.

1 . A MEMS RF cavity resonator tuning diaphragm, comprising:
 an RF tuning diaphragm surface having a plurality of inner corrugations, the plurality of inner corrugations having a first depth, wherein the diaphragm has a radius less than 5000 μm;   an outer corrugation located between the plurality of inner corrugations and a perimeter of the diaphragm, the outer corrugation having a second depth greater than the first depth.   
     
     
         2 . The diaphragm of  claim 1 , wherein the diaphragm is circular and wherein the inner corrugations and outer corrugation comprise concentric circles, the inner corrugations having lateral radii smaller than a lateral radius of the outer corrugation. 
     
     
         3 . The MEMS RF cavity resonator tuning diaphragm of  claim 1 , further comprising a plurality of holes formed in the diaphragm, the holes forming concentric rings in the diaphragm. 
     
     
         4 . The MEMS RF cavity resonator tuning diaphragm of  claim 1 , wherein the diaphragm comprises gold. 
     
     
         5 . A MEMS RF resonator tuner, comprising:
 a diaphragm having a plurality of inner corrugations and an outer corrugation, the outer corrugation located between the plurality of inner corrugations and a perimeter of the diaphragm, the inner corrugations having a first depth smaller than a second depth of the outer corrugation, wherein the diaphragm has a radius less than 5000 μm;   a mounting structure connected to the perimeter of the diaphragm;   an electrode connected to the mounting structure and positioned near a back side of the diaphragm; and   a cavity defined by the back side of the diaphragm, the mounting structure, and the electrode.   
     
     
         6 . The MEMS RF resonator tuner of  claim 6 , wherein the mounting structure comprises silicon. 
     
     
         7 . The MEMS RF resonator tuner of  claim 6 , further comprising a plurality of holes formed in the diaphragm, the holes forming concentric rings in the diaphragm. 
     
     
         8 . The diaphragm of  claim 6 , wherein the diaphragm comprises gold.