Electric field sensor with electrode interleaving vibration

Abstract

An electric field sensor comprising: a substrate having a hole; a shielding electrode and a sensing electrode, disposed in the hole of the substrate; a piezoelectric bar having one end connected to the center of the shielding electrode, the other end fixed on the substrate. Present invention provides several electric field sensors, which have the same feature of utilizing electrodes interleaving vibration to modulate external electric field. They have IC-compatible operation voltage and small volume.

1 . An electric field sensor comprising: 
 A substrate having a hole;    A shielding electrode and a sensing electrode, disposed in the hole of the substrate;    A piezoelectric bar having one end connected to the center of the shielding electrode, the other end fixed on the substrate.    
   
   
       2 . The electric field sensor according to  claim 1 , wherein said the sensing electrode has a rectangle rim with comb fingers inside, the shielding electrode is a comb shape.  
   
   
       3 . The electric field sensor according to  claim 1 , further comprising 
 colloidal material interposed between the substrate and the other end of the piezoelectric bar.    
   
   
       4 . The electric field sensor according to  claim 1 , wherein said the shape of the substrate can be rectangle, round, echelon or other shapes.  
   
   
       5 . The electric field sensor according to  claim 1 , wherein said shielding electrode and said sensing electrode are made of conductors.  
   
   
       6 . The electric field sensor according to  claim 5 , wherein said conductor is doping silicon.  
   
   
       7 . The electric field sensor according to  claim 1 , wherein said piezoelectric bar is a shape memory alloy.  
   
   
       8 . An electric field sensor comprising: 
 a substrate having an insulating surface;    at least two anchors being fixed on the insulating surface;    at least two thermal actuators integrated with the anchors.    a shielding electrode and a sensing electrode being comb shape, the shielding electrode supported by the thermal actuators .    
   
   
       9 . The electric field sensor according to  claim 8 , wherein said thermal actuators are made of polysilicon or other conductive materials.  
   
   
       10 . The electric field sensor according to  claim 8 , wherein said the shape of anchors is square, rectangle, round or triangle and any other shape.  
   
   
       11 . The electric field sensor according to  claim 8 , wherein said top surface of shielding electrode is lower than said top surface of sensing electrode.  
   
   
       12 . The electric field sensor according to  claim 8 , wherein said shielding electrode and thermal actuators are integrated.  
   
   
       13 . The electric field sensor according to  claim 8 , wherein said thermal actuators being clamp-clamp beam.  
   
   
       14 . The electric field sensor according to  claim 13 , wherein at least one clamp-clamp beam for supporting the shielding electrode,  
   
   
       15 . The electric field sensor according to  claim 8 , wherein said thermal actuator being a U-shape thermal actuators.  
   
   
       16 . The electric field sensor according to  claim 14 , wherein said U-shape thermal actuator consisted of top layer, bottom layer and connector.  
   
   
       17 . The electric field sensor according to  claim 15 , wherein said connector sandwiched between the top layer and bottom layer.  
   
   
       18 . The electric field sensor according to  claim 14 , wherein a beam connected to the top layer between each pair of thermal actuators.  
   
   
       19 . The electric field sensor according to  claim 14 , further comprising: 
 adding a new beam under the original beam, which is connected to the bottom layer.    
   
   
       20 . The electric field sensor according to  claim 18 , wherein said new beam connected to the bottom layer between each pair of thermal actuators, while the original beam would be deleted.  
   
   
       21 . The electric field sensor according to  claim 15 , wherein said the top layer and bottom layer being made of polysilicon.  
   
   
       22 . The electric field sensor according to  claim 15 , wherein said at least one U-shaped thermal actuator for supporting the shielding electrode.  
   
   
       23 . The electric field sensor according to  claim 8 , wherein said thermal actuator being an electromagnetic actuator.  
   
   
       24 . The electric field sensor according to  claim 8 , wherein said actuation includes piezoelectric actuation, electrostatic actuation and magnetic actuation.