Stacked capacitor and method for preparing the same

Abstract

The present invention discloses a stacked capacitor having interdigital electrodes and method for preparing the same. The stacked capacitor comprises a first interdigital electrode, a second interdigital electrode and a dielectric material sandwiched between the first interdigital electrode and the second interdigital electrode. The first and the second interdigital electrodes comprise a body and a plurality of fingers electrically connected to the body, and the dielectric material can be silicon nitride or silicon oxide. Preferably, fingers of the first interdigital electrode are made of titanium nitride, while fingers of the second interdigital electrode are made of polysilicon. The body of the first and the second interdigital electrodes are preferably made of titanium nitride.

1 . A stacked capacitor, comprising: 
 an upper interdigital electrode;    a lower interdigital electrode; and    a dielectric sandwiched between the upper interdigital electrode and the lower interdigital electrode.    
   
   
       2 . The stacked capacitor of  claim 1 , wherein the upper interdigital electrode and the lower interdigital electrode comprise: 
 a body; and    a plurality of fingers electrically connected to the body.    
   
   
       3 . The stacked capacitor of  claim 2 , wherein the finger of the upper interdigital electrode and the finger of the lower interdigital electrode are made of different materials.  
   
   
       4 . The stacked capacitor of  claim 2 , wherein the finger of the upper interdigital electrode is made of polysilicon or aluminum, and the finger of the lower interdigital electrode is made of titanium nitride or titanium.  
   
   
       5 . The stacked capacitor of  claim 2 , wherein the body and the finger of the upper interdigital electrode are made of different materials.  
   
   
       6 . The stacked capacitor of  claim 2 , wherein the body of the upper interdigital electrode is made of titanium nitride or titanium, and the finger of the upper interdigital electrode is made of polysilicon or aluminum.  
   
   
       7 . The stacked capacitor of  claim 1 , wherein the dielectric constant of the dielectric is larger than or equal to 3.9.  
   
   
       8 . The stacked capacitor of  claim 7 , wherein the dielectric is selected from the group consisting of silicon nitride, silicon oxide, aluminum oxide and titanium oxide.