Apparatuses and methods for controlling structure of bottom electrodes and providing a top-support thereof

Abstract

An apparatus includes: a substrate; a plurality of pillar-shaped bottom electrodes provided over the substrate; and an upper electrode covering side and top surfaces of the pillar-shaped bottom electrodes with an intervening capacitor insulating film therebetween. The pillar-shaped bottom electrodes have at least an upper portion and a lower portion. The diameter of the upper portion is smaller than the diameter of the lower portion.

1 . An apparatus comprising:
 a substrate;   a plurality of pillar-shaped bottom electrodes provided over the substrate; and   an upper electrode covering side and top surfaces of the plurality of pillar-shaped bottom electrodes with an intervening capacitor insulating film therebetween;   wherein each of the plurality of pillar-shaped bottom electrodes has at least an upper portion and a lower portion, and wherein the diameter of the upper portion is smaller the diameter of the lower portion.   
     
     
         2 . The apparatus of  claim 1 , wherein the lower portion is provided at the upper end of each of the pillar-shaped bottom electrodes. 
     
     
         3 . The apparatus of  claim 1 , wherein a step is provided at a boundary between the upper portion and the lower portion. 
     
     
         4 . The apparatus of  claim 1 , wherein the pillar-shaped bottom electrodes are supported by a beam provided between the pillar-shaped bottom electrodes. 
     
     
         5 . The apparatus of  claim 1 , wherein the pillar-shaped bottom electrodes are connected by a beam in the upper portion. 
     
     
         6 . The apparatus of  claim 1 , wherein the pillar-shaped bottom electrodes, the capacitor insulating film, and the upper electrode form a capacitor. 
     
     
         7 . The apparatus of  claim 1 , wherein the pillar-shaped bottom electrodes include a conductive material. 
     
     
         8 . A method comprising:
 forming a plurality of pillar-shaped bottom electrodes over a substrate, wherein each of the plurality of pillar-shaped bottom electrodes has at least an upper portion and a lower portion;   forming an upper electrode covering side and top surfaces of the plurality of pillar-shaped bottom electrodes with an intervening capacitor insulating film therebetween; and   etching the upper portions of the plurality of pillar-shaped bottom electrodes such that a diameter of the upper portion is smaller a diameter of the lower portion.   
     
     
         9 . The method of  claim 8 , wherein the upper electrode is formed by chemical vapor deposition (CVD). 
     
     
         10 . The method of  claim 8 , wherein the lower portion is provided at the upper end of each of the pillar-shaped bottom electrodes. 
     
     
         11 . The method of  claim 8 , further comprising:
 forming a step at a boundary between the upper portion and the lower portion.   
     
     
         12 . The method of  claim 8 , further comprising:
 forming a first insulating film over the substrate;   forming a second insulating film on the first insulating film;   forming a third insulating film on the second insulating film, wherein the third insulating film having a plurality of openings;   forming a fourth insulating film on the third insulating film; and   forming a fifth insulating film on the fourth insulating film.   
     
     
         13 . The method of  claim 12 , further comprising forming a plurality of holes, wherein forming the plurality of holes comprises:
 patterning the fifth insulating film;   using the patterned fifth insulating film as an etching mask to sequentially etch the fourth insulating film, the third insulating film, the second insulating film, and the first insulating film;   penetrating from a top surface of the fifth insulating film to a bottom face of the first insulating film to form the plurality of holes; and   removing the fifth insulating film.   
     
     
         14 . The method of  claim 13 , wherein the holes of the plurality of holes are arranged in a staggered layout. 
     
     
         15 . The method of  claim 13 , further comprising:
 filling each of the plurality of holes with a conductive material to form the plurality of pillar-shaped bottom electrodes.   
     
     
         16 . The method of  claim 8 , further comprising:
 partially etching the exposed upper portions of the plurality of pillar-shaped bottom electrodes to increase a distance between the exposed upper portions of the pillar-shaped bottom electrodes adjacently arranged.   
     
     
         17 . An apparatus comprising:
 a substrate;   a first insulating film over the substrate;   a second insulating film on the first insulating film;   a third insulating film on the second insulating film, wherein the third insulating film has a plurality of openings;   a fourth insulating film on the third insulating film;   a fifth insulating film on the fourth insulating film;   a plurality of first holes reaching from an upper surface of the fifth insulating film to a bottom surface of the first insulating film; and   a plurality of pillar-shaped bottom electrodes in the plurality of first holes, wherein each of the plurality of pillar-shaped bottom electrodes has at least an upper portion and a lower portion, and wherein the diameter of the upper portion is smaller the diameter of the lower portion.   
     
     
         18 . The apparatus of  claim 17 , further comprising:
 an upper electrode covering side and top surfaces of the plurality of pillar-shaped bottom electrodes with an intervening capacitor insulating film therebetween.   
     
     
         19 . The apparatus of  claim 17 , further comprising a plurality of second holes penetrating the second insulating film, wherein the second insulating film is configured to support the plurality of pillar-shaped bottom electrodes. 
     
     
         20 . The apparatus of  claim 17 , wherein the first insulating film and the third insulating film are made of a first material, and wherein the second insulating film and the fourth insulating film are made of the same.