Method for chemical planarization and chemical planarization apparatus

Abstract

According to one embodiment, a method for chemical planarization includes: preparing a treatment liquid containing a hydrosilicofluoric acid aqueous solution containing silicon dioxide dissolved therein at a saturated concentration; and decreasing height of irregularity of a silicon dioxide film. In the decreasing, dissolution rate of convex portions is made larger than dissolution rate of concave portion of the irregularity while changing equilibrium state of the treatment liquid at areas being in contact with the convex portions of the irregularity, in a state in which the silicon dioxide film having the irregularity is brought into contact with the treatment liquid.

1 - 20 . (canceled) 
     
     
         21 . A chemical planarization apparatus comprising:
 a treatment container configured to store a to-be-treated substrate provided with a silicon dioxide film having irregularity, the irregularity including a concave and a convex portion of silicon dioxide;   a treatment liquid supplying part configured to supply a treatment liquid in the treatment container, the treatment liquid containing a hydrosilicofluoric acid aqueous solution containing silicon dioxide dissolved in the hydrosilicofluoric acid aqueous solution at a saturated concentration;   an equilibrium changing part including a temperature controlling plate being capable of being cooled,   the equilibrium changing part being configured to make a first dissolution rate larger than a second dissolution rate to remove at least a part of the silicon dioxide at the convex portion and decrease a distance between a top surface of the silicon dioxide at the convex portion and a top surface of the silicon dioxide at the concave portion, the making being performed by changing equilibrium state of the treatment liquid at areas being in contact with the convex portion in a state in which the silicon dioxide film is brought into contact with the treatment liquid, the first dissolution rate being a dissolution rate of the silicon dioxide at the convex portion with respect to the treatment liquid, and the second dissolution rate being a dissolution rate of the silicon dioxide at the concave portion with respect to the treatment liquid,   the changing equilibrium state including carrying out treatment of decreasing temperature of the convex portions by bringing the temperature controlling plate into contact with the convex portions.   
     
     
         22 . The apparatus according to  claim 21 , wherein the treatment liquid substantially contains no abrasive grain. 
     
     
         23 . The apparatus according to  claim 21 , wherein the contact of the silicon dioxide film with the temperature controlling plate includes changing a relative position between the silicon dioxide film and the treatment plate. 
     
     
         24 . The apparatus according to  claim 21 , wherein the equilibrium changing part further includes an exudation plate capable of exuding hydrofluoric acid, and
 the changing equilibrium state further includes carrying out treatment of supplying hydrofluoric acid toward the convex portion by bringing the exudation plate into contact with the convex portion.   
     
     
         25 . The apparatus according to  claim 24 , wherein the exudation plate includes a porous structure. 
     
     
         26 . The apparatus according to  claim 21 , wherein the equilibrium changing part further includes a catalyst plate, and
 the changing equilibrium state further includes carrying out treatment of generating fluorine ions (F − ) near the convex portion from the treatment liquid by bringing the catalyst plate into contact with the convex portion.   
     
     
         27 . The apparatus according to  claim 26 , wherein the catalyst plate includes at least one of platinum, a platinum ruthenium alloy, a rare earth metal, a compound of a rare earth metal, cobalt, a compound of cobalt, and a carbon compound of cobalt. 
     
     
         28 . The apparatus according to  claim 21 , wherein the equilibrium changing part further includes an electrode plate, and
 the changing equilibrium state further includes carrying out treatment of generating hydrofluoric acid from the treatment liquid by bringing the electrode plate into contact with the convex portion and by applying a voltage to the convex portions to supply charges near the convex portion.   
     
     
         29 . The apparatus according to  claim 28 , wherein the charges contain electrons. 
     
     
         30 . The apparatus according to  claim 21 , wherein the decreasing height of the irregularity further includes generating precipitation of silicon dioxide on the concave portion by changing equilibrium state of the treatment liquid. 
     
     
         31 . The apparatus according to  claim 21 , wherein bringing the silicon dioxide film into contact with the treatment liquid includes immersing the silicon dioxide film in the treatment liquid. 
     
     
         32 . The apparatus according to  claim 21 , wherein a distance between upper face of the convex portion and lower face of the concave portion is not less than 30 nm and not more than 2 μm. 
     
     
         33 . The apparatus according to  claim 21 , further comprising forming the silicon dioxide film by a chemical vapor deposition method, or a coating method.