Method of forming a phase changeable structure

Abstract

The present invention relates to a method of forming a phase changeable structure wherein an upper electrode is formed on a phase changeable layer. A material including fluorine can be provided to the phase changeable layer and the upper electrode. The phase changeable layer can be etched to form a phase changeable pattern. Oxygen plasma or water vapor plasma can then be provided to the upper electrode and the phase changeable pattern.

1 . A method of forming at least part of a phase changeable structure, the method comprising:
 forming a phase changeable layer on a lower electrode;   forming a conductive layer on the phase changeable layer;   etching the conductive layer and at least a portion of the phase changeable layer with a first material having a chlorine-containing compound and a fluorine-containing compound to form an upper electrode and at least a portion of a phase changeable pattern; and   exposing the upper electrode and the phase changeable pattern to a second material having an oxygen-containing compound.   
   
   
       2 . The method of  claim 1 , further comprising a step of evacuating substantially all of the first material before the exposing step. 
   
   
       3 . The method of  claim 1 , wherein the oxygen-containing compound is selected from the group consisting of oxygen plasma, water vapor plasma, and mixtures thereof. 
   
   
       4 . The method of  claim 1 , wherein the exposing step is conducted at a temperature of less than about 150° C. 
   
   
       5 . The method of  claim 1 , wherein the exposing step is conducted in situ. 
   
   
       6 . The method of  claim 1 , wherein the phase changeable layer comprises a calcogenide selected from the group consisting of germanium, antimony, tellurium, and any combination thereof. 
   
   
       7 . The method of  claim 1 , wherein the conductive layer comprises a metal selected from the group consisting of tungsten, titanium, titanium nitride, tantalum, tantalum nitride, molybdenum nitride, niobium nitride, titanium silicon nitride, aluminum, titanium aluminum nitride, titanium boron nitride, zirconium silicon nitride, tungsten silicon nitride, tungsten boron nitride, zirconium aluminum nitride, molybdenum silicon nitride, molybdenum aluminum nitride, tantalum silicon nitride, tantalum aluminum nitride, copper, aluminum copper, alloys thereof, and any combination thereof. 
   
   
       8 . The method of  claim 1 , wherein the fluorine-containing compound is selected from the group consisting of tetrafluoromethane, trifluoromethane, difluoromethane, monofluoromethane, and any combination thereof. 
   
   
       9 . The method of  claim 1 , wherein the first material further includes a diluent compound in a plasma state. 
   
   
       10 . The method of  claim 9 , wherein the diluent compound is selected from the group consisting of helium, neon, argon, krypton, xenon, radon or any combination thereof. 
   
   
       11 . A phase changeable structure obtained from the method of  claim 1 , wherein the structure shows decreased damage of the phase changeable pattern.