Method For Forming Dielectric Film And Method For Forming Capacitor In Semiconductor Device Using The Same

Abstract

Provided is a method for forming a dielectric film in a semiconductor device, wherein the method can improve a dielectric characteristic and a leakage current characteristic. According to specific embodiments of the present invention, the method for forming a dielectric film includes: forming a zirconium dioxide (ZrO2) layer over a wafer in a predetermined thickness that does not allow continuous formation of the ZrO2 layer; and forming an aluminum oxide (Al2O3) layer over portions of the wafer where the ZrO2 layer is not formed, in a predetermined thickness that does not allow continuous formation of the Al2O3 layer

1 . A method for forming a dielectric film, comprising:
 forming a zirconium dioxide (ZrO 2 ) layer over a wafer in a predetermined thickness that does not allow continuous formation of the ZrO 2  layer; and   forming an aluminum oxide (Al 2 O 3 ) layer over portions of the wafer where the ZrO 2  layer is not formed, in a predetermined thickness that does not allow continuous formation of the Al 2 O 3  layer.   
     
     
         2 . The method as recited in  claim 1 , wherein the forming of the ZrO 2  layer includes forming the ZrO 2  layer in a thickness ranging from approximately 1Å to approximately 10 Å that does not allow continuous formation of the ZrO 2  layer. 
     
     
         3 . The method as recited in  claim 1 , wherein the forming of the Al 2 O 3  layer includes forming the Al 2 O 3  layer in a thickness ranging from approximately 1 Å to approximately  10  A that does not allow continuous formation of the Al 2 O 3  layer. 
     
     
         4 . The method as recited in  claim 1 , wherein the dielectric film being a mixed layer of the ZrO 2  layer and the Al 2 O 3  layer is formed to have a thickness ranging from approximately  30  A to approximately 500 Å. 
     
     
         5 . The method as recited in  claim 1 , wherein the forming of the ZrO 2  layer includes:
 supplying a zirconium (Zr) source gas inside a chamber of an atomic layer deposition (ALD) apparatus to adsorb the Zr source gas over the wafer;   supplying an inert gas inside the chamber or using a vacuum pump to purge the Zr source gas which did not become adsorbed;   supplying an oxidation gas inside the chamber to oxidize the adsorbed Zr source gas to form the ZrO 2  layer; and   supplying an inert gas inside the chamber or using a vacuum pump to purge any non-reacted oxidation gas.   
     
     
         6 . The method as recited in  claim 5 , wherein the forming of the ZrO 2  layer is repeatedly performed within a range of forming the ZrO 2  layer to a predetermined thickness that does not allow continuous formation of the ZrO 2  layer over the wafer. 
     
     
         7 . The method as recited in  claim 5 , wherein the forming of the ZrO 2  layer comprises using: the Zr source gas that includes one selected from the group consisting of Zr(O-tBu) 4 , Zr [N(CH 3 ) 2 ] 4 , Zr [N(C 2 H 5 ) (CH 3 )] 4 , Zr [N(C 2 H 5 ) 2 ] 4 , Zr(TMHD) 4 , Zr(OiC 3 H 7 ) 3 (TMTD), and Zr(OtBu) 4 ; the inert gas that includes one of argon (Ar) and nitrogen (N 2 ); and the oxidation gas that includes one selected from the group consisting of water (H 2 O), ozone (O 3 ), and oxygen plasma. 
     
     
         8 . The method as recited in  claim 5 , wherein the forming of the ZrO 2  layer is performed at a temperature ranging from approximately 200° C. to approximately 350° C. 
     
     
         9 . The method as recited in  claim 1 , wherein the forming of the Al 2 O 3  layer includes:
 supplying an aluminum (Al) source gas inside a chamber of an ALD apparatus to adsorb the Al source gas over the wafer;   supplying an inert gas inside the chamber or using a vacuum pump to purge the Al source gas which did not become adsorbed;   supplying an oxidation gas inside the chamber to oxidize the adsorbed Al source gas to form the Al 2 O 3  layer; and   supplying an inert gas inside the chamber or using a vacuum pump to purge any non-reacted oxidation gas.   
     
     
         10 . The method as recited in  claim 9 , wherein the forming of the Al 2 O 3  layer is repeatedly performed within a range of forming the Al 2 O 3  layer to a predetermined thickness that does not allow continuous formation of the Al 2 O 3  layer over the wafer. 
     
     
         11 . The method as recited in  claim 9 , wherein the forming of the Al 2 O 3  layer comprises using: the Al source gas that includes Al(CH 3 ) 3 ; the inert gas that includes one of Ar and N 2 ; and the oxidation gas that includes one selected from the group consisting of H 2 O, O 3 , and oxygen plasma. 
     
     
         12 . A method for forming a dielectric film, comprising:
 forming an Al 2 O 3  layer over a wafer in a predetermined thickness that does not allow continuous formation of the Al 2 O 3  layer; and   forming a ZrO 2  layer over portions of the wafer where the Al 2 O 3  layer is not formed, in a predetermined thickness that does not allow continuous formation of the ZrO 2  layer.   
     
     
         13 . The method as recited in  claim 12 , wherein the forming of the ZrO 2  layer includes forming the ZrO 2  layer in a thickness ranging from approximately 1 Å to approximately 10 Å that does not allow continuous formation of the ZrO 2  layer. 
     
     
         14 . The method as recited in  claim 12 , wherein the forming of the Al 2 O 3  layer includes forming the Al 2 O 3  layer in a thickness ranging from approximately 1 Å to approximately 10 Å that does not allow continuous formation of the Al 2 O 3  layer. 
     
     
         15 . The method as recited in  claim 12 , wherein the dielectric film being a mixed layer of the ZrO 2  layer and the Al 2 O 3  layer is formed to have a thickness ranging from approximately 30 Å to approximately 500 Å. 
     
     
         16 . The method as recited in  claim 12 , wherein the forming of the ZrO 2  layer includes:
 supplying a Zr source gas inside a chamber of an ALD apparatus to adsorb the Zr source gas over the wafer;   supplying an inert gas inside the chamber or using a vacuum pump to purge the Zr source gas which did not become adsorbed;   supplying an oxidation gas inside the chamber to oxidize the adsorbed Zr source gas to form the ZrO 2  layer; and   supplying an inert gas inside the chamber or using a vacuum pump to purge any non-reacted oxidation gas.   
     
     
         17 . The method as recited in  claim 16 , wherein the forming of the ZrO 2  layer is repeatedly performed within a range of forming the ZrO 2  layer to a predetermined thickness that does not allow continuous formation of the ZrO 2  layer over the wafer. 
     
     
         18 . The method as recited in  claim 16 , wherein the forming of the ZrO 2  layer comprises using: the Zr source gas that includes one selected from the group consisting of Zr(O-tBu) 4 , Zr[N(CH 3 ) 2 ] 4 , Zr[N(C 2 H 5 ) (CH 3 )] 4 , Zr[N(C 2 H 5 ) 2 ] 4 , Zr(TMHD) 4 , Zr(OiC 3 H 7 ) 3 (TMTD), and Zr(OtBu) 4 ; the inert gas that includes one of Ar and N 2 ; and the oxidation gas that includes one selected from the group consisting of H 2 O, O 3 , and oxygen plasma. 
     
     
         19 . The method as recited in  claim 16 , wherein the forming of the ZrO 2  layer is performed at a temperature ranging from approximately 200° C. to approximately 350° C. 
     
     
         20 . The method as recited in  claim 12 , wherein the forming of the Al 2 O 3  layer includes:
 supplying an Al source gas inside a chamber of an ALD apparatus to adsorb the Al source gas over the wafer;   supplying an inert gas inside the chamber or using a vacuum pump to purge the Al source gas which did not become adsorbed;   supplying an oxidation gas inside the chamber to oxidize the adsorbed Al source gas to form the Al 2 O 3  layer; and   supplying an inert gas inside the chamber or using a vacuum pump to purge any non-reacted oxidation gas.   
     
     
         21 . The method as recited in  claim 20 , wherein the forming of the Al 2 O 3  layer is repeatedly performed within a range of forming the Al 2 O 3  layer to a predetermined thickness that does not allow continuous formation of the Al?O 3  layer over the wafer. 
     
     
         22 . The method as recited in  claim 20 , wherein the forming of the Al 2 O 3  layer comprises using: the Al source gas that includes Al(CH 3 ) 3 ; the inert gas that includes one of Ar and N 2 ; and the oxidation gas that includes one selected from the group consisting of H 2 O, O 3 , and oxygen plasma. 
     
     
         23 . A method for forming a dielectric film, comprising forming a [ZrO 2 ]x[Al 2 O 3 ]y layer, where ZrO 2  and Al 2 O 3  are mixed, x and y each representing 0 or a positive number, over a wafer using a source gas where a Zr atom and an Al atom are formed as one molecule. 
     
     
         24 . The method as recited in  claim 23 , wherein the forming of the [ZrO 2 ]x[Al 2 O 3 ]y layer includes having the sum of x and y less than approximately 10. 
     
     
         25 . The method as recited in  claim 23 , wherein the dielectric film being a mixed layer of the ZrO 2  layer and the Al 2 O 3  layer is formed to have a thickness ranging from approximately 30 Å to approximately 500 Å. 
     
     
         26 . The method as recited in  claim 23 , wherein the forming of the [ZrO 2 ]x[Al 2 O 3 ]y layer comprises using the source gas that includes ZrAl(MMP) 2 (OiPr) 5 . 
     
     
         27 . The method as recited in  claim 23 , wherein the forming of the [ZrO 2 ]x[Al 2 O 3 ]y layer includes:
 supplying a source gas where a Zr atom and an Al atom are formed as one molecule, inside a chamber of an ALD apparatus to adsorb the source gas over the wafer;   supplying an inert gas inside the chamber or using a vacuum pump to purge the source gas which did not become adsorbed;   supplying an oxidation gas inside the chamber to oxidize the adsorbed source gas to form the [ZrO 2 ]x[Al 2 O 3 ]y layer; and   supplying an inert gas inside the chamber or using a vacuum pump to purge any non-reacted oxidation gas.   
     
     
         28 . A method for forming a capacitor, comprising:
 preparing a substrate structure on which a contact plug is formed;   forming a patterned insulation layer over the substrate structure in a manner to expose the contact plug;   forming a bottom electrode over the patterned insulation layer and the substrate structure;   forming a dielectric film over the bottom electrode using a method claimed in one of  claim 1  to  claim 27 ; and   forming an upper electrode over the dielectric film.   
     
     
         29 . The method as recited in  claim 28 , further comprising performing a thermal treatment process to the dielectric film after the dielectric film is formed, wherein the thermal treatment process is performed in an atmosphere of Ar, N 2  or oxygen (O 2 ) at a temperature ranging from approximately 450° C. to approximately 850° C.