Organic memory device using iridium organometallic compound and fabrication method thereof

Abstract

Disclosed are a composition comprising a mixture of at least one iridium organometallic compound and an electrically conductive polymer, an organic active layer comprising the same, an organic memory device comprising the organic active layer and methods for fabricating the same. The organic memory device may include a first electrode, a second electrode and the organic active layer between the first and second electrodes. The organic memory device possesses the advantages of rapid switching time, decreased operating voltage, decreased fabrication costs, increased reliability and improved non-volatility.

1 . A composition comprising a mixture of an electrically conductive polymer and at least one iridium organometallic compound represented by Formula 3: 
       
         
           
           
               
               
           
         
         wherein R 1  and R 2 , which are identical to or different from each other, are independently H, a substituted or unsubstituted C 1 -C 20  alkyl group, a substituted or unsubstituted C 1 -C 20  alkoxy group, a substituted or unsubstituted C 3 -C 20  cycloalkyl group, a substituted or unsubstituted C 3 -C 20  heterocycloalkyl group, a substituted or unsubstituted C 6 -C 30  aryl group, a substituted or unsubstituted C 4 -C 30  heteroaryl group, a substituted or unsubstituted C 7 -C 30  arylalkyl group, or a substituted or unsubstituted C 6 -C 30  aryloxy group. 
       
     
     
         2 . The composition according to  claim 1 , wherein the iridium organometallic compound has a maximum emission wavelength of about 450 nm to about 550 nm. 
     
     
         3 . The composition according to  claim 2 , wherein the iridium organometallic compound has a maximum emission wavelength of about 480 nm to about 530 nm. 
     
     
         4 . The composition according to  claim 1 , wherein the electrically conductive polymer is at least one polymer selected from the group consisting of polythiophene, polyacetylene, polyporphyrin, polyvinylcarbazole, polyaniline, polypyrrole, polyphenylenevinylene, polyfluorene, poly(3-hexylthiophene), polynaphthalene, poly(p-phenylene sulfide), polyvinylpyridine, polyferrocene, and polystyrol. 
     
     
         5 . An organic active layer comprising the composition according to  claim 1 . 
     
     
         6 . An organic memory device comprising a first electrode, a second electrode and the organic active layer according to  claim 5  between the first and second electrodes. 
     
     
         7 . The organic memory device according to  claim 6 , wherein the first or second electrode is made of at least one material selected from the group consisting of gold, silver, platinum, copper, cobalt, nickel, tin, titanium, tungsten, aluminum, and indium tin oxide (ITO). 
     
     
         8 . The organic memory device according to  claim 6 , further comprising:
 a barrier layer on the first electrode or under the second electrode.   
     
     
         9 . The organic memory device according to  claim 8 , wherein the barrier layer is made of an inorganic material selected from the group consisting of SiO x , AlO x , NbO x , TiO x , CrO x , VO x , TaO x , CuO x , MgO x , WO x  and AlNO x , or an organic material selected from the group consisting of Alq3, polymethylmethacrylate, polystyrene and PET. 
     
     
         10 . The organic memory device according to  claim 9 , wherein the barrier layer is formed of a material selected from the group consisting of SiO 2 , Al 2 O 3 , Cu 2 O, TiO 2  and V 2 O 3 . 
     
     
         11 . A method for fabricating an organic active layer comprising:
 forming the organic active layer using a mixture of an electrically conductive polymer and at least one iridium organometallic compound represented by Formula 3:   
       
         
           
           
               
               
           
         
         wherein R 1  and R 2 , which are identical to or different from each other, are independently H, a substituted or unsubstituted C 1 -C 20  alkyl group, a substituted or unsubstituted C 1 -C 20  alkoxy group, a substituted or unsubstituted C 3 -C 20  cycloalkyl group, a substituted or unsubstituted C 3 -C 20  heterocycloalkyl group, a substituted or unsubstituted C 6 -C 30  aryl group, a substituted or unsubstituted C 4 -C 30  heteroaryl group, a substituted or unsubstituted C 7 -C 30  arylalkyl group, or a substituted or unsubstituted C 6 -C 30  aryloxy group. 
       
     
     
         12 . The method according to  claim 11 , wherein the iridium organometallic compound has a maximum emission wavelength of about 450 nm to about 530 nm. 
     
     
         13 . The method according to  claim 12 , wherein the iridium organometallic compound has a maximum emission wavelength of about 480 nm to about 500 nm. 
     
     
         14 . The method according to  claim 12 , wherein the electrically conductive polymer is at least one polymer selected from the group consisting of polythiophene, polyacetylene, polyporphyrin, polyvinylcarbazole, polyaniline, polypyrrole, polyphenylenevinylene, polyfluorene, poly(3-hexylthiophene), polynaphthalene, poly(p-phenylene sulfide), polyvinylpyridine, polyferrocene, and polystyrol. 
     
     
         15 . The method according to  claim 11 , wherein the organic active layer is formed using a coating solution of the iridium organometallic compound and the electrically conductive polymer in a solvent by a process selected from spin coating, spray coating, electrostatic coating, dip coating, blade coating, roll coating, and inkjet printing. 
     
     
         16 . The method according to  claim 15 , wherein the solvent is selected from the group consisting of chloroform, N-methylpyrrolidone, acetone, cyclopentanone, cyclohexanone, methyl ethyl ketone, ethyl cellosolve acetate, butyl acetate, ethylene glycol, toluene, xylene, tetrahydrofuran, dimethylformamide, chlorobenzene, acetonitrile, and mixtures thereof. 
     
     
         17 . A method of fabricating an organic memory device comprising:
 forming a first electrode and a second electrode; and   forming the organic active layer according to  claim 11  between the first and second electrodes.   
     
     
         18 . The method according to  claim 17 , further comprising:
 forming a barrier layer on the first electrode or under the second electrode.