Solution-processed sol-gel films including a crystallization aid, devices including same, and methods
View Patent ↗A method for preparing a sol-gel film is disclosed. The method comprises providing a sol-gel composition comprising one or more sol-gel film precursors and a crystallization aid, and processing the sol-gel composition by solution processing to form the sol-gel film. In certain embodiments, the sol-gel film comprises one or more metal oxides. A preferred crystallization aid includes triphenylphosphine oxide. A composition for making a sol-gel film, a sol-gel film, a device including a sol-gel film and a method for making such device are also disclosed.
1. A method for fabricating a sol-gel film comprising zinc oxide, the method comprising:
providing a sol-gel composition comprising one or more zinc oxide precursors, a crystallization aid comprising a phenyl phosphine oxide compound, and a solvent, wherein the solvent comprises an alcohol or a mixture of alcohols; and
processing the sol-gel composition by solution processing to form the sol-gel film.
2. A method in accordance with claim 1 , wherein a zinc oxide precursor comprises a zinc salt.
3. A method in accordance with claim 1 , wherein the sol-gel film is formed at a temperature less than about 200° C.
4. A method in accordance with claim 1 , wherein the crystallization aid comprises a triphenylphosphine oxide compound.
5. A method in accordance with claim 1 , wherein the phenyl phosphine oxide compound comprises triphenyl phosphine oxide, bis(4-fluorophenyl) phenyl phosphine oxide, decyl(diphenyl) phosphine oxide, benzyl(diphenyl)phosphine oxide, [2-(diphenylphosphoryl)ethyl](diphenyl) phosphine oxide, or a combination thereof.
6. A method in accordance with claim 5 , wherein the phenyl phosphine oxide comprises triphenyl phosphine oxide.
7. A sol-gel composition comprising:
a sol-gel film precursor comprising
a zinc oxide precursor,
a crystallization aid comprising a phenyl phosphine oxide compound, and a solvent comprising an alcohol or a mixture of alcohols.
8. A sol-gel composition in accordance with claim 7 wherein the crystallization aid is included in the sol-gel composition at a concentration less than or equal to 0.05M.
9. A sol-gel composition in accordance with claim 7 wherein the crystallization aid is included in the sol-gel composition in an amount in a range from about 0.1 to about 10 weight percent of the weight of the sol-gel film precursor.
10. A sol-gel composition in accordance with claim 9 wherein the sol-gel film precursor comprises a zinc salt and the crystallization aid comprises a triphenylphosphine oxide compound.
11. A sol-gel composition in accordance with claim 7 wherein the crystallization aid is included in the sol-gel composition in an amount in a range from about 0.2 to about 6 weight percent of the weight of the sol-gel film precursor.
12. An optoelectronic device comprising:
a cathode;
an electron transport layer, wherein the electron transport layer comprises a sol-gel film comprising zinc oxide; and a crystallization aid comprising a phenyl phosphine oxide compound;
a light-emitting layer;
a hole transport layer;
a hole injection layer; and
an anode.