Characteristics of organic light emitting diodes with tetrakis(Ethylmethylamino) hafnium treated indium tin oxide

The surface of indium tin oxide (ITP) in organic light emitting diodes (PLEDs) was treated using an atomic layer deposition with tetrakis(ethylmethylamino) hafnium (TEMAH) and O₂ precursors. The treatment for 5 cycles at room temperature resulted in a significant improvement in the electroluminescent characteristics resulting from the increased hole injection. According to the various characterizations, an ultra-thin HfO _x layer without any insulating properties was formed, which modified the electronic band structure of the ITP anode. When the number of cycles or temperature was increased, an electrically insulating HfO_x was formed, and the resulting PLED properties deteriorated.