Organic electroluminescent device comprising electron shower treated hole injection layer and method for preparing the same

A method for preparing an organic electroluminescent device, comprising:

• forming an anode on a substrate;
• forming a hole injection layer on the anode;
• performing an electron shower treatment on the hole injection layer;
• forming an emitting layer on the hole injection layer;
• and
• forming a cathode on the emitting layer.

A method for preparing an organic electroluminescent device, comprising:

• forming an anode on a substrate;
• forming a hole injection layer on the anode;
• removing impurities or unstable ions from the hole injection layer;
• forming an emitting layer on the hole injection layer;
• and
• forming a cathode on the emitting layer.