Organic light emitting diode display device and method of fabricating the same

An organic light emitting diode (OLED) display device, comprising:

• a first electrode formed on a substrate;
• a first hole injection layer, a first hole transport layer, a first light emitting layer, a first electron transport layer, and a first buffer layer laminated on the substrate;
• a second hole injection layer, a second hole transport layer, a second light emitting layer, a second electron transport layer, and a second buffer layer laminated on the substrate;
• a third hole injection layer, a third hole transport layer, a third light emitting layer, a third electron transport layer, and a third buffer layer laminated on the substrate;
• and
• a second electrode formed on the first, second, and third buffer layers, wherein the first, second, and third buffer layers are made of a metal oxide.