| abstract |
An organic light-emitting device, comprising a substrate; an anode and a cathode; a first hole-transport layer provided over the anode and having at least a first material; a second hole-transport layer provided over the first hole-transport layer, and having at least a second material; at least one light-emitting layer disposed over the second hole-transport layer wherein the light-emitting layer(s) includes a host, a dopant, and a hole-trapping material; an improved electron-transport layer disposed between the light-emitting layer(s) and the cathode. |