Inorganic/organic hybrid light-emitting diodes (LEDs) (IO-HyLEDs) composed
of p-type GaN/n-type Tris-(8-hydoroxyquinoline) aluminum (Alq3)
were fabricated with and without thin MgO electron-blocking layer (EBL) at
the inorganic/organic interface. These LEDs showed clear and stable current
rectifying diode characteristics and electroluminescence (EL) peaked at UV
region at room temperature. For the sample with MgO-EBL, obvious enhancement
of green emission from Alq3 layer was observed. This result
suggests that due to effective suppression of electron transport from
Alq3 to p-GaN by MgO-EBL, radiative recombination of electrons
and holes in Alq3 layer was enhanced. It was indicated that the
band engineering technique can be applied to control the emission property
of inorganic/organic hybrid LED.