Efficient Eu-related photoluminescence was observed from Eu doped GaN grown
by gas-source molecular beam epitaxy using ammonia as a nitrogen source on
Al2O3(0001) or Si(111) substrates. Photoluminescence spectra from Eu doped
GaN show red emission at 622 nm which can be assigned as D-5(0)-F-7(2) tra
nsition of EU3+ ion. The effects of the growth conditions and substrates on
the luminescence intensity were studied, and the emission mechanism was su
ggested based on the photoluminescence excitation spectra. Room temperature
operation of MIS diodes composed of Eu doped GaN were demonstrated.