PARAMAGNETIC-RESONANCE IN GAN-BASED SINGLE QUANTUM-WELLS

We report electrically-detected magnetic resonance (EDMR) and electrol uminescence-detected magnetic resonance (ELDMR) results on InGaN/AlCaN single-quantum-well light emitting diodes. The dominant feature detec ted by either technique is a broad resonance (Delta B approximate to 1 3 mT) at g approximate to 2.01 due to a deep defect. Depending on bias , this defect results in either an increase or a decrease in electrolu minescence at resonance while the EDMR gives a current enhancement at resonance. Based on a comparison of signal intensities for the two mea surements, we conclude that this defect is present in at least two loc ations: (1) a nonradiative recombination path, in parallel with the ra diative recombination path, and (2) a recombination channel in the dep letion region of one of the contacts. A second resonance with g approx imate to 1.99 and Delta B approximate to 7 mT is very similar to the d eep donor trap, previously observed in double heterostructure diodes, and produces a decrease in both the current and electroluminescence at resonance. (C) 1997 American Institute of Physics.