Blue-green InGaN/GaN light-emitting diode with mesh-like top metal electrode

- Blue-green light-emitting diodes with mesh-like electrode demonstrate broad EL-spectrum.
- In EL-spectrum blue and green emission peaks are equal with shallow trough between them.
- Observed EL-spectrum is related to spatially nonuniform current injection.
- Position-dependent compensation of quantum-confined Stark effect takes place.

Light-emitting diodes (LEDs) with blue-green dual-wavelength emission and top metal electrode patterned as a mesh were fabricated using InGaN/GaN material system and tested. In pulsed voltage supply mode an increase in injected current resulted in electroluminescence (EL) with equal peak intensities of blue and green emission lines and shallow trough between them. These features of the LED EL-spectrum can be attributed to the effect of the mesh-like patterning of the top electrode.Meshed electrode promotes the injection of current spatially nonuniform along the planes of the quantum well (QWs) which results not only in spatial nonuniformity of the intensity of generated light but also may contribute to position-dependent compensation of Quantum-confined Stark effect (QCSE) resulting in blue shift of EL in the QWs. The observed phenomenon can be used to control or engineer the EL spectra of dual-wavelength LEDs by electrode patterning.

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