Design of a voltage-tunable tricolor (Blue/Cyan/Green) monolithic solid state LED

Voltage-controlled tricolor monolithic (single) solid state LED has been presented in this paper. This work will be used for light emissions of different colors controlled with the step changes of supplied potentials. The monolithic structure of Indium Gallium Nitride (InGaN)-based double Quantum Well (DQW) light-emitting diode (LED) has been designed and simulated with SILVACO Technology Computer Aided Design (TCAD). Electron-hole recombination and illumination in each quantum well dominate at specific applied potentials. The spectral power distribution, electrons and holes concentrations in the active regions, energy band diagrams and power conversion efficiency for the solid-state lighting (SSL) structure are investigated. Effects of doping concentration in decoupling region, indium content in the InGaN alloy and active layers thicknesses, on the emission spectra are critical design parameters for optimum performance and desired control of the device. The simulated results indicate that an LED with an optimized structure can be produced from blue to cyan and then green light emissions with the tuning of supply voltage.