Light Extraction Efficiency Improvement Techniques in Light-Emitting Diodes

This chapter presents an overview of the rapid progress being made in light-emitting diode (LED) devices for enhancing their optical and electrical properties. Over the past few decades, major electronic companies have been developing III-V semiconductor material LED devices like multiple quantum well (MQW)-based LED devices using different methodologies because of the factor ‘efficiency droop’, which affects the luminous efficiency of the device. Internal quantum efficiency (IQE) of III-V-based LED increases at less current density (J) and decreases at the current densities that are required to operate power LEDs, called efficiency droop. Minimizing the efficiency droop using different design methodologies was performed by managing the polarization field, achieving uniform carrier injection distribution across the active region, and minimizing the carrier leakage. III-V material-based LED devices have also been developed by commercial companies for visible light and solid state applications.