Analyzing the physical properties of InGaN multiple quantum well light emitting diodes from nano scale structure

We report on the influence of nanoscale indium fluctuations on physical properties for multiple quantum well (QW) light emitting diodes (LEDs). A commercial grade c-plane LED was analyzed by atom probe tomography, and the indium composition distribution was extracted. The influence of the degree of fluctuation and number of quantum wells were analyzed by a two-dimensional Poisson and drift-diffusion solver with very fine mesh and compared to the experimental result and a simple normal quantum well model. The studies show that the indium fluctuation will significantly impact the device's internal quantum efficiency, droop behavior, and current-voltage curves. Including the influence of indium-fluctuation gives a better prediction of the device performance.