Study of the light efficiency from GaN light-emitting diodes with two-dimensional photonic crystal

• Main Authors: Fu-an Du, 杜福安
• Other Authors: Jen-Inn Chyi
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/zupq78

碩士 === 國立中央大學 === 光電科學研究所 === 94 === Abstract In this research, we study the light extraction characteristics in photonic crystal slab structures and report the enhancement results. There are two mechanisms for improved LED output power, the first is using the Bragg scattering to enhance the output efficiency by photonic crystal surface patterned and it can avoid the internal reflection probability to occur. The second mechanism is permitting the guided mode to the escape the LED slab by the photonic crystal band gap structure. Besides it, we consider the reduced emitting area and non-radiative recombination effect when photonic crystal structure inset the LED device. We also consider the resonant structure which induced the Purcell effect, and it can enhance the spontaneous emission rate. Finally, we set up a model that can describe the light characteristics in the photonic crystal LED structure.