Simulation for photonic crystal applied to light emittingdiodes and solar cell

• Main Authors: Yao-Te Wang, 王耀德
• Other Authors: Po-Hsun Lei
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/ge8725

碩士 === 國立虎尾科技大學 === 光電與材料科技研究所 === 98 === Recently efficiency of the III-V race compound semiconductor solar cell is lower than the theoretical value. Such result is due to that the solar cell can’t absorb enough solar energy to generate large amount of electron-hole pairs so the efficiency of solar cell can’t increase effectively. Therefore, it is important to increase the area of the solar cell and the junction number to raise the conversion energy. On the other hand, owing to the refractive index difference between semiconductor and air is too high. So that the emission photon will be important to increase to extraction efficiency so that it can enhance the , light output power; There are several method to increase the extraction efficiency such as texture surface with following epoxy package However epoxy package following will reduce relation of brightness and square of refractive index. This paper mainly investigated how to increase the efficiency of solar cell and brightness of Light emitting diodes. Two parts will be discussed include: (a) the simulation of absorbed /emitted and analysis light intensity related to varied size of photonic crystal. (b) the simulation of absorbed /emitted and analysis light intensity related to distance of each photonic crystal. By the simulation results, the emitting intensity of light emitting diodes decrease with decreasing the size of the photonic crystal. On the other hand, the absorbed intensity of the solar cell is also related to the size of photonic crystal. The optimum size and interval of photonic crystal for light emitting diodes is about 300 nm and 3000 nm, respectively. Overall, the use of photonic crystals will effectively enhance the efficiency of solar cells and light emitting diodes. The simulation method for finding the optimum size and distance of each photonic crystal will shorten the experimental interval and cost. In addition, it also increases the R&D efficiency.