Study Of Surface Plasmon Polariton Effects In Heterojunction Interface Of GaN

Since the Gallium nitride (GaN) was manufactured in1980s, the GaN has triggered a series of researches. As a typical third-generation semiconductor material, the Gallium nitride has a wide applications in anti-radiation, high frequency, high power, high density integrated electronics and optical detective devices. Since the GaN-based blue LED emerged, GaN has play an important role in the device applications (such as LEDs).The high-power output of light is essential to extend the applications of the GaN-devices, while the current light extraction efficiency is very low. The low efficiency has the internal and external factors. Owing to the optimization for the Group Ⅲ nitride material, the emitting efficiency had been improved, but the transmission efficiency is still low. So studying the transmitting light in the GaN to improve the extraction efficiency is very essential to increase the GaN’s applications in optoelectronic components, light display and optoelectronic integrated industry.When the light lies on metal, there’s the surface plasmon polaritons (SPPs) on the metal surface sometimes. Thanks to the interaction between the photons and the free electrons, the incident light is absorbed, and a local intensity enhancement occurs near the metal. According to the SPPs theories, we can enhance the light intensity by the nano-sized metal structure in GaN. In recent years, many researches had been done. The intensity of blue light had been enhanced by more than a dozen times, however, the result was only about1times for the yellow and green light which is the most sensitive for eyes. And their models had high cost, and complicated structure. So we proposed a model, which is simpler and cheaper to reach the enhancement, and the efficiency is better.Firstly, we analyzed the SPPs to provide the theoretical foundation. Secondly, we introduced the numerical simulation methods. Thirdly, we proposed the model, reached exciting the SPPs in the GaN material. We calculated and analyzed the structure with different parameters, and studied the numerical simulation results of Ag-films/Al-films/Au-films. With a simple Al or Ag basic grating structure, the7.4～7.6times intensity of550nm light can be obtained easily, and the enhancement efficiency is better than others.