Calculation of light extraction efficiency or optical output coupling efficiency is often needed in simulating a light emitting device (LED) such as an organic LED (OLED). It is best to perform these calculations without running electrical simulation in the device, as parameters for new materials are hard to obtain and generally unnecessary in calculating light extraction efficiency. Moreover, a pure optical simulation will save simulation time and avoid any potential un-convergence in the electrical simulation.

Silicon carbide is expected to be an excellent device material as high voltage and low-loss power devices. Recently, SBD (Schottky Barrier Diode) and MOSFET based on silicon carbide have been realized [1-3], however, those devices have some problems for its reliability and control of the IV characteristics. The problems are related to defects in the bulk and at the interface of insulator/semiconductor. The concentration (~5e12[/cm3]) of the defects is 2 orders higher than that of silicon [4], and so the defects cause degradation of device characteristics. The investigation of the defect property is important for the improvement of the device performance.