| 摘要 |
PROBLEM TO BE SOLVED: To provide an LED structure which is capable of reducing a light loss to an irreducible minimum at a mesa wall. SOLUTION: The mesa wall of a III nitride flip chip light emitting device is varied in a refractive index. A variation in a refractive index enables most of light incident on a mesa wall to be reflected toward the device, so that light can be effectively extracted. In some practical forms, a solder wall on a sub-mount or a gel which has a high refractive index and covers the light emitting device and the sub-mount generates a hermetically sealed gap between the light emitting device and the sub-mount. The gap is filled up with material having a low refractive index. In the other practical form, the board of a light emitting device is covered with material of high refractive index, and a gap between the sub-mount and the light emitting device is filled up with material having a low refractive index. |
