| 摘要 |
PURPOSE:To obtain high output power from the semiconductor light emitting element with narrow radiation angle by surrounding the right and left sides of a P type GaAs active layer with P and N type GaAlAs layers and the upper and the lower sides thereof with P type and N type GaAs layers and selecting the refractive index lower than the active layer. CONSTITUTION:P type GaAsAl11, P type GaAs 12 and P type GaAs 13 are laminated on predetermined portions on a P type GaAs substrate 10. P type GaAl As 14 and N type GaAlAs 15 are formed on a substrate 10 in contact with the side surfaces of the layers 11 and 12, and ohmic electrodes 16, 17 are attached thereto. When the electrode 16 is positively biased, a current is branched into the first route of 10-11-13 and the second route of 10-14-15. Since the GaAs has narrower forbidden band width than the GaAlAs, the first route has accordingly lower potential barrier so that a current is selectively flowed, and when aluminum composition is increased, the current is concentrated almost in the first route. When the active layer 12 is suitably selected in thickness (d) and the width W, large light output power can be irradiated in narrow radiation angle. |
