Superluminescent diode with offset current injection regions

摘要

A superluminescent diode includes a semiconductor substrate of a first conductivity type. A lower cladding layer of the first conductivity type is provided on the semiconductor substrate. An active layer is provided on the lower cladding layer. An upper cladding layer of a second conductivity type opposite to the first conductivity type is provided on the active layer. A current blocking layer of the first conductivity type is buried in the upper cladding layer. The current blocking layer has a stripe-shaped groove serving as a current-injection region. The current-injection region is formed in a manner that it extends from an end face of a chip to the inside of the chip, and has a length shorter than that of the chip. The current blocking layer is made of a material having a band gap energy not greater than that of the active layer and a refractive index not smaller than that of the active layer so that light advancing in the active layer is absorbable.