Patent ID: 9373937
Filing Date: 2016-06-21
CPC Classification: H01S

Claim Text:
1. A semiconductor laser comprising a layer structure comprising layers arranged one on top of another with at least the following layer sequence, the semiconductor laser comprising: an n-doped cladding layer; a third waveguide layer overlying the n-doped cladding layer; an active zone overlying the third waveguide layer, wherein light generating structures are arranged in the active zone; a second waveguide layer overlying the active zone; a blocking layer overlying the second waveguide layer; a first waveguide layer overlying the blocking layer; and a p-doped cladding layer overlying the first waveguide layer; wherein the first, second and third waveguide layers comprise at least Al wherein the blocking layer has an Al concentration that is at least 2% greater than the Al concentration of the first waveguide layer; wherein the blocking layer has an increase in Al concentration from the first waveguide layer in a direction toward the second waveguide layer; and wherein the blocking layer has a double-side stepped graduation, such that at least part of the blocking layer has a greater width than the first waveguide layer.