Surface-emitting laser and image forming apparatus using the same
AssigneeCanon Kabushiki Kaisha
InventorsYasuhisa Inao, Mitsuhiro Ikuta, Tetsuya Takeuchi
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Abstract
This invention provides a surface-emitting laser that can prevent delamination at the interface of a selective oxidation layer and a spacer layer, while suppressing any rise of voltage, to improve the reliability of operation.
Claims4
A surface-emitting laser comprising:
- an n-type semiconductor Bragg reflector arranged on a substrate:
- an active layer including AlGaInP formed on the n-type semiconductor Bragg reflector;
- a p-type spacer layer including AlInP formed on the active layer;
- a selective oxidation layer including AlzGa1-zAs formed on the p-type spacer layer;
- an p-type semiconductor Bragg reflector including AlGaAs formed on the selective oxidation layer;
- a first intermediate layer including AlxGa1-xAs arranged between the selective oxidation layer and the p-type spacer layer so as to adjoin the selective oxidation layer;
- a second intermediate layer including AlyGa1-yAs arranged between the selective oxidation layer and the p-type spacer layer so as to adjoin the first intermediate layer;
- and
- a third intermediate layer including AlGaInP arranged between the selective oxidation layer and the p-type spacer layer so as to adjoin the second intermediate layer,
- wherein the z, y, x of the above material satisfy the relationship of z>y>x.
A surface-emitting laser comprising an n-type semiconductor Bragg reflector, a p-type semiconductor Bragg reflector, and an active layer arranged between the reflectors, the reflectors and the active layer being laminated on a substrate, the p-type semiconductor Bragg reflector being arranged on the active layer through a p-type spacer layer and a selective oxidation layer, a current confinement structure being formed by oxidizing the selective oxidation layer, comprising:
- a first intermediate layer arranged so as to adjoin the selective oxidation layer and included a material free from progress of oxidation when oxidizing the selective oxidation layer;
- a second intermediate layer arranged so as to adjoin the first intermediate layer to adjust a difference between band gap values of the p-type spacer layer and the first intermediate layer;
- and
- a third intermediate layer arranged so as to adjoin the second intermediate layer to adjust a difference between band gap values of the p-type spacer layer and the first intermediate layer,
- wherein the first intermediate layer, the second intermediate layer, and the third intermediate layer are arranged between the selective oxidation layer and the p-type spacer layer.
Dependencies are inferred from the claim text.