Back to results
US 6,618,413 B2Granted
Graded semiconductor layers for reducing threshold voltage for a nitride-based laser diode structure
AssigneeXerox Corporation
InventorsDavid P. Bour, Michael A. Kneissl
Life of this patent
Estimating the term…
Abstract
Graded semiconductor layers between GaN and AlGaN layers in a nitride based semiconductor laser structure reduce the threshold voltage of the laser structure by reducing the electric potential barrier at the interface between the GaN and AlGaN layers. The graded layers can be step graded, continuous graded or digital graded.
Claims10
A semiconductor laser structure comprising:
- a substrate;
- a plurality of III-V nitride semiconductor layers formed on said substrate, at least one of said plurality of III-V nitride semiconductor layers forms an active region, wherein a sufficient voltage is applied to said plurality of III-V nitride semiconductor layers to inject electron and holes into said active region to cause lasing from said semiconductor laser structure, and
- at least one of said plurality of III-V nitride semiconductor layers being an AlxGa1−xN layer, at least one of said plurality of III-V nitride semiconductor layers being an AlyGa1−yN layer, where 0<=x<y<=1, at least one graded semiconductor layer between said an AlxGa1−xN layer and said AlyGa1−yN layer, said at least one graded semiconductor layer having an aluminum content less than said AlyGa1−yN layer but more than said an AlxGa1−xN layer, wherein said at least one graded semiconductor layer reduces the electrical potential barrier between said an AlxGa1−xN layer and said AlyGa1−yN layer which reduces the threshold voltage necessary to cause lasing from said semiconductor laser structure.
Dependencies are inferred from the claim text.