Nitride semiconductor light-emitting device and method for producing the same
AssigneeSharp Kabushiki Kaisha
InventorsMayuko Fudeta, Satoshi Komada, Ryu Kaihara
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Abstract
A nitride semiconductor light-emitting device has a first conductive-type nitride semiconductor layer, a superlattice layer provided on the first conductive-type nitride semiconductor layer, an active layer provided on the superlattice layer, and a second conductive-type nitride semiconductor layer provided on the active layer. An average carrier concentration of the superlattice layer is higher than an average carrier concentration of the active layer.
Claims18
A nitride semiconductor light-emitting device comprising:
- a first conductive-type nitride semiconductor layer;
- a superlattice layer provided on said first conductive-type nitride semiconductor layer;
- an active layer provided on said superlattice layer;
- and
- a second conductive-type nitride semiconductor layer provided on said active layer, wherein
- an average carrier concentration of said superlattice layer is higher than an average carrier concentration of said active layer,
- said superlattice layer is formed of alternate lamination of a doped layer containing a first conductive-type impurity and an undoped layer not containing said first conductive-type impurity,
- thickness per one layer of said doped layer is greater than or equal to 1.5 nm and less than or equal to 15 nm,
- thickness per one layer of said undoped layer is greater than or equal to 0.5 nm and less than or equal to 5 nm,
- each of said doped layer and said undoped layer of the superlattice layer contains In, and
- said active layer generates light, and
- the average carrier concentration of said superlattice layer is greater than or equal to 1.2 and smaller than 5 times the average carrier concentration of said active layer.
A method for producing a nitride semiconductor light-emitting device comprising the steps of:
- growing a first conductive-type nitride semiconductor layer on a substrate;
- growing a superlattice layer on said first conductive-type nitride semiconductor layer;
- growing an active layer on said superlattice layer;
- and
- providing a second conductive-type nitride semiconductor layer on said active layer, wherein
- a growth rate of said superlattice layer is greater than or equal to a growth rate of a well layer which is a part of said active layer,
- the step of growing said superlattice layer includes the step of alternately laminating a doped layer containing a first conductive-type impurity and an undoped layer not containing said first conductive-type impurity and growing said superlattice layer having higher average carrier concentration than that of said active layer,
- thickness per one layer of said doped layer is greater than or equal to 1.5 nm and less than or equal to 15 nm,
- thickness per one layer of said undoped layer is greater than or equal to 0.5 nm and less than or equal to 5 nm,
- each of said doped layer and said undoped layer of the superlattice layer contains In, and said active layer generates light, and
- a growth rate of said undoped layer is greater than or equal to the growth rate of said well layer.
Dependencies are inferred from the claim text.