Back to results
US 2003/0111658 A1Published application
Semiconductor light-emitting device
AssigneeSharp Kabushiki Kaisha
InventorsJunichi Nakamura, Kazuaki Sasaki
Life of this patent
Estimating the term…
Abstract
A semiconductor light-emitting device has a lower clad layer, an active layer, a p-type GaP layer and an upper clad layer, which are successively formed on an n-type GaAs substrate. The p-type GaP layer has a higher energy position by 0.10 eV than the upper clad layer in the conduction band, which makes it more difficult to let electrons escape from the active layer. This contributes to increase of the probability of radiative recombination between electrons and holes in the active layer, and thereby, luminance of the semiconductor light-emitting device is improved. The p-type GaP layer is effective in a semiconductor light-emitting device having a short wavelength in particular.
Claims56
A semiconductor light-emitting device comprising:
- a compound semiconductor substrate;
- a first-conductive-type clad layer formed on the compound semiconductor substrate;
- an active layer formed on the first-conductive-type clad layer and comprised of an AlGaInP-based semiconductor wherein light emitted from the active layer has a wavelength of not greater than 590 nm;
- a second-conductive-type clad layer formed on the active layer;
- and
- a semiconductor layer interposed between the active layer and the first-conductive-type clad layer or the second-conductive-type clad layer, wherein
- an energy position at a lower end of a conduction band of the semiconductor layer is 0.05 eV to 1.0 eV higher than an energy position at a lower end of a conduction band of the second-conductive-type clad layer in a band profile before formation of a junction between the active layer and the semiconductor layer, and a junction between the semiconductor layer and the first-conductive-type clad layer or the second-conductive-type clad layer.
4 more elements
A semiconductor light-emitting device comprising:
- a compound semiconductor substrate;
- a first-conductive-type clad layer formed on the compound semiconductor substrate;
- an active layer formed on the first-conductive-type clad layer and comprised of an AlGaInP-based semiconductor wherein light emitted from the active layer has a wavelength of not greater than 590 nm;
- a second-conductive-type clad layer formed on the active layer;
- and
- a semiconductor layer interposed between the active layer and the first-conductive-type clad layer or between the active layer and the second-conductive-type clad layer, wherein
- a highest energy position at a lower end of a conduction band of the semiconductor layer is 0.02 eV to 1.0 eV higher than an energy position at a lower end of a conduction band of the second-conductive-type clad layer.
4 more elements
A semiconductor light-emitting device comprising:
- a compound semiconductor substrate;
- a first-conductive-type clad layer formed on the compound semiconductor substrate;
- an active layer formed on the first-conductive-type clad layer and comprised of an AlGaInP-based semiconductor wherein light emitted from the active layer has a wavelength of not greater than 590 nm;
- a first second-conductive-type clad layer formed on the active layer;
- a second second-conductive-type clad layer formed on the first second-conductive-type clad layer;
- and
- at least one semiconductor layer interposed between the first second-conductive-type clad layer and the second second-conductive-type clad layer, wherein
- an energy position at a lower end of a conduction band of the semiconductor layer is 0.05 eV to 1.0 eV higher than an energy position at a lower end of a conduction band of the second second-conductive-type clad layer in a band profile before formation of a junction between the first second-conductive-type clad layer and the semiconductor layer and a junction between the semiconductor layer and second second-conductive-type clad layer.
5 more elements
A semiconductor light-emitting device comprising:
- a compound semiconductor substrate;
- a first-conductive-type clad layer formed on the a compound semiconductor substrate;
- an active layer formed on the first-conductive-type clad layer and comprised of an AlGaInP-based semiconductor wherein light emitted from the active layer has a wavelength of not greater than 590 nm;
- a first second-conductive-type clad layer formed on the active layer;
- a second second-conductive-type clad layer formed on the first second-conductive-type clad layer;
- and
- at least one semiconductor layer interposed between the first second-conductive-type clad layer and the second second-conductive-type clad layer, wherein
- an energy position at a lower end of a conduction band of the semiconductor layer is 0.02 eV to 1.0 eV higher than an energy position at a lower end of a conduction band of the second second-conductive-type clad layer.
5 more elements
A semiconductor light-emitting device comprising:
- a compound semiconductor substrate;
- a first first-conductive-type clad layer formed on the compound semiconductor substrate;
- a second first-conductive-type clad layer formed on the first first-conductive-type clad layer;
- at least one semiconductor layer interposed between the first first-conductive-type clad layer and the second first-conductive-type clad layer;
- an active layer formed on the second first-conductive-type clad layer and comprised of an AlGaInP-based semiconductor wherein light emitted from the active layer has a wavelength of not greater than 590 nm;
- and
- a second-conductive-type clad layer formed on the semiconductor layer, wherein
- an energy position at a lower end of a conduction band of the semiconductor layer is 0.05 eV to 1.0 eV higher than an energy position at a lower end of a conduction band of the first first-conductive-type clad layer in a band profile before formation of a junction between the first first-conductive-type clad layer and the semiconductor layer and a junction between the semiconductor layer and second first-conductive-type clad layer.
5 more elements
A semiconductor light-emitting device comprising:
- a compound semiconductor substrate;
- a first first-conductive-type clad layer formed on the compound semiconductor substrate;
- a second first-conductive-type clad layer formed on the first first-conductive-type clad layer;
- at least one semiconductor layer interposed between the first first-conductive-type clad layer and the second first-conductive-type clad layer;
- an active layer formed on the second first-conductive-type clad layer and comprised of an AlGaInP-based semiconductor wherein light emitted from the active layer has a wavelength of not greater than 590 nm;
- and
- a second-conductive-type clad layer formed on the semiconductor layer, wherein
- an energy position at a lower end of a conduction band of the semiconductor layer is 0.02 eV to 1.0 eV higher than an energy position at a lower end of a conduction band of the first first-conductive-type clad layer.
5 more elements
A semiconductor light-emitting device comprising:
- a compound semiconductor substrate;
- a first-conductive-type clad layer formed on the compound semiconductor substrate;
- an active layer formed on the first-conductive-type clad layer;
- and
- a second-conductive-type clad layer formed on the active layerm, wherein
- the active layer is an SQW active layer or an MQW active layer comprised of an AlGaInP-based semiconductor,
- the SQW layer or the MQW layer is comprised of a plurality of barrier layers and at least one well layer, and
- an energy position at a lower end of a conduction band from a vacuum level in part or all of the barrier layers is 0.05 eV to 1.0 eV higher than an energy position at a lower end of a conduction band from a vacuum level in (AlxGa1−x)yIn1−yP (x=0.7, y=0.51).
5 more elements
Dependencies are inferred from the claim text.