Semiconductor device
AssigneeSharp Kabushiki Kaisha
InventorStephen Peter Najda
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Abstract
An (Al,Ga,In)P semiconductor laser device has an optical region disposed between n-type and p-type cladding layers. An active region containing quantum well active layers and barrier layers disposed alternately with the quantum well layers is provided within the optical guiding region. Strained layers of InxGal−xP are used as the barrier layers. The active region is thus aluminium-free, and this reduces the oxygen impurity concentration in the active region thereby improving the performance and reliability of the laser. An aluminium-free spacer layer can be provided between one of the cladding layers and the quantum well active layer disposed closest to that cladding layer. The invention may be applied to other semiconductor devices, for example such as an LED.
Claims30
A semiconductor device having an aluminium-free active region, the active layer comprising one or more quantum well layers and one or more barrier layers, the quantum well layer(s) and the barrier layer(s) being disposed alternatively;
- wherein the or each barrier layer is a strained layer;
- the device further comprises a first cladding layer and an aluminium-free layer disposed between the first cladding layer and the quantum well layer closest to the first cladding layer, and the device is adapted to emit, in use, light having a wavelength in the range 630 to 680 nm.
A semiconductor device having an aluminium-free active region, the active layer comprising one or more quantum well layers and one or more barrier layers, the quantum well layer(s) and the barrier layer(s) being disposed alternately;
- wherein the or each barrier layer is a strained layer;
- and wherein the device emits, in use, light having a wavelength in the range 630 to 680 nm.
Dependencies are inferred from the claim text.