摘要:
A low optical loss and high efficiency grating is placed within a broad-area high-power laser diode or single spatial mode laser diode to narrow the spectral width and stabilize the emission wavelength. Several embodiments of grating configurations are presented, together with the measured results of a reduction to practice of a particular embodiment.
摘要:
In one embodiment, an AlInGaP LED includes a bottom n-type layer, an active layer, a top p-type layer, and a thick n-type GaP layer over the top p-type layer. The thick n-type GaP layer is then subjected to an electrochemical etch process that causes the n-type GaP layer to become porous and light-diffusing. Electrical contact is made to the p-GaP layer under the porous n-GaP layer by providing metal-filled vias through the porous layer, or electrical contact is made through non-porous regions of the GaP layer between porous regions. The LED chip may be mounted on a submount with the porous n-GaP layer facing the submount surface. The pores and metal layer reflect and diffuse the light, which greatly increases the light output of the LED. Other embodiments of the LED structure are described.
摘要:
A low optical loss and high efficiency grating is placed within a broad-area high-power laser diode or single spatial mode laser diode to narrow the spectral width and stabilize the emission wavelength. Several embodiments of grating configurations are presented, together with the measured results of a reduction to practice of a particular embodiment.
摘要:
A light emitting device includes a semiconductor structure having a light emitting layer disposed between an n-type region and a p-type region. A porous region is disposed between the light emitting layer and a contact electrically connected to one of the n-type region and the p-type region. The porous region scatters light away from the absorbing contact, which may improve light extraction from the device. In some embodiments the porous region is an n-type semiconductor material such as GaN or GaP.
摘要:
A light emitting device includes a semiconductor structure having a light emitting layer disposed between an n-type region and a p-type region. A porous region is disposed between the light emitting layer and a contact electrically connected to one of the n-type region and the p-type region. The porous region scatters light away from the absorbing contact, which may improve light extraction from the device. In some embodiments the porous region is an n-type semiconductor material such as GaN or GaP.
摘要:
In one embodiment, an AlInGaP LED includes a bottom n-type layer, an active layer, a top p-type layer, and a thick n-type GaP layer over the top p-type layer. The thick n-type GaP layer is then subjected to an electrochemical etch process that causes the n-type GaP layer to become porous and light-diffusing. Electrical contact is made to the p-GaP layer under the porous n-GaP layer by providing metal-filled vias through the porous layer, or electrical contact is made through non-porous regions of the GaP layer between porous regions. The LED chip may be mounted on a submount with the porous n-GaP layer facing the submount surface. The pores and metal layer reflect and diffuse the light, which greatly increases the light output of the LED. Other embodiments of the LED structure are described.
摘要:
In some embodiments of the invention, a transparent substrate AlInGaP device includes an etch stop layer that may be less absorbing than a conventional etch stop layer. In some embodiments of the invention, a transparent substrate AlInGaP device includes a bonded interface that may be configured to give a lower forward voltage than a conventional bonded interface. Reducing the absorption and/or the forward voltage in a device may improve the efficiency of the device.
摘要:
A buried heterostructure (BH) laser source with a narrow active region is disclosed for use in close proximity with optically-addressed data storage media for read/write functionality in a relatively high data density format. The BH laser source is formed on a pregrooved or prepatterned substrate to form mesas upon which epitaxial layers are formed to form laser source active regions that have small emission apertures at the laser source facet output. Selective removal of semiconductor cladding material and replacement of this material with lower refractive index materials provides a way of obtaining further mode size-reduction at the output facet of the laser source. Each mesa has a top surface and adjacent sidewalls such that in the growth of the epitaxial layers above the active region doped with a first conductivity type, the above active region epitaxial layers depositing on the top surface deposit as a first conductivity type and depositing on said sidewalls deposit as a second conductivity type. This growth construction provides for a naturally formed p-n junction at the laser source active region and eliminates the need to perform a subsequent diffusion process to form such a junction. The optical cavities of the laser sources may be tapered so that die cleaving a predetermined point along the length of the optical cavity will provide the desired emission aperture size at the laser source output facet.
摘要:
Optical semiconductor devices with integrated diffraction gratings with higher quality are realized through the use of Al-free grating layers. AlGaAs/GaAs regime optical semiconductor devices, such as laser diodes or optical filters, conventionally utilize an AlGaAs grating layer that has a strong affinity for oxidation. Instead of a Al-containing layer, a quantenary, InGaAsP grating layer is utilized, lattice matched to the underlying AlGaAs/GaAs structure, substantially eliminating any problem of oxide contamination. Also, an Al-free, ternary InGaP grating layer is utilized in the InGaP/InGaAsP/GaAs material regime. The quantum well active region of these devices may also be modified to extend the gain bandwidth of operation of these devices to insure continued operation over a wider temperature range with the wavelength peak of the grating in that the wavelength peak of the grating more assuredly remains within the wavelength operating range of the device.