Lumileds Lighting U.s., LLC

Luxnet Corporation

Other

Hewlett-packard Company

Philips Lumileds Lighting Company LLC

Chihping Kuo

Werner K Goetz

R Scott Kern

Changhua Chen

Paul Scott Martin

Michael David Camras

Daniel Alexander Steigerwald

Ghulam Hasnain

Hao-chung Kuo

Gina L Christenson

Andrew Shuh-Huei Liao

Zhiqing Shi

Minh Ngoc Trieu

Robert M Fletcher

Timothy D Osentowski

Virginia M Robbins

Kuo-Hsin Huang

Jiann Yu

Xiaoping Chen, Legal Representative

P-type layers of a GaN based light-emitting device are optimized for formation of Ohmic contact with metal. In a first embodiment, a p-type GaN transition layer with a resistivity greater than or equal to about 7 &#x3a9; cm is formed between a p-type conductivity layer and a metal contact. In a second embodiment, the p-type transition layer is any III-V semiconductor. In a third embodiment, the p-type transition layer is a superlattice. In a fourth embodiment, a single p-type layer of varying composition and varying concentration of dopant is formed.

Formation of Ohmic contacts in III-nitride light emitting devices

P-type layers of a GaN based light-emitting device are optimized for formation of Ohmic contact with metal. In a first embodiment, a p-type GaN transition layer with a resistivity greater than or equal to about 7 &#x3a9;cm is formed between a p-type conductivity layer and a metal contact. In a second embodiment, the p-type transition layer is any III-V semiconductor. In a third embodiment, the p-type transition layer is a superlattice. In a fourth embodiment, a single p-type layer of varying composition and varying concentration of dopant is formed.

A current confinement element that can be used in constructing light-emitting devices. The current confinement element includes a top layer and an aperture-defining layer. The top layer includes a top semiconducting material of a first conductivity type that is transparent to light. The aperture-defining layer includes an aperture region and a confinement region. The aperture region includes an aperture semiconducting material of the first conductivity type that is transparent to light. The confinement region surrounds the aperture region and includes a material that has been doped to provide a high resistance to the flow of current. In one embodiment of the invention, the confinement region includes a semiconducting material of a second conductivity type.

Vertical-cavity surface emitting laser utilizing a reversed biased diode for improved current confinement

P-type layers of a GaN based light-emitting device are optimized for formation of Ohmic contact with metal. In a first embodiment, a p-type GaN transition layer with a resistivity greater than or equal to about 7 &OHgr;cm is formed between a p-type conductivity layer and a metal contact. In a second embodiment, the p-type transition layer is any III-V semiconductor. In a third embodiment, the p-type transition layer is a superlattice. In a fourth embodiment, a single p-type layer of varying composition and varying concentration of dopant is formed.

Formation of ohmic contacts in III-nitride light emitting devices

A laser diode that includes a light guiding structure that improves the light-output-versus-current curve by altering the multiple spatial modes of the laser diode. A laser diode according to the present invention includes a bottom mirror constructed on an electrically conducting material, an active region constructed from a first conductive spacer situated above the bottom mirror, a light emitting layer, and a second conductive spacer situated above the light emitting layer. The laser diode also includes a top mirror constructed from a plurality of mirror layers of a semiconducting material of a first conductivity type that are located above the second conductive spacer. The adjacent mirror layers have different indexes of refraction. One or more of the top mirror layers is altered to provide an aperture defining layer that includes an aperture region that alters the spatial modes of the device.

Vertical cavity surface emitting laser having improved light output function

A current confinement element that can be used in constructing light-emitting devices. The current confinement element includes a top layer and an aperture-defining layer. The top layer includes a top semiconducting material of a first conductivity type that is transparent to light. The aperture-defining layer includes an aperture region and a confinement region. The aperture region includes an aperture semiconducting material of the first conductivity type that is transparent to light. The confinement region surrounds the aperture region and includes a material that has been doped to provide a high resistance to the flow of current. The aperture-defining layer is constructed by implanting or diffusing elements into one or more of the mirror layers prior to depositing the remaining mirror layers on top of the aperture-defining layer.

Method for making a vertical-cavity surface emitting laser with improved current confinement

In the present invention, an interfacial layer is added to a light-emitting diode or laser diode structure to perform the role of strain engineering and impurity gettering. A layer of GaN or Al,In,Ga,N (0&lE;x&lE;1, 0&lE;y&lE;1) doped with Mg, Zn, Cd can be used for this layer. Alternatively, when using Al,In,Ga,N (x>0), the layer may be undoped. The interfacial layer is deposited directly on top of the buffer layer prior to the growth of the n-type (GaN:Si) layer and the remainder of the device structure. The thickness of the interface layer varies from 0.01-10.0 &mgr;m.

Method of strain engineering and impurity control in III-V nitride semiconductor films and optoelectronic devices

In the present invention, an interfacial layer is added to a light-emitting diode or laser diode structure to perform the role of strain engineering and impurity gettering. A layer of GaN or Al,In,Gal,N (0&lE;x&lE;1, 0&lE;y&lE;1) doped with Mg, Zn, Cd can be used for this layer. Alternatively, when using Al,In,Ga,N (x>0), the layer may be undoped. The interfacial layer is deposited directly on top of the buffer layer prior to the growth of the n-type (GaN:Si) layer and the remainder of the device structure. The thickness of the interfacial layer varies from 0.01-10.0 &mgr;m.

Strain engineered and impurity controlled III-V nitride semiconductor films and optoelectronic devices

A light emitting diode (LED) including a light generation region situated on a light-absorbing substrate also includes a thick transparent layer which ensures that an increased amount of light is emitted from the sides of the LED and only a minimum amount of light is absorbed by the substrate. The thickness of the transparent layer is determined as a function of its width and the critical angle at which light is internally reflected within the transparent layer. The thick transparent layer is located either above, below or both above and below the light generation region. The thick transparent layer may be made of materials and with fabrication processes different from the light generation region.

Light-emitting diode with a thick transparent layer

A light-emitting diode has a semiconductor substrate underlying active p-n junction layers of AlGaInP for emitting light. A transparent window layer of semiconductor different from AlGaInP overlies the active layers and has a lower electrical resistivity than the active layers and a bandgap greater than the bandgap of the active layers, for minimizing current crowding from a metal electrical contact over the transparent window layer. The active layers may be epitaxially grown on a temporary GaAs substrate. A layer of lattice mismatched GaP is then grown on the active layers with the GaP having a bandgap greater than the bandgap of the active layers so that it is transparent to light emitted by the LED. The GaAs temporary substrate is then selectively etched away so that the GaP acts as a transparent substrate. A transparent window layer may be epitaxially grown over the active layers on the face previously adjacent to the GaAs substrate.

Growing community of inventors

Milpitas, CA, United States of America

Chihping Kuo