UNIVERSITY of CALIFORNIA, SANTA BARBARA

Brief Description

A device with increased efficiency by combining shaped high refractive index elements with an (Al, Ga, In)N LED and shaped optical elements.

Background

Current methods of improving efficiency in nitride LED systems, such as the use of a thin nickel, gold, or zinc oxide layer growth to produce transparent electrodes, lack the surface feature shaping capabilities needed to optimize light extraction. Thus, there is a need for a device that overcomes this obstacle in order to create a more efficient LED.

Description

Researchers at the University of California, Santa Barbara have developed a device with increased efficiency by combining shaped high refractive index elements with an (Al, Ga, In)N LED and shaped optical elements. Through the increase in light transmittance and light extraction, subsequent device performance is improved. Specifically, a high refractive index ZnO layer is wafer bonded to a GaN LED. A cone is etched in the high refractive index ZnO layer and contacts are fabricated on the GaN LED. The ZnO/GaN hybrid LED is then placed within various configured lenses and covered by a phosphor layer for high efficiency light extraction. Due to these improvements, the device’s efficiency is significantly increased over typical LEDs. Also, the fabrication method may require fewer process steps due to the ease of electrode formation.

Advantages

• Optimized light extraction

• Highly efficient due to reduction of light absorption in the LED

• Reduced number of fabrication steps due to ease of electrode formation

Applications

• Solid-State Lighting

• Optoelectronic Applications

This technology is available for licensing. See below for a selection of the patents and patent applications related to this invention. Please inquire for full patent portfolio status.

Patent Status

Inventors

• DenBaars, Steven P.
• Nakamura, Shuji
• Speck, James S.

Other Information

Contact

Shaun R. Juncal / juncal@tia.ucsb.edu / tel: View Phone Number. Please reference Tech ID #21823.

ADDITIONAL TECHNOLOGIES BY THESE INVENTORS

• Fabrication Of High Quality P-Type GaN and Alloys by Preventing Hydrogen Incorporation
• Self-Assembled Nano-Cluster And Quantum Dot Lattices
• Reduced Dislocation Density of Non-Polar GaN Grown by Hydride Vapor Phase Epitaxy
• Growth of Planar, Non-Polar, A-Plane GaN by Hydride Vapor Phase Epitaxy
• Nonpolar (Al, B, In, Ga)N Quantum Well Design
• Electrically-Pumped Vertical-Cavity Surface-Emitting Laser (VCSEL)
• Improved Manufacturing of Semiconductor Lasers
• High Efficiency LED With Emitters Within Structured Materials
• Asymmetrically Cladded Laser Diode with Improved Performance
• Yellow-Emitting Phosphors for White LEDs
• Cleaved Facet Edge-Emitting Laser Diodes Grown on Semipolar GaN
• Etching Technique for the Fabrication of Thin (Al, In, Ga)N Layers
• Enhancing Growth of Semipolar (Al,In,Ga,B)N Films via MOCVD
• Device Structure for High Efficiency LED
• Selective Dry Etching of N-Face (Al, In, Ga)N Heterostructures
• High-Efficiency, White, Single, or Multi-Color LED by Photon Recycling
• GaN-Based Thermoelectric Device for Micro-Power Generation
• Mirrorless LED with High Luminous Efficiency
• Method for Producing GaN Substrates for Electronic and Optoelectronic Devices
• Hybrid Inorganic Light-Emitting Devices
• Growth of High-Quality, Thick, Non-Polar M-Plane GaN Films
• Method for Growing High-Quality Group III-Nitride Crystals
• Growth of Planar Semi-Polar Gallium Nitride
• Defect Reduction of Non-Polar and Semi-Polar III-Nitrides
• MOCVD Growth of Planar Non-Polar M-Plane Gallium Nitride
• Lateral Growth Method for Defect Reduction of Semipolar Nitride Films
• Low Temperature Deposition of Magnesium Doped Nitride Films
• Growth of Polyhedron-Shaped Gallium Nitride Bulk Crystals
• Long Wavelength Nonpolar and Semipolar Nitride-Based Laser Diodes
• Semipolar III-Nitride Laser Diodes with Etched Mirrors
• Fabrication of Optoelectronic Devices with Embedded Void-Gap Structures
• Method for Making a High Performance Vertical Cavity Surface Emitting Laser
• Use of Flux Method to Grow Seed Crystals for Ammonothermal Growth of Group-III Nitride Crystal Crystal Growth
• Method for Ammonothermal Growth of Highly Pure Group-III Nitrides
• LED Structure with Low Efficiency Droop for High-Current Applications
• Improved Manufacturing of Solid State Lasers via Patterning of Photonic Crystals
• Low Carrier Loss Device Structure for High Performance Green LEDs
• Control of Photoelectrochemical (PEC) Etching by Modification of the Local Electrochemical Potential of the Semiconductor Structure
• Phosphor-Free White Light Source
• Method for Wafer Bonding for Optoelectronic Applications
• Single or Multi-Color High Efficiency LED by Growth Over a Patterned Substrate
• High Efficiency LED with Optimized Photonic Crystal Extractor
• Wafer Bonding For Highly Efficient Nitride-Based LEDs
• Packaging Technique for the Fabrication of Polarized Light Emitting Diodes
• LED Device Structures with Minimized Light Re-Absorption
• High Efficiency and High Brightness LEDs for Various Lighting Applications
• Photoelectrochemical Etching for Laser Facets
• Enhancement Of Thermoelectric Properties Through Polarization Engineering
• Two dimensionally relaxed III-N buffer layers for LEDs
• Novel Layer Structure for Semipolar InGaN/GaN LEDs and Laser Diodes
• Efficient High-Power, Laser-Driven White Lighting Device
• GaN-based Green/Red Light-Emitting Diodes With Low Voltage
• Outdoor Street Light Fixture with Novel Laser Diode Light Source
• Improved LED Performance via Optimized Polarization Properties
• (In,Ga,Al)N Optoelectronic Devices with Thicker Active Layers for Improved Performance
• Controlling Contact Resistivity of Transparent Conductive Layers of Optoelectronic Devices

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• Light Absorbing Polymeric Material for Organic Photovoltaic Devices
• Zwitterionic Electron Injection Layers for Highly Efficient Polymer LEDs
• Photonic Structures for Efficient Light Extraction and Conversion in Multi-Color LEDs
• Growth of Group III-Nitride Crystals using Supercritical Ammonia and Nitrogen