Sandia Corporation

Other

Mary H Crawford

Andrew A Allerman

Daniel F Feezell

Daniel D Koleske

Andrew Armstrong

Morteza Monavarian

Saadat Mishkat-Ul-Masabih

Andrew Aragon

Stephen R Lee

Martin F Schubert

Thomas Daniel Raymond

E Fred Schubert

Richard P Schneider, Jr

Jeffrey S Nelson

William J Alford

Jaehee Cho

Mary A Miller

Ahmed Noemaun

Di Zhu

A method comprises providing a substrate comprising an n-type Al/In/GaN semiconductor material. A surface of the substrate is dry-etched to form a trench therein and cause dry-etch damage to remain on the surface. The surface of the substrate is immersed in an electrolyte solution and illuminated with above bandgap light having a wavelength that generates electron-hole pairs in the n-type Al/In/GaN semiconductor material, thereby photoelectrochemically etching the surface to remove at least a portion of the dry-etch damage.

Removing or preventing dry etch-induced damage in Al/In/GaN films by photoelectrochemical etching

A p-type superlattice is used to laterally inject holes into an III-nitride multiple quantum well active layer, enabling efficient light extraction from the active area. Laterally-injected light-emitting diodes and laser diodes can enable brighter, more efficient devices that impact a wide range of wavelengths and applications. For UV wavelengths, applications include fluorescence-based biological sensing, epoxy curing, and water purification. For visible devices, applications include solid state lighting and projection systems.

Laterally injected light-emitting diode and laser diode

Tailored doping of barrier layers enables balancing of the radiative recombination among the multiple-quantum-wells in III-Nitride light-emitting diodes. This tailored doping enables more symmetric carrier transport and uniform carrier distribution which help to reduce electron leakage and thus reduce the efficiency droop in high-power III-Nitride LEDs. Mitigation of the efficiency droop in III-Nitride LEDs may enable the pervasive market penetration of solid-state-lighting technologies in high-power lighting and illumination.

High efficiency III-nitride light-emitting diodes

A denticulated Group III nitride structure that is useful for growing AlGaN to greater thicknesses without cracking and with a greatly reduced threading dislocation (TD) density.

Aluminum nitride transitional layer for reducing dislocation density and cracking of AlGaN epitaxial films

Aluminum nitride transitional layer for reducing dislocation density and cracking of AIGan epitaxial films

A visible light source device is described based on a light emitting diode and a nanocluster-based film. The light emitting diode utilizes a semiconductor quantum well structure between n-type and p-type semiconductor materials on the top surface a substrate such as sapphire. The nanocluster-based film is deposited on the bottom surface of the substrate and can be derived from a solution of MoS , MoSe , WS , and WSe particles of size greater than approximately 2 nm in diameter and less than approximately 15 nm in diameter, having an absorption wavelength greater than approximately 300 nm and less than approximately 650 nm.

Broadband visible light source based on AllnGaN light emitting diodes

A frequency-doubled semiconductor vertical-external-cavity surface-emitting laser (VECSEL) is disclosed for generating light at a wavelength in the range of 300-550 nanometers. The VECSEL includes a semiconductor multi-quantum-well active region that is electrically or optically pumped to generate lasing at a fundamental wavelength in the range of 600-1100 nanometers. An intracavity nonlinear frequency-doubling crystal then converts the fundamental lasing into a second-harmonic output beam. With optical pumping with 330 milliWatts from a semiconductor diode pump laser, about 5 milliWatts or more of blue light can be generated at 490 nm. The device has applications for high-density optical data storage and retrieval, laser printing, optical image projection, chemical-sensing, materials processing and optical metrology.

Frequency-doubled vertical-external-cavity surface-emitting laser

A visible semiconductor laser. The visible semiconductor laser includes an InAlGaP active region surrounded by one or more AlGaAs layers on each side, with carbon as the sole p-type dopant. Embodiments of the invention are provided as vertical-cavity surface-emitting lasers (VCSELs) and as edge-emitting lasers (EELs). One or more transition layers comprised of a substantially indium-free semiconductor alloy such as AlAsP, AlGaAsP, or the like may be provided between the InAlGaP active region and the AlGaAS DBR mirrors or confinement layers to improve carrier injection and device efficiency by reducing any band offsets. Visible VCSEL devices fabricated according to the invention with a one-wavelength-thick (1.lambda.) optical cavity operate continuous-wave (cw) with lasing output powers up to 8 mW, and a peak power conversion efficiency of up to 11%.

Visible-wavelength semiconductor lasers and arrays

Growing community of inventors

Tampa, FL, United States of America

Mary H Crawford