Sandia Corporation

National Technology & Engineering Solutions of Sandia, LLC

University of Florida Research Foundation, Incorporated

George T Wang

Qiming Li

J Randall Creighton

Jonathan J Wierer, Jr

Kevin S Jones

Arthur J Fischer

Ganapathi Subramanian Subramania

Igal Brener

Roozbeh Tabrizian

Jeffrey Y Tsao

Daniel D Koleske

Daniel Robert Ward

Evan Michael Anderson

Shashank Misra

Xiaoyin Xiao

Jeremy Benjamin Wright

Andrew David Baczewski

Aaron Michael Katzenmeyer

Keshab R Sapkota

Emily M Turner

Jeffrey T Figiel

In one aspect, the disclosure relates to a super high frequency (SHF) or extremely high frequency (EHF) bulk acoustic resonator that includes a nanostructure, wherein the nanostructure includes a substrate, a three-dimensional structure disposed on the substrate, wherein the three-dimensional structure includes a planar structure including at least one nanocomponent and a matrix material contacting the nanocomponent on at least one side, the matrix material including an SiGe alloy or Ge. The disclosed bulk acoustic resonator operates at frequencies of from about 100 MHz to about 100 GHz, is capable of self-amplification upon application of direct current or voltage, and has a Q factor amplification exceeding 1. Also disclosed are methods for amplification of mechanical resonance in the disclosed bulk acoustic resonators and devices incorporating the bulk acoustic resonators.

Self-amplified resonators with embedded piezoresistive elements for high performance, ultra-low SWaP microwave and millimeter-wave applications

In a method of atomic precision advanced manufacturing (APAM), an atomic or molecular resist layer on a substrate surface is selectively depassivated by locally exciting the substrate surface with an optical beam effective to eject adsorbed atoms or molecules from the substrate surface. The substrate surface is further processed by exposing it to a precursor gas, decomposing the precursor gas to release a dopant, and incorporating the dopant into the substrate surface.

Photolithography of atomic layer resist

A layered heterostructure, comprising alternating layers of different semiconductors, wherein one of the atom species of one of the semiconductors has a faster diffusion rate along an oxidizing interface than an atom species of the other semiconductor at an oxidizing temperature, can be used to fabricate embedded nanostructures with arbitrary shape. The result of the oxidation will be an embedded nanostructure comprising the semiconductor having slower diffusing atom species surrounded by the semiconductor having the higher diffusing atom species. The method enables the fabrication of low- and multi-dimensional quantum-scale embedded nanostructures, such as quantum dots (QDs), toroids, and ellipsoids.

Method for fabricating embedded nanostructures with arbitrary shape

Quantum-size-controlled photoelectrochemical (QSC-PEC) etching provides a new route to the precision fabrication of epitaxial semiconductor nanostructures in the sub-10-nm size regime. For example, quantum dots (QDs) can be QSC-PEC-etched from epitaxial InGaN thin films using narrowband laser photoexcitation, and the QD sizes (and hence bandgaps and photoluminescence wavelengths) are determined by the photoexcitation wavelength.

Quantum-size-controlled photoelectrochemical etching of semiconductor nanostructures

A multicolor photonic crystal laser array comprises pixels of monolithically grown gain sections each with a different emission center wavelength. As an example, two-dimensional surface-emitting photonic crystal lasers comprising broad gain-bandwidth III-nitride multiple quantum well axial heterostructures were fabricated using a novel top-down nanowire fabrication method. Single-mode lasing was obtained in the blue-violet spectral region with 60 nm of tuning (or 16% of the nominal center wavelength) that was determined purely by the photonic crystal geometry. This approach can be extended to cover the entire visible spectrum.

Multicolor photonic crystal laser array

A method for forming a surface-textured single-crystal film layer by growing the film atop a layer of microparticles on a substrate and subsequently selectively etching away the microparticles to release the surface-textured single-crystal film layer from the substrate. This method is applicable to a very wide variety of substrates and films. In some embodiments, the film is an epitaxial film that has been grown in crystallographic alignment with respect to a crystalline substrate.

Method of fabricating low-dislocation-density epitaxially-grown films with textured surfaces

A top-down method of fabricating vertically aligned Group III-V micro- and nanowires uses a two-step etch process that adds a selective anisotropic wet etch after an initial plasma etch to remove the dry etch damage while enabling micro/nanowires with straight and smooth faceted sidewalls and controllable diameters independent of pitch. The method enables the fabrication of nanowire lasers, LEDs, and solar cells.

Method of fabricating vertically aligned group III-V nanowires

A temperature stable (color and efficiency) III-nitride based amber (585 nm) light-emitting diode is based on a novel hybrid nanowire-planar structure. The arrays of GaN nanowires enable radial InGaN/GaN quantum well LED structures with high indium content and high material quality. The high efficiency and temperature stable direct yellow and red phosphor-free emitters enable high efficiency white LEDs based on the RGYB color-mixing approach.

Amber light-emitting diode comprising a group III-nitride nanowire active region

Group III-nitride epilayers can be grown directly on copper substrates using intermediate passivation layers. For example, single crystalline c-plane GaN can be grown on Cu (110) substrates with MOCVD. The growth relies on a low temperature AlN passivation layer to isolate any alloying reaction between Ga and Cu.

Method to grow group III-nitrides on copper using passivation layers

A volume-scalable, high-brightness, electrically driven visible light source comprises a three-dimensional photonic crystal (3DPC) comprising one or more direct bandgap semiconductors. The improved light emission performance of the invention is achieved based on the enhancement of radiative emission of light emitters placed inside a 3DPC due to the strong modification of the photonic density-of-states engendered by the 3DPC.

Volume-scalable high-brightness three-dimensional visible light source

A method for growing low-dislocation-density material atop a layer of the material with an initially higher dislocation density using a monolayer of spheroidal particles to bend and redirect or directly block vertically propagating threading dislocations, thereby enabling growth and coalescence to form a very-low-dislocation-density surface of the material, and the structures made by this method.

Low-dislocation-density epitatial layers grown by defect filtering by self-assembled layers of spheres

A method for forming vertically oriented, crystallographically aligned nanowires (nanocolumns) using monolayer or submonolayer quantities of metal atoms to form uniformly sized metal islands that serve as catalysts for MOCVD growth of Group III nitride nanowires.

Highly aligned vertical GaN nanowires using submonolayer metal catalysts

A method for growing high quality, nonpolar Group III nitrides using lateral growth from Group III nitride nanowires. The method of nanowire-templated lateral epitaxial growth (NTLEG) employs crystallographically aligned, substantially vertical Group III nitride nanowire arrays grown by metal-catalyzed metal-organic chemical vapor deposition (MOCVD) as templates for the lateral growth and coalescence of virtually crack-free Group III nitride films. This method requires no patterning or separate nitride growth step.

Nanowire-templated lateral epitaxial growth of non-polar group III nitrides

A method for improving Mg doping of Group III-N materials grown by MOCVD preventing condensation in the gas phase or on reactor surfaces of adducts of magnesocene and ammonia by suitably heating reactor surfaces between the location of mixing of the magnesocene and ammonia reactants and the Group III-nitride surface whereon growth is to occur.

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Albuquerque, NM, United States of America

George T Wang