This LLNL invention is a wide bandgap (WBG) or ultra-wide bandgap (UWBG) material comprising a PCSS that is modified, either chemically through alloying and/or mechanically through strain fields, in order to tune the energetic positions of the valence and/or conduction bands and the associated optical transition energies that create and quench the PCSS responsivity.

A thyristor will stay conducting until the current through the device is zero (“current zero”) or perhaps slightly negative.  LLNL’s approach is to use the opticondistor (“OTV”) to force this current zero in order to force the device into an “off” state.  By combining a light-activated thyristor with an OTV, a noise-immune, high efficiency, high-power switching device can be…

The researchers’ approach leverages the concept that dopants have high diffusivities in Ga2O3; the key lies in the selection of the appropriate dopant.  This LLNL invention describes two device types that employ this design:

Design and construction of a photoconductive switch requires a diamond photoconductor illuminated by light of a certain excitation wavelength. 

Characteristics of the LLNL-developed switch are as follows:

LLNL researchers have invented an ultrafast PCSS to drive a high-power laser diode with arbitrary pulse widths.  These devices operate by supplying a high voltage (>10 kV) to one side of the switch.  A short pulse of light illuminates the semiconductor, instantly turning it from highly resistive to highly conductive. Ultrawide bandgap (UWBG) semiconductors are used to achieve sub-…

LLNL’s novel approach is to use diamond substrates with the desired donor (nitrogen) and acceptor (boron) impurities.   In order to optically activate these deep impurities, the invention requires at least one externally or internally integrated light source.  The initial exposure to light can set up the desired conduction current, after which the light source could be turned…

Instead of producing individual DSRDs and bonding them, Tunnel DSRD's entire stack structure is grown epitaxially on a n- or p-type silicon wafer, resulting in a novel, “monolithic” stacked DSRD.  A tunnel diode is essentially a diode with very highly doped p and n regions such that the reverse breakdown voltage is 200 meV or lower. 

U.S. Patent No. 11,555,965 describes LLNL’s invention of “Illumination Frustums” for photoconductive switches to capture and “frustrate” the light from leaving the frustum.  LLNL researcher’s latest novel invention, “Twister Oven”, achieves this by encouraging laser light absorption in a photo conductor material.  Light enters the oven twisting and reflecting, making near normal…

For cooling a high power device, the novel approach is to use a thermoelectric cooler (TEC)-based embedded substrate with proper selection of the TEC material as an active cooler.  The packaging configuration of TEC allows cooling the entire die without the use of a fluid.  The process is compatible with the thin film TEC material.  Standard semiconductor processes can be used…

LLNL researchers faced this challenge by bridging the gap between VEDs and solid-state electronics (SSE).  Their approach was to create a hybrid vacuum microelectronic device (VMD) architecture that combines the properties of vacuum as the electronic medium and the compact form factor and manufacturing scalability of semiconductor microelectronic chips.

For this method, a Silicon on Insulator (SOI) wafer is used to tailor etch rates and thickness in initial steps of the process.  The simple three step process approach is comprised of grayscale lithography, deep reactive-ion etch (DRIE) and liftoff of the SOI wafer.  The liftoff process is used to dissolve the insulating layer, thus separating sections of the wafer as individual…

The approach is to use Charge Balance Layers (CBLs) to create a superjunction device in wide bandgap materials.  These CBLs enable the device to effectively spread the electric field over 2- or 3-dimensions within a semiconductor voltage sustaining layer instead of 1-dimension, thereby increasing the maximum voltage a device is capable of withstanding.  The challenge of using CBLs is…

Design and construction of a photoconductive switch requires a diamond photoconductor illuminated by light of a certain excitation wavelength.  The diamond material is specifically doped with substitutional nitrogen, which act as a source of electrons.  The device architecture allows maximum light entering the aperture.  The top and bottom electrodes are made of ultra wide band…

The approach is to use a custom-designed frustrum and attach it to the optical fiber that connects to the PCSS.  Light from the fiber enters the frustrum, spreads out, and enters the PCSS.  Any unabsorbed light re-enters the frustrum and, because of its geometry, reflects back into the PCSS itself with only a negligible fraction escaping from the fiber.  The shape of the novel…

Commercial fiber optic cables are the current standard for carrying optical signals in industries like communications or medical devices. However, the fibers are made of glass, which do not have favorable characteristics for applications that require flexibility and re-routing, e.g. typically brittle, limited selection of materials, dimension constraints.

LLNL researchers have developed a high-volume, low-cost diagnostic test that is easy to use and provides results in under an hour. The testing platform will provide emergency responders and other medical professionals with the ability to screen individuals using oral and nasal samples, and obtain results in approximately 30 minutes. This point-of-care testing approach will enable rapid triage…

LLNL researchers have developed a portable device which analyzes one or multiple types of body fluids or gases to test for one or more medical conditions. A bodily fluid (such as blood, perspiration, saliva, breath, or urine) is put into a condenser surface and is then separated into both a primarily gas fluid component and a second one that is primarily liquid. These two samples from the same…

LLNL scientists have developed a method to ensure the accuracy of that tomographic image by applying adaptive optics (AO) to OCT in a single instrument (AO-OCT). AO stabilizes the image being captured by the OCT device by utilizing a Hartmann-Shack wavefront sensor and a deformable mirror, a type of mirror designed to compensate for detected waveform abnormalities (such as ones caused by a…

LLNL scientists have developed a battery-powered device which is low-cost and multi-chambered for the extraction and amplification of nucleic acids from environmental, clinical, and laboratory samples via loop-mediated isothermal amplification (LAMP). This platform identifies pathogenic bacteria and assists in determining the optimal treatment plan. A multi-chamber amplification cartridge in…

LNLL scientists have invented a method for multiplexed detection of PCR amplified products which can be completed in a single step. Highly validated species-specific primer sets are used to simultaneously amplify multiple diagnostic regions unique to each individual pathogen. Resolution of the mix of amplified products is achieved by PCR product hybridization to corresponding probe sequences,…

LLNL scientists have created a standalone pathogen identifier that can be placed in public settings, such as in stores or on street corners. Not unlike an ATM in physical size, this kiosk will accept biological samples from an individual for multiplexed analysis. The sample collection process will be sufficiently simple such that anyone could begin the diagnostic process after making the…

This LLNL-developed invention is multiplexed and utilizes the Luminex bead-based liquid array, which contains 100 different unique beads. Oligonucleotide probes with sequences complementary to the target sequences are covalently coupled to these unique beads. These capture beads are mixed with viral samples obtained from the patient via cheek swabbing or a throat wash and subjected to PCR in a…

LLNL scientists have developed a high-confidence, real-time multiplexed reverse transcriptase PCR (RT-PCR) rule-out assay for foot and mouth disease virus (FMDV). It utilizes RT-PCR to amplify both DNA and RNA viruses in a single assay to detect FMDV as well as rule out other viruses that cause symptoms in livestock indistinguishable from those caused by FMDV, such as Bovine Herpes Virus-1 (…

LLNL researchers have invented a system for identifying all known and unknown pathogenic or non-pathogenic organisms in a sample. This invention takes a complex sample and generates droplets from it. The droplets consist of sub-nanoliter volume reactors which contain the organism sized particles. A lysis device lyses the organisms and releases the nucleic acids. An amplifier then magnifies the…

LLNL researchers have developed a method to quickly and accurately identify the family of a virus infecting a vertebrate via PCR. Universal primer sets consisting of short nucleic acid strands of 7 to 30 base pairs in length were created to amplify target sequences of viral DNA or RNA. These primers can amplify certain identifying sequences of all viral genomes sequenced to date as well as…

Using various excitation wavelengths, a hyperspectral microscope takes advantage of autofluorescence and polarized light scattering from cellular components to obtain composite images that highlight their presence. The light collection efficiency is maximized to achieve image acquisition times and rates suitable for in vivo applications.