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…
Keywords
- Show all (218)
- Additive Manufacturing (44)
- Instrumentation (39)
- Synthesis and Processing (19)
- Sensors (16)
- Diagnostics (12)
- Imaging Systems (9)
- Photoconductive Semiconductor Switches (PCSS) (9)
- 3D Printing (7)
- Materials for Energy Products (7)
- Carbon Utilization (6)
- Substrate Engraved Meta-Surface (SEMS) (6)
- Compact Space Telescopes (5)
- Data Science (5)
- Therapeutics (5)
- Diode Lasers (4)
- Laser Materials Processing (4)
- Material Design (4)
- Precision Optical Finishing (4)
- (-) Electric Grid (7)
- (-) Semiconductors (6)
LLNL researchers has developed designs to augment WBG/UWBG-based OALVs to improve their power handling capability under CW operational environments. These designs include:
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-…
The approach is to leverage the fact that a momentary “load” equal to the power transmission line impedance, (Z0), during the transient can suppress its propagation. Z(0) is typically a fixed impedance of several hundred ohms based on the geometry of most single wire transmission lines.
So, an isolated self-powered opticondistor (OTV) system may provide an ultrafast method of…
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.
LLNL’s novel approach to enable MVDC power systems to operate safely is to develop a wideband gap bulk optical semiconductor switch (WBG BOSS) circuit breaker. For higher power, efficiency and temperature operation, vanadium-doped silicon carbide (V-doped SiC) appears to be the most promising basis for WBG BOSS circuit breaker (other dopants like aluminum, boron and nitrogen may further…
LLNL researchers has developed an approach to mitigate HER on the ‘plating’ electrode, which uses a sub-device as a rebalancing cell to restore electrolyte properties, including pH, conductivity, and capacity across the main device of the flow battery. This sub-device, which may need to be powered externally, has three major physical components: (1) a cathode electrode, (2) an anode…
LLNL has developed a novel methodology for using commercially available automated sensors and actuators which can be deployed at scale in large appliances and plug-in EVs to provide as needed electric grid stabilization capabilities. The approach comprises of a population of voltage relays with a range of setpoints that would gradually reduce load as voltage falls. More severe voltage…
Improving the active material of the Zn anode is critical to improving the practicality of Zn-MnO2 battery technology. LLNL researchers have developed a new category of 3D structured Zn anode using a direct-ink writing (DIW) printing process to create innovative hierarchical architectures. The DIW ink, which is a gel-based mixture composed of zinc metal powder and organic binders, is…
To address many of the aforementioned challenges of manufacturing LIBs and SSBs, LLNL researchers have developed a number of inventions that offer proposed solutions for their components:
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…
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…
The Optical Transconductance Varistor (OTV, formerly Opticondistor) overcomes depletion region voltage limitations by optically exciting wide bandgap materials in a compact package. A 100μm thick crystal could have the capability approaching 40kV and would replace numerous equivalent junction devices. Thus, unlike present junction transistors or diodes, this wide bandgap device can be stacked…