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4H-SiC tips fabricated by etching 2 μm wide pillars at 1550 °C for 1 h. The inset shows that the tips are as narrow as 15 nm in diameter

LLNL researchers have developed an approach to form silicon carbide (and diamond) nanoneedles using plasma etching that create micro pillars followed by chemical etching of the pillars in forming gas containing hydrogen and nitrogen. Combining these two etching processes allow for fabrication of micro- and nanoneedles that are thinner and sharper than conventionally fabricated needles.

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LLNL energy grid protection device

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…

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JFET Device Structure

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…

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Tunneling Diode between two DSRDs

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.