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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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Diffuse discharge circuit breaker with latching switch

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…