Watch Out SiC, Diamond Power Semiconductors Are Coming For You!

The vast majority of semiconductors products we use every day are primarily constructed on a silicon process, using wafers of pure silicon. But whilst the economics are known, and processes mature, there are still some weaknesses. Especially for power applications. gallium nitride (GaN) and silicon carbide (SiC) are materials that have seen an explosion in uses in the power space, driven especially by an increase in electric vehicle sales and other high-power/high-voltage systems such as solar arrays. But, SiC is expensive and very energy intensive. It looks like diamond substrates could become much more common if the work by Diamfab takes off.

Diamond, specifically thin films of synthetic diamond formed on a suitable substrate, exhibits many desirable properties, such as a vastly superior maximum electric field compared with silicon, and a thermal conductivity five times better than copper. Such properties give diamond structures a big power and voltage advantage over SiC, which is in turn a lot better the pure silicon. This also means that diamond-based transistors are more energy efficient, making them smaller and cheaper, as well as better performing. Without the high formation temperatures needed for SiC, diamond could well be their downfall, especially once you factor in the reduced environmental impact. There is even some talk about solid-state, high-voltage diamond insulator capacitors becoming possible. It certainly is an interesting time to be alive!

We do cover news about future semiconductors from time to time, like this piece about cubic boron arsenide. We’ve also seen diamond being used as a battery, albeit a very weak radiative one.

[via EETimes]

Homemade Silicon Carbide LED

Here’s an LED indicator which was made at home out of a Silicon Carbide (SiC) crystal (Internet Archive Mirror). The concept is simple, but a bit of trial and error goes into getting that tiny amber spot to light up.

The guesswork comes in finding the right piece of crystal. First [KOS] broke it into tiny pieces, then he started poking the chunks with electrified probes to see if he could get some light out of them. Once an active area was found he needed a base for the crystal. The image above shows the two nails which he used. This provides a large mounting area that also acts as a heat sink to make sure the LED won’t burn itself out. There’s a solder blob which he kept molten with his iron until the crystal could be pushed into place. That holds it securely as the pin which serves as the cathode is positioned.

The whole setup is soldered to some protoboard and is ready to use. This is the second time we remember seeing this technique used to fabricate LEDS. The first time was an accident.