Re: Homemade SiC LED
klugesmith, Thu Aug 27 2009, 09:11PM

Very nice. Where'd you get the SiC?

Are you familiar with Ernest Glitch, fictional 19th century experimentalist? In a rambling 1861 letter to Michael Faraday, he talks about making crystalline "carbon silicide" in an electric arc furnace, then exploiting its property of cold galvanoluminescence to make what he called LED's. Story and illustration (near the bottom) at

Re: Homemade SiC LED
cduma, Thu Aug 27 2009, 09:56PM

That is really cool! What would I need to perform this experiment for my self?

Re: Homemade SiC LED
Conundrum, Fri Aug 28 2009, 12:17AM

i have some glowing SiC samples preset in low melt alloy, if they are useful. also have some fresh crystals and there should be a few emissive spots.

pm me if you'd like some. bearing in mind the crystal cost me £16 but i have at least 11 of the glowing ones...

EDIT: they are on ebay as well, includes suitable connectors and ultrafine copper wire for making catswhiskers.

I did wonder about using a calculator's conductive rubber strip as a contact, also could use a small piece of a dead LCD panel's ITO layer. The ideal material would be a sprung gold coated CuBe wire...

EDIT:- another more devious solution is to use conductive thread, as it nicely complies with the surface. Its also somewhat transparent and inherently limits the current so the crystal shouldn't fry.

EDIT 2:- a good source of flexible ITO is the plastic sheet from an old broken touch pad. The sort used in DS's work, as do mobile phones.
Cut a sliver of that, connect to one end's surface using conductive paint or alloy and "probe" the crystal with the other end but same surface.

Failing that, a reasonably strong electrolyte will work to some extent, as SiC doesen't dissolve encasing the crystal in wax/shellac except for the located glowing regions will do the trick.

Its amazing how bright it glows, in some cases almost as good as an early yellow LED.