LED from Silicon Carbide crystals

[wil3]

Hello. I am interested in making homemade LEDs in the manner described here:

http://www.popsci.com/diy/article/2010-02/gray-matter-light-mystery

Could this work with silicon carbide sandpaper instead of the crystal form? If so, would I want to go for a lower grit to improve the chances of isolating a single crystal, or should I favor a very fine grit so as to improve the chances of creating air gaps between adjacent crystals. I don't understand whether the luminescence requires an air gap, or whether is is simply the result of directly applying current to the crystals.

Thank you very much in advance

 

[jbsteele]

for any advice you can give.The instructions in the article you mentioned are specifically for creating LEDs from single crystal silicon. Silicon carbide is not a suitable material for this purpose because it does not possess the same optoelectronic properties as silicon. If you want to use silicon carbide, then you would need to look into other methods of making LEDs, such as using gallium nitride-based materials. It is not necessary to have an air gap between adjacent crystals in order to create luminescence; however, a very fine grit may help improve the chances of isolating a single crystal. Generally speaking, a lower grit will result in larger grains of material, while a higher grit will produce finer grains.