Many things about diamonds seem eternal, including the many engineering problems related to making them work as a silicon replacement in semiconductor technology. Yet much like a diamond exposed to a stream of oxygen-rich air and a roughly 750°C heat source, time will eventually erase all of them. As detailed in a recent [Asianometry] video, over the decades the challenges with creating diamond wafers and finding the right way to dope pure diamond have been slowly solved, even if some challenges still remain today.
Diamond is basically the exact opposite as silicon when it comes to suitability as a semiconductor material, with a large bandgap (5.5 eV vs the 1.2 of silicon), and excellent thermal conductivity characteristics. This means that diamond transistors are very reliable, albeit harder to switch, and heat produced during switching is rapidly carried away instead of risking a meltdown as with silicon semiconductors.
Unlike silicon, however, diamond is much harder to turn into wafers as you cannot simply melt graphite and draw perfectly crystallized diamond out of said molten puddle. The journey of getting to the state-of-the art soon-to-be-4″ wafers grown on iridium alongside the current mosaic method is a good indication of the complete pain in the neck that just this challenge already is.
Continue reading “Why Diamond Transistors Are So Hard To Make”







