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Can someone summarize the progress in synthetic diamond research for the past two decades? From mid-90s to early 00s I remember the diamond hype, from Neal Ste

by 19235982958329 8y ago

Can someone summarize the progress in synthetic diamond research for the past two decades? From mid-90s to early 00s I remember the diamond hype, from Neal Stephenson's The Diamond Age, to the practical refinement of making cost-effective synthetic gem quality diamonds, high-frequency heat-dissipating semiconductor wafers, and speculation of biocompatible nanotechnology such as respirocytes. What problems were encountered with scaling, energy efficiency, cost, and competitor materials? Are they still applicable technologies working their way through the R&D pipeline?

ridgeguy 8y ago
In general: Two pathways have led to economically viable synthetic gem diamonds. One is chemical vapor deposition (CVD), the other is high pressure, high temperature (HPHT) growth. The successful CVD makers use hydrogen+methane and high power microwaves (typically 915MHz, 30-60kW) to form plasmas that cause diamond to deposit and grow on small diamond seeds. IIa Technologies, Diamond Foundry are two of these. HPHT is an old technology, the first to unambiguously demonstrate diamond synthesis in the 1950s. It grows diamonds in metal solvents at high temperature and pressure (typically 1000°C at a million psi). It has come to be successful in gem diamond production due to better press design and use of modern process controls. The business challenge in gem diamond production isn't any aspect of the technology. It's the sales. De Beers has a hundred years of channels for whatever type of diamond they want to sell. Newcomers have to build their own channels, largely because the older ones are highly loyal to De Beers and won't handle goods from any other source. As the CEO of one of the most successful synthetic diamond producers recently told me, if their cost of production were zero, it would still be a major challenge to sell their gems.

ridgeguy 8y ago

In general: Two pathways have led to economically viable synthetic gem diamonds. One is chemical vapor deposition (CVD), the other is high pressure, high temperature (HPHT) growth. The successful CVD makers use hydrogen+methane and high power microwaves (typically 915MHz, 30-60kW) to form plasmas that cause diamond to deposit and grow on small diamond seeds. IIa Technologies, Diamond Foundry are two of these. HPHT is an old technology, the first to unambiguously demonstrate diamond synthesis in the 1950s. It grows diamonds in metal solvents at high temperature and pressure (typically 1000°C at a million psi). It has come to be successful in gem diamond production due to better press design and use of modern process controls. The business challenge in gem diamond production isn't any aspect of the technology. It's the sales. De Beers has a hundred years of channels for whatever type of diamond they want to sell. Newcomers have to build their own channels, largely because the older ones are highly loyal to De Beers and won't handle goods from any other source. As the CEO of one of the most successful synthetic diamond producers recently told me, if their cost of production were zero, it would still be a major challenge to sell their gems.