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Japan Developing Diamond-based Semiconductors
s spencer and others wrote in with submissions about Japan funding the development of diamond-based semiconductors to replace silicon chips. The main advantages of diamond include heat resistance and higher electrical resistance.
Diamond based semiconductors? Joy, we're returning to the days of the overly expensive CPU...
Isn't that a bad thing? It would increase power requirements, create heat, etc. Even if a diamond chip could stand that, not everything else in the box can - not to mention being a problem for laptop batteries.
As I recall, one of the ways to utterly destroy a diamond is to run an excess amount of current through it. So, if you try to overclock your diamond chip, could you vaporize it? What about current overloads caused by over heating or bad power supply? Could be interesting.
In the wild there are no dumb lions tigers or bears. Only humanity subsidizes the continued existence of the stupid.
I saw a show on PBS about diamonds one time. It turns out that they are relatively inexpensive, but the major diamond producers will deliberately limit quantity produced to keep the price up. Also, what kind of diamonds are they using. Industrial diamonds are relatively cheep, as any one who has a nice set of diamond files will tell you.
When I was at Auburn, we had Star Wars funding to look into this. We had created a diode that switched at 2000 celcius.
The idea was to have IC circuits right inside the rocket engines.
heat tolerance is important as the power dissipated is impressive with today's chips. Due to diamond's rather large bandgap, heat tolerance is a better than Si. Resistance is also useful. I'd imagine creating a MOSFET with a leaky gate is problematic. Part of the reason that BJTs dominated in the early days of the semiconductor industry is the lack of a suitable substance as an insulator between the gate and the channel. I'm thinking the researchers are referring to diamond's natural ability in undoped form to resist current flow, so that's one less obstacle to overcome.
Keep in mind that this article was written in 1982. It talks about prices dropping from $60,000 per carat to $30,000 a carat. The colapse it predicts happened in the early '90s, and prices of "perfect" diamonds are now quoted around $5,000 per carat, and can be had for slightly over $1,500 per carat without much trouble. The article also talks about resale values of diamonds being 40% of their retail value. Today, diamonds 1 carat and smaller are essentially worthless. Large retail jewlery chains are still maintaining a significant markup, but that is steadily decreasing now that the public has greater access to wholesale diamonds.
.25 carat diamonds in a custom setting she designed. $900) I saw another guy buy a 2.9 carat diamond engagement ring for $3500. It wasn't flawless, but it was an excelent stone, and impractically large.
If she has to have a diamond (even after reading that article), do a little research and buy a loose stone from a wholesale vendor. It's not hard to find one, and you can get a local jewler to make you a very nice setting for $100-300. For two months salary these days, she can have a ring that will give her a workout. When I purchased my fiancee's ring (a 2.72 carat saphire with two