New Solution For Your Transistor BBQ 191
servantsoldier writes "There's a new solution for the transistor heat problem: Make them out of charcoal... The AP is reporting that Japanese researchers, led by Daisuke Nakamura of Toyota Central R&D Laboratories Inc., have discovered a way to use silicon carbide instead of silicon in the creation of transistor wafers. The Japanese researchers discovered that they can build silicon carbide wafers by using a multiple-step process in which the crystals are grown in several stages. As a result, defects are minimized. Other benefits are decreased weight and a more rugged material. The researchers say that currently only a 3" wafer has been produced and that a marketable product is at least six years away."
Re:typical bad science journalism (Score:5, Informative)
But yeah, that article was pretty light on details.
Re:how hot? (Score:2, Informative)
http://www.grc.nasa.gov/WWW/RT1997/5000/5510neudec k2.htm [nasa.gov]
http://www.acreo.se/templates/Page____577.aspx [acreo.se]
I just asked Google [google.at]
Re:Finally... Heat can be put to good use (Score:1, Informative)
Re:Finally... Heat can be put to good use (Score:3, Informative)
I disagree. I've just upgraded an Athlon XP 1800+ system to an Athlon64 3500+.
The new box runs around 20 degrees C cooler than the old one at idle and under heavy load; both use the supplied retail AMD heatsinks. I'm not using "Cool 'n Quiet" on the '64; it might take a bit off the idle temperature, but I don't see the point.
Re:Wow (Score:4, Informative)
In the event that we find out that someone else already HAS "invented" this idea, it is usually NTT (Nippon Telephone and Telegraph) which has also registered the hell out of a shit load of trademarks that it doesn't use.
And, over here, there are a lot of people worried that we've really lost our tech edge against China and Taiwan. To a certain extent, I think they're right. China and Taiwan used to be copiers, not innovators. But then again, so was Japan half a century ago. Recently, China and Taiwan have started innovating too. It should have been obvious that they "could" innovate, about 18 years ago when the first fake Nintendo consoles from Taiwan were found. They say over 80% of the circuitry, including the CPU, was original, and not a copy. (Then again, a lot of the fake Apple IIe machines back then were pretty original too, sometimes with features that weren't available on the real thing!)
What does silicon carbide have to do with a BBQ? (Score:5, Informative)
Comparing this to charcol is like saying that Carbon Monoxide is the same thing as Oxygen because CO contains oxygen.
Jason
intended for extreme conditions (Score:1, Informative)
Devices built with the rugged material would not require cooling and other protections that add size, weight and cost to traditional silicon electronics in power systems, jet engines, rockets, wireless transmitters and other equipment exposed to harsh environments.
So you see, besides that it is nearly as hard as diamond and can survive the temperatures of re-entry into the Earth's atmosphere, they want use it to replace silicon electronics that are used in more stressful environments. Although I suppose that the over-clockers should rejoice.
All this silly stuff, but (Score:5, Informative)
There are also huge potential benefits for rad-hard communications satellites, where cooling is a major problem (radiation only.)
The BBC article (Score:3, Informative)
Cooler != less heat produced (Score:3, Informative)
It's possible all you've proved is that coolers are getting better quicker than processors are getting hotter...
Read the post again (Score:3, Informative)
Also, please note that the junction temperatures you quote are maxima. You will not get good life at high temperatures with silicon but, more importantly, the ability to handle pulses and voltage drops as junction temperature rises. I suggest you look at the SOAR curves for a few power devices to see what I mean.
As for the rest of your remarks, it's clear you are not a serious power electronics designer. No-one says the low level stages have to run that hot (though anyone who has listened to a good tube amp would probably argue that you are exaggerating the importance of shot noise). The big benefit of higher junction temperatures is that heatsinks, in particular, can be smaller, especially if the hot air is vented straight out of the casing. This makes the overall size of the equipment smaller.
Also, don't forget that power amplification is not synonymous with hi-fi. There are many applications for power audio devices (PA systems, for instance) that require considerable audio power but only moderate quality, and the applications for compact RF devices are continually expanding. For instance, one possible goal for a high power SiC device would be a replacement for the magnetrons of microwave ovens, possibly even creating a market for small solar or wind powered microwave ovens that would be useful both for backpackers and for 3rd world countries.
Re:Charcoal? Isn`t a bit hard to saw wafer? (Score:4, Informative)
It's going to be a little slower, as SiC is about twice as hard as silicon, but that's not going to slow it down that much. Diamond saws are also used to chop up boules of sapphire and ruby, which are of similar hardness to SiC (a little softer), and also diamond (harder), so it's no big techical problem.
Or, a laser. A nice big excimer laser would slice it neater than a diamond saw. With the improved surface texture after cutting, the decrease is polishing coupled with the increase in hardness might make it worth while. Probably not, though.
[0] I use my saw for cutting rocks for lapidary purposes, principly quatrz of various sorts.