Ideally, the electronic components that route electricity through power supplies, inverters, and electric motors are cheap, efficient, and capable of handling high voltages. Judged in these terms, gallium oxide could be the best material yet, according to recent work by Flosfia, a startup in Kyoto.
That's because silicon—the incumbent material for making diodes and transistors for the power electronics market—is cheap but not very efficient. And although this weakness is addressed by devices made from silicon carbide and gallium nitride, both have had limited commercial success due to high prices. Flosfia's diodes are already performing more efficiently than those made from SiC and GaN.
The superiority of these gallium oxide devices stems from the material's approximately 5–electron-volt bandgap—way higher than that of gallium nitride (about 3.4 eV) or silicon carbide (about 3.3 eV). Bandgap is a measure of the energy required to kick an electron into a conducting state. A bigger bandgap enables a material to withstand a stronger electric field, making it possible to use a thinner device for a given voltage. That's a big deal because the thinner the device, the lower its resistance, and thus the more efficient it is.
Gallium oxide devices do not excel in all areas. Their Achilles' heel is poor thermal conductivity. "When you make a high-power device, you need to have a good thermal conductivity to extract the heat out of the device," explains Hong Lin, senior market and technology analyst at Yole Développement in Lyon, France.
(Score: 2) by khchung on Friday April 01 2016, @01:23AM
So it comes to that day of the year where all US websites become useless. Just like the Green site, I am just going to stop visiting for the day. Thanks for reminding me with the color scheme.
(Score: 1) by an Anonymous Coward on Friday April 01 2016, @02:00AM
It makes me wax all nostalgic over Geocities.
(Score: 2) by hemocyanin on Friday April 01 2016, @02:35AM
I was just thinking that myself, watching that green candy bar sweep across a field of twinkling stars.
(Score: 0) by Anonymous Coward on Friday April 01 2016, @01:24PM
Shut the fuck up and enjoy it you twat.
(Score: 0) by Anonymous Coward on Friday April 01 2016, @01:48AM
the thinner the device, the lower its resistance
That defies any Physics I ever learned.
The only way I can see a smaller dimension lowering resistance is making the drain-source channel SHORTER.
-- OriginalOwner_ [soylentnews.org]
(Score: 0) by Anonymous Coward on Friday April 01 2016, @02:08AM
It means "thinner" (i.e., shorter) junction. The summary also omits a key point on how they overcome thermal conductivity issue.
(Score: 2) by captain normal on Friday April 01 2016, @02:21AM
Even if it is April Fool's day, I'll bite. Electrical conductivity is dependent on surface area, not on thickness. Also if the material is a poor thermal conductor and holds heat instead of conducting it away, there's a problem as when a conductor heats up it's resistance raises.
"It is easier to fool someone than it is to convince them that they have been fooled" Mark Twain
(Score: 0) by Anonymous Coward on Friday April 01 2016, @07:26AM
conductivity is dependent on surface area, not on thickness
Well, at ridiculously high frequencies, there's the "skin effect" where the shape of the conductor can become the major determinant of the impedance.
Until you get to frequencies where that stuff is significant in the vector, resistance dominates and that is inversely proportional to the cross sectional area of the conductor.
-- OriginalOwner_ [soylentnews.org]
(Score: 2) by hemocyanin on Friday April 01 2016, @02:34AM
Mine eyes have seen their last.