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UIUC Researchers Create Light Emitting Transistor
thesilverbail writes "Researchers at the University of Illinois have demonstrated light emission from the base layer of a Bipolar Transistor. This discovery could be the beginning of an era in which photons are directed around a chip in much the same fashion as electrons have been maneuvered on conventional chips. It's reminiscent of the exciting days of the Miracle month November, 1947, when the transistor was first invented."
What this means is that someone has taken the same materials which emit light as part of a single-junction device (a diode) and have also made them do so as part of a bi-junction device. While this looks like it might be a good way to integrate light emission with the control circuitry, it's not going to do anything to make them easier to integrate into large devices (silicon works for this because its oxide, SiO2, is a pretty good insulator while gallium doesn't do anything so convenient).
I will admit that it's clever, and someone may find some unobvious way of turning it into a useful device (massively parallel optical interconnects?), but there's just no way that this is going to be slapped onto the next Intel or AMD die. It especially will not replace aluminum or copper interconnects between parts of one processor.
Time is Nature's way of keeping everything from happening at once... the bitch.
It's an extension of the idea of the Light emitting Diode but it doesn't mean we'll have optical computers any time soon. The transistor still runs on current, it only outputs light! That means it can not drive another LET which means fully optical based devices aren't possible.
What this DOES mean however, is smaller devices in the realm of electronic/optical interaction. The basic functionality of this transistor is similar to a small combination of transistors and diodes except that this does it in one device. The device is rather large but it'll probably shrink rather quickly as it's still in the early stages of development.
This one time I made some smoke emitting transistors.
Tim
Omnia vestra castrorum habetur nobis.
Sure, but assuming you've done something like I've done (try to switch several amps through a 2N2222 rated at .8 amps) isn't exactly considered "Solid State".
Among the years I've invented several new technologies in class:
The one-time self-deassembling capacitor. (put a high enough voltage on a elko to build one)
The flash diode. (build a bridge rectifier and replace one diode with a zenerdiode)
The automatic copper trace remover. (short a 7Ah lead accu through a trace on a circuit board. Capable of removing quite wide tracks)
Guess I should take a patent on those. They must have millions of possible uses.
This is great. It's not to do computations. Really, silicon is good and fast enough for that right now (of course it would be real cool if possible, but that won't work). However, couple this effect with phototransistors which already are in the domain of high frequency (at least theoretical results suggest so - 10 GHz here) and you end of with the dream of board engineers - forget wiring chips with metal. Interconnect them with fiber! Certainly with germanium it's gonna bit a bit difficult, but it's worth it: all you need to wire to chips is power, end of distance limit between chips, and forget problems of spilling something on the board! Even with current germanium version it'll work perfect for connectors between boards.
iThink iHate iMod
Since switching speed is also a function of the size of the device (capacitance), this transistor probably wouldn't produce any benefit over the LED version.
The article seems to be saying that they could get higher switching speeds out of this transistor, but we still have inefficiencies here: either the amplified output is used, or the optical output is used. Why would it be necessary to use both? And if the benefits come from not having to drive interconnects between the transistor and LED, we already have integrated transistor/led packages on the same substrate. It might be a better idea to make the emitter current the light emmiting part because then you'd be able to save on component costs.
I don't think it heralds in any type of light passed processing age. There is still the unresolved problem of creating a sensor that is sesitive to pick up a small amount of light, let alone making such a sensor small amd efficient. Untill that occurs, then this is just another advance that we probably can't use for what we think we can.
Things that would get my attention:
implemented in SiGe instead of III-V materials
bidirectional transduction in O->E not just O->E at usable efficiencies
demonstration of integration into "conventional" manufacturing processes
Otherwise, it's an interesting academic exercise that might lead to the above points, which is "A Good Thing".
I say we use this to make TVS with resolutions of ten trillion by ten trillion. then you can like... take a microscope to your tv and see the bacteria on the actors. I bet james earl jones has herpes.
-You're wasting your time. Alfador only likes me.
I invented a light-emitting resistor in a UIUC circuit design course over ten years ago. It only worked once, though, and it burned my fingers.
Debugging hardware could become simpler however. You could "see" (or have a computer watch) exactly what each transistor is doing. This could greatly enhance the ability to test real chips. Of course the transistors are usually buried under the metal layers, so I guess it depends on how bright the transistors are or if the designers are willing to leave (lots) of gaps in the metal layer for at least the "important" transistors.
Mark
As Nietsche famously said, "If you stare too long into the Abyss, 1d4 Tanar'ri of random type will attack you."