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Experimental Transistor Breaks 600 Gigahertz
neutron_p writes "The goal of a terahertz transistor for high-speed computing and communications applications could now be within reach. A new type of transistor structure, invented by scientists at the University of Illinois, has broken the 600 gigahertz speed barrier.
A new type of transistor - built from indium phosphide and indium gallium arsenide - is designed with a compositionally graded collector, base and emitter to reduce transit time and improve current density. With their pseudomorphic heterojunction bipolar transistor, the researchers have demonstrated a speed of 604 gigahertz - the fastest transistor operation to date."
their pseudomorphic heterojunction bipolar transistor
*blank stare*
What now? It's pronounced nu-cu-lar!
Switch back to Slashdot's D1 system.
Sure...it's fast now, but just wait until it goes into its depressive phase...
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~ |rip/\/\aster /\/\onkey
Yeah, because after the first 600 GHz, the next 400 GHz are a piece of cake.
Just in time for Longhorn!
Are you...Are you some kind of genius?
No, ma'am, I'm just a regular Slashdot reader.
More and more we here about these new HBT circuits that are faster than all get out.
The truth is that nothing will replace CMOS anytime soon. The infrastructure is already there, and it is being optimized over and over again and has a huge work force to man it.
I once heard someone ask Intel is they ever plan to switch to HBT for speed. Their response is, and will probably be for a while, that why would they switch technologies after investing $50 billion a year in their CMOS foundries etc.
These advancements may never make it to the point that the average consumer will take notice of them.
And it may be that these academic inventions will never find any market relevance.
I suspect the power requirements for this bi-polar transistor would make it impossible to build something on the scale of a P4.
Bipolar eats power.
I think these transistors, if found to be manufacturable, will probably be used in communications not digital logic.
Raydude
It all depends on the wiring delay and how many transistors deep a pipeline stage is.
fMax of a pipeline stage is 1/(switching times+wiring delays) under worst case thermal conditions. The wiring delays will stay about the same unless they're also improved by the new process, which is unlikely.
A 600GHz transistor, with really deep pipelines like the P4, and very good interconnect technology might allow 20-50GHz operation; but there are many other things to contend with (like thermals/dissipation) that can limit speed. Thermals, in turn, depend on the amount of capacitance being switched, which isn't specified here.
I think these transistors, if found to be manufacturable, will probably be used in communications not digital logic.
Indeed. The transistors used for digital circuits (i.e., computers) are mostly MOSFETs. The chief benefit of MOS transistors is that no current goes into the gate, so power is only used when switching from one state to the other (i.e. from a 1 to a 0).
Bipolar transistors have a base current (albeit small), so they draw power even when responding to a constant signal. However, they're faster and can output a lot more current than MOSFETs, so they do have plenty of other applications.
Terahertz transistors, indium phosphides, indium gallium arsenide, compositionally graded collectors, bases and emitters, reduced transit time and improved current density... And a pseudomorphic heterojunction bipolar transistor with speeds of 604 gigahertz.....
At times like this I like to leave a slashdot page open on articles and walk away from my computer.
Anybody walking past my computer looks at the screen and thinks 'JESUS! How clever is that guy?'
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