IBM Develops 100 GHZ Nanotube Transistor - Page 1
Forum section: electronics / general

author: SgtRock
author_rank: Unknown
timestamp: February 05, 2012, 07:16:52 pm
content: Greetings EEVBees:--Please see the below link to an article in The Register by Richard Chirgwin, about IBM's new 100 GHZ Nanotube Transistor. There are also recent articles in "Science", "Nano Letters" and "Technology Review".http://www.theregister.co.uk/2012/01/26/ibm_nanotech_graphene_and_nanotubes/"Aaron Franklin, a researcher at IBM’s Watson research centre, told Technology Review it’s important to prove that nanotubes can be fabricated with such small feature sizes: quite simply, there’s not much point researching materials that can’t beat silicon’s geometry."--I was hoping that some of you, who are familiar with this sort of thing (and who hopefully can see over the pay walls in the cited publications), would comment on its implications."If you had had a nickel for every nickel that he has, you would have a lot of nickels."Albert Einstein 1879 1955Best RegardsClear Ether

author: wkb
author_rank: Super Contributor
timestamp: February 05, 2012, 09:53:58 pm
content: Quote from: wilfred on February 05, 2012, 08:43:33 pmGiven that he was involved in the start of the Manhattan Project he could have been dead by 1936

author: Unknown
author_rank: Unknown
timestamp: February 05, 2012, 09:57:32 pm
content: My impression, after quickly skimming the Sciencexpress article, is that their method improves the off resistance, which is helpful to keep leakage down to manageable levels in ICs. It's not faster than previous graphene-based FETs, but these had too much leakage for use in ICs. They do appear to require rather large gate voltages and have trouble producing devices with a larger barrier thickness that would combat this. So don't design in those transistors in your products just yet.

author: ejeffrey
author_rank: Super Contributor
timestamp: February 05, 2012, 10:32:29 pm
content: So there are two announcements here that the register has 'helpfully' combined into one article:A graphene transistor operating at 100 GHz, with a relatively large size device.A nanotube transistor fabricated with a 10 nanometer long nanotube.Carbon nanotubes are great stuff, and have a bunch of potentially useful applications, but they are not going to be bread-and-butter electronic, probably ever. They will likely be relegated to the same style of niche applications that exotic semiconductors currently occupy -- applications like microwave amplifiers and mixers. Growth of carbon nanotubes is still essentially a random process. As far as I know, every nanotube device is built by one of three methods. First, grow a bunch of nanotubes on a wafer. Throw it in an SEM and see where the nanotubes are, then build your devices on top of them. The second method is to build a device on a silicon wafer with contact pads, grow your nanotubes nearby, then use a nanomanipulator to place the nanotubes across the pads. The final possibility is basically prayer: you build a device, chuck some nanotubes on it, and hope that one lands in the right place.As you can imagine, none of the those methods is really commercially viable, at least beyond high margin devices for special applications. Even then you can really only do it for a handful of nanotubes per circuit.Graphene is like a fab friendly version of nanotubes. It has similarly useful electronic properties, but it can already be grown in single-layer thickness over relatively large areas. I wouldn't bet on it replacing silicon anytime soon, but it is at least plausible that we could see something like a graphene CPU, although I wouldn't hazard a guess as to when. Graphene so far has been a blockbuster success. While a great many other technologies including the other novel carbon structures like nanotubes and buckyballs have shown great promise and been hailed as silicon killers, they have all run into problem after problem. Graphene has gone from discovery to nearly application ready in record time, and it shows incredible promise, but it still is mostly promise. There is also definitely a lot of 'if all you have is a hammer' syndrome surrounding graphene. In the frenzy to test every conceivable property of graphene, people have tended to get caught up in the idea that graphene is the best material in the world at everything. So you have to exercise a degree of healthy skepticism about many of the claims.

author: SgtRock
author_rank: Unknown
timestamp: February 06, 2012, 05:37:11 pm
content: Dear Wilfred and Wkb:--Indeed you are correct, I know better I just was not paying sufficient attention. I have several Einstein quotes I use and they all had the incorrect date. He could hardly have written that letter to Roosevelt if he were dead. Mea Culpa.--Dear Alm and Ejeffery:--Thanks for your informative posts."Reality is merely an illusion, albeit a very persistent one."Albert Einstein 1879 1955Best RegardsClear Ether

author: Mechatrommer
author_rank: Super Contributor
timestamp: February 06, 2012, 11:24:08 pm
content: Quote from: SgtRock on February 06, 2012, 05:37:11 pmhow do you know you are dreaming if you are unable to wake up from that dream?

author: Hypernova
author_rank: Unknown
timestamp: February 08, 2012, 04:27:46 am
content: Quote from: Mechatrommer on February 06, 2012, 11:24:08 pmIf you cannot wake up from a dream, does it matter that you are dreaming?

author: Spiro
author_rank: Contributor
timestamp: February 08, 2012, 02:20:56 pm
content: Bitch pleaseInP Heterojunction Bipolar Transistor with ft > 750GHz!!!I cannot find article about that, but I am sure I read that they said something abouttransistors with ft bigger than 780GHz!!!

author: Unknown
author_rank: Unknown
timestamp: February 08, 2012, 03:20:58 pm
content: Quote from: Spiro on February 08, 2012, 02:20:56 pmWhat is this. Infrared?meh...LEDs already do that