from the bridging-small-gaps dept.
Nanotubes grown in place, an article by Eric Smalley in Technology Research News, reports the accomplishment of Stanford University researchers in growing individual carbon nanotubes directly between pairs of electrodes formed on a silicon wafer using photolithography. "The resulting nanotubes were 2.5 nanometers in diameter and spanned electrode gaps ranging from 3,000 to 10,000 nanometers." Anticipated applications include use in sensors, electromechanical transducers, and high frequency mechanical resonators. The research was published in the July 29, 2002 issue of Applied Physics Letters.
Archive for the 'MEMS' Category
from the bridging-small-gaps dept.
Gina Miller writes "IBM reported using MEMS/NEMS technology to achieve a data storage density of a trillion bits per square inch. The research project, code-named "Millipede," uses an array of 1024 (32 x 32) silicon cantilever AFM tips in a 3-mm square to make indentations 10 nm in diameter in a thin polymer film. Bits are written by heating the cantilever to 400 C, which softens the polymer film, and read at 300 C, where the polymer is not soft. Data is erased by using the tip to surround the data pit with a series of overlapping pits that fill in the old pit. The authors achieved more than 100,000 write/overwrite cycles to demonstrate this capability. They are currently using electronics that achieve kilobit-per-second data rates with individual tips, but expect to do much better with better electronics. A technical report on the Millipede project published in the June 2002 inaugural issue of IEEE Transactions on Nanotechnology can be downloaded from the IBM page. Soooo, the big question for nanodot readers, could this AFM array be useful for molecular manufacturing?"
The original paper is described in this abstract in Applied Physics Letters: ON-CHIP VACUUM MICROTRIODE. Integrated, solid-state design had many advantages over the old vacuum-tube style electronics. But some of the tube characteristics, such as the ability to handle high power, might be nice to have on a chip. With carbon nanotubes, acting as miniature emitters of electrons, this might be possible (See Update 454, http://www.aip.org/enews/physnews/1999/split/pnu45 4-2.htm). A new innovation in this regard is the development of an on-chip system of vacuum triodes. Scientists at Agere Systems (a company spun off from Lucent Technologies) build their chip using microelectromechanical (MEMS) technology; a lateral field of carbon nanotubes is grown on a cathode which can then be rotated into a vertical position in order to face a grid (10 microns away) and anode (100 microns away). Radar, electronic warfare, and satellite communications are expected to be the chief applications areas. (Bower et al., Applied Physics Letters, 20 May 2002)"
Gina Miller writes "Luke P. Lee, assistant professor of bioengineering at UC Berkeley, and his doctoral student Sunghoon Kwon have developed a miniature microlens and scanner that can see inside of a cell. "You could put this device on the tip of an endoscope that could be guided inside a cancer patient," said Lee. "Doctors could then see how tumor cells behave in vivo. It would also be feasible to deliver drugs directly to the tumor cell, and then view how the cell responds to the drugs." See the Berkeley Campus news site (3/13/02): http://www.berkeley.edu/news/media/releases/2002/0 3/13_micro.html"
eru writes "[The] press release from UC Berkeley details a proof-of-concept experiment wherein UC Berkeley professor Luke Lee successfully imaged (in 2-D) a lily's cell wall using a combination microlens and scanner, two devices which Lee has stated that he plans to incorporate into a fully miniaturized 3-D microscope in the future."
And Mr_Farlops points to additonal coverage in which "Science Daily reports that researchers at UC Berkeley have built a working array of confocal optical scanners, each one millimeter in size, built with photolithography methods. They plan to build even smaller devices and imagine uses in materials science, microscopic medical robots, cytology and microbiological research. Obviously such devices acting as the eyes of microscopic medical robots will revolutionize medicine even before nanoscopic cell repair robots arrive. I also personally find it significant that the article notes that this development is funded by, in part, by DARPA."
Read more for a longer post in this item from Brian Wang.
Following up on a previous Nanodot post (22 January 2002), here are a few additional items of interest to emerge from the MEMS 2002 Conference co-sponsored by the Institute of Electrical and Electronics Engineers (IEEE) and the Robotics and Automation Society, and held 20-24 January 2002 in Las Vegas, Nevada:
- "Computer chips tied to nanotech's future" (25 January 2002)
- "Nanotech research showing great progress" (27 January)
- "Microelectrodes could help blind see" (23 January). Additional information on this item can be found in this press release (24 January 2002).
Many of these UPI stories, as well as much original coverage of the conference, appeared on the Small Times website.
Mr_Farlops writes "Serendipity struck for chemists at the University of California, San Diego, after a chip of porous silicon, laced with gadolinium nitrate, exploded after being scratched. An article in the EE Times describes the nature of this discovery and speculates about the possible uses of the substance in microscopic rockets and explosive charges. It also sets the mind daydreaming about tiny fuses made of nested nanotubes filled with fuel and oxidizers."
Amid the conference focused on microdevices, some interesting nanotech-related news emerged from the MEMS 2002 Conference co-sponsored by the Institute of Electrical and Electronics Engineers (IEEE) and the Robotics and Automation Society, and held 20-24 January 2002 in Las Vegas, Nevada. A good general overview of the conference appeared on the Small Times website ("Record numbers at MEMS conference", by Jane Fried, 22 January 2002). Some of the highlights include:
- United Press International filed an interesting report ("Molecular motors could help research", by Scott R. Burnell, 21 January 2002) on an address by invited speaker Carlo Montemagno, a professor of mechanical and aerospace engineering at the University of California, Los Angeles and a staff researcher at the California NanoSystems Institute, described the motors and other microscopic devices to a conference on microelectromechanical systems or MEMS. The article is reposted on the Small Times site. "We've just started a project looking at … having small sensors locomote themselves where you want them to go," Montemagno said.
An interesting point raised in the UPI article was raised by Marlene Bourne, a technology research analyst, who said the biggest hurdle will be moving the devices to clinical applications. "If you start talking about machines in people's bodies, we're getting to the point where there will be some real questions about educating the public," Bourne told UPI. "(Another question is) do we need regulation in terms of how these (motors) will be used, for what purpose, and who gets to benefit from it?" Other roadblocks include working with the motors in a real-world environment, Montemagno said. They currently are limited to water-based solutions. Once the questions are resolved, however, the devices could reach the point of delivering chemotherapy drugs directly to cancer cells, Bourne said.
- Another UPI report ("Micro pump works without moving parts ", by Scott R. Burnell, 21 January 2002) describes work by Michael DeBar, a scientist with Eastman Kodak in Rochester, N.Y., who developed the idea of a "thermocapillary pump" while at the University of California at Berkeley. The article also is reposted on the Small Times site.
from the getting-cute-with-PR dept.
The press accounts indicate that a lot of people are just ga-ga over the silicon micro-device developed at Sandia National Labs. Described as a "Pac-Man-like microstructure" and the "gobbler", the device has silicon microteeth that open and close like jaws. The microjaws fit in a microchannel about one-third the width of a human hair (about 20 microns wide). When the jaws close, they trap a red blood cell. According to a Sandia press release on 20 August 2001, "The jaws, which open and close very rapidly, deform captured cells, and then, in less than the blink of an eye and almost playfully, let the little things loose. The blood cells travel on, regain their former shape and appear unharmed." [Playfully?]
Additional coverage can be found in this article from UPI. And Robert Trombatore writes: "A news item on the Scientific American web site details a just announced microdevice that can grab individual red blood cells flowing through a central channel. So far no practical uses, but the article mentions a few intriguing possibilities!"
TanMauWu writes "Wired has a story about "smart dust" that researchers at UC Berkeley have developed, which are essentially tiny light and temperature sensors that can network together. The suggested use for these sensors is to put lots of them in every room in a building and tie them all to a main computer that can regulate energy usage in the building to save energy. Of course, we can all think of *other* possible uses for this, can't we? Not quite true utility fog, but we're getting there."
from the Big-bugs-have-little-bugs dept.
Waldemar Perez calls our attention to an article on NanoElectroMechanical Systems (NEMS) in Technology Review Magazine ("NEMS: Machines Get Tiny," by David Voss, April 2001). In his opinion, Mr. Perez writes, "NEMS research promises to give us machines on the nanometer scale, [but this is] exactly there were critics argue Brownian motion will destroy them or make these machines unworkable and unreliable . . . these first generation NEMS prototypes will suffer from high wear (a well known problem on MEMS) until we can incorporate into them Drexler-type nanobearings and other devices."
from the top-down-pathway dept.
ScienceExpress, an online preprint service (login req'd) of Science magazine, published on Feb. 8 a report from Bell Labs/Lucent that MEMS can exploit the Casimir force. Coauthor Federico Capasso was quoted in the Feb. 10 Science News: "Capasso speculates that makers of MEMS and even tinier nanoelectromechanical systems may find ways to harness the Casimir force in 5 to 15 years…the experiment also indicates that the Casimir effect may become problematic for designers of tiny machines, says Paul J. McWhorter of MEMX…" CP: What's problematic to some may be a fun challenge to others — anyone care to give their view on this? Read more for the abstract.
from the thousands-of-steps-will-get-somewhere dept.
SteveLenhert writes "Integration of basic MEMS components is bridging the gap between micro- and nanotechnology. Very Large Scale Integration (VLSI) of basic electronic components such as diodes and transistors is well established. This article on Mechanical VLSI describes approaches to (and implications of) VLSI of mechanical components such as actuators and cantilevers.
from the take-it-from-the-top-down dept.
Waldemar Perez writes "This is one of the most interesting articles I have found on NEMS. It was published in Physics World magazine and talks about some early NEMS working prototypes and the challenges facing NEMS.
from the manufacturing-architectures dept.
Some Fat Guy writes "There is an interesting paper and Real Video animations on Exponential Assembly here: http://www.zyvex.com/Research/exponential.html The devices described are MEMS devices, but the concept scales down." CP: A more formal journal article from the Foresight Conference is linked to at the end.
from the he-knows-if-you've-been-bad-or-good dept.
EddieWehri brings our attention to an article in the San Francisco Chronicle: "Yep, yet one more SF concept from books like The Diamond Age make it into prime time. MEMS science is producing dust sized surveillence devices that are lighter than air and float around collecting data and reporting back to the mother base." Excerpt: "Each mote contains a solar cell to generate power, sensors that can be programmed to look for specific information, a tiny computer that can store the information and sort out which data is worth reporting, and a communicator that enables the mote to be 'interrogated' by the base unit…'This is a technology of total surveillance' "
from the now-open-wide dept.
Mark Baltzegar brings our attention to plans for a confocal imaging "scanning microprobe" using MEMS technology which would enable imaging of living cells deep within the human body. "Currently we have no way to effectively study the real living behavior of cells in detail because we lack the advanced visualization tools to see them in their natural environment," commented Dr. John Liddicoat, Cardiac Surgeon at Allegheny General Hospital in Pittsburgh, PA. "The opportunities for real-time visualization down at the cell level would be incredibly valuable. We could realize a broad range of uses in medicine. For example, by applying this technology, we may be able to accurately direct pharmacological and mechanical interventions in such diverse fields as cardiology, pulmonolgy, oncology, and transplantation, just to name a few. This type of visualization tool would be enormously valuable."
from the top-down-bottom-up-whatever-works dept.
Senior Associate Brian Wang brings to our attention a press release from the University of Illinois at Chicago on work presented at the BioMEMs & Biomedical Nanotechnology World 2000 conference: "Another example of therapeutic BioMEMs that Desai will discuss are cell encapsulation devices with nanometer-sized pores that can protect implanted cells or components from large molecules like antibodies while allowing small molecules like hormones and nutrients to freely pass through. Such devices, which have long been dreamed of for implanting pancreatic islet cells in diabetic patients or neurosecretory cells in Parkinson's or Alzheimer's patients, are now being fabricated in Desai's laboratory by micro-machining silicon to create precisely controlled micro- and nano-architectures."
from the really-tiny-scrubbing-bubbles dept.
GinaMiller (and others) wrote "Simulation shows that liquid jets a few nanometers in diameter might have the potential to produce ever-smaller electronic circuitry, inject genes into cells, or etch tiny features. Writing in the August 18 issue of Science, Georgia Tech researchers suggest that jets as small as six nanometers in diameter may be possible — though they will require special conditions to operate and be sensitive to effects not of concern to macroscopic jets. As a next step, the researchers would like to create nanojets experimentally and use them to apply patterns that could replace current lithographic processes in the manufacture of nanoscale miniaturized circuits. They could potentially also be used as "gene guns" to insert genetic materials into cells without causing damage. The researchers produced some nice graphics "
from the where-oh-where-is-good-software dept.
Senior Associate Michael Butler writes "At the just-past Foresight Gathering, mention was made of extant MEMS fab CAD software packages and how bad they are. Alternatives mentioned include, e.g., recycling mature finite element FORTRAN code and stitching it together with other things. It happens that Matra open sourced a bunch of CAD/CAM code last year. (Slashdot article). I suggest that interested people at Zyvex and elsewhere check out Open Cascade and see if what they're doing can be bent to your purposes. Have any nanodotters worked with this code?