Featured Research

from universities, journals, and other organizations

New Sensor Bares Faults In Smallest Possible, Most Advanced Circuits

Date:
May 12, 2003
Source:
Brown University
Summary:
A new scanning microscope developed at Brown University can uncover defects in the smallest and most complex integrated circuits at a resolution 1,000 times greater than current technology. The scanner removes a barrier to further shrinking of integrated circuits: As circuits get smaller, non-visual defects become harder to find.

A new scanning microscope developed at Brown University can uncover defects in the smallest and most complex integrated circuits at a resolution 1,000 times greater than current technology. The scanner removes a barrier to further shrinking of integrated circuits: As circuits get smaller, non-visual defects become harder to find.

"This microscope will allow manufacturers to find defects in each embedded wire in ever-tinier circuits," said Brown University professor Gang Xiao. He developed the instrument's hardware and software with Ben Schrag, who will receive his Ph.D. at Brown this month.

The microscope's magnetic-scanning technology suggests a new small, non-invasive form of remote detection, said the researchers, who envision a "pass-over and detect" magnetic-sensor-tipped pen, for use in finding internal cracks within aircraft, sensing biological agents in the environment or body, or recognizing counterfeit bills or other objects.

Although magnetic sensing is used extensively, it is not applied widely for imaging electrical current flow, said Schrag. The only method that uses magnetic imaging to see current flow is restricted to extremely low temperatures, employing cryogenic aids such as liquid nitrogen. However, the Brown device works at room temperature. This design opens the way to greater use of magnetic sensing technology, he said.

"The factor of 1,000 improvement in spatial resolution is how much better we can do than this cryogenic technology," Schrag said. "We are just scratching the surface of potential applications."

Xiao and Schrag are using the technology to pinpoint how electrical current can form pinholes in state-of-the-art devices called magnetic tunnel junctions. These tiny sandwiches of ferromagnetic layers and insulating material are candidate memory storage cells to replace standard cells used in computer memory chips.

The researchers have "imaged" current flow in electrical components as small as 50 nanometers, the smallest commercially available components, half the size of conventional chips.

Until now, little or no technology existed for actually "watching" electrical current flow, said Schrag. Whenever current runs through wires, such as those embedded within the semiconducting material of an integrated circuit, it creates a magnetic field. By measuring spatial changes in that magnetic field, the microscope visualizes electrical current, even within wires buried under layers of advanced materials, he said.

"The device allows us to see the evolution of hot spots on each wire in a circuit and how each defect moves down the wire in the form of electrons moving atoms," said Xiao. "To see a collection of atoms moving as a function of time is a capability that did not exist until now. We are witnessing the flow of electricity. It appears similar to an image of human blood flowing."

The microscope is described in a paper in the May 12, 2003, issue of Applied Physics Letters. It features some of the same magnetic-scanning technology found in computer hard drives. A scanner does not touch what it reads. Instead, a magnetic sensor the size of a small pea moves quickly back and forth over a circuit through which current flows. The sensor collects information, which is then converted by algorithms into a color picture of electron flow. Color changes in the image reflect the intensity of electron flow as well as the presence of defects.

About the size of a refrigerator, the microscope is being reduced to the size of a desktop computer. "The new design will allow a technician to sit in front of a monitoring screen, as integrated circuits pass through a small open door, under a scanner and out the door," Xiao said. Currently, the microscope takes a few minutes to scan a circuit. The researchers are working to reduce that time to as little as 30 seconds.

###

Xiao and Schrag have filed patents on several aspects of the technology, which has been transferred to Micro Magnetics, a Fall River, Mass., company that makes scanning devices for manufacturers of integrated circuits (computer chips). Images produced by the microscope may be viewed at http://www.micromagnetics.com/.

The National Science Foundation funded this work.


Story Source:

The above story is based on materials provided by Brown University. Note: Materials may be edited for content and length.


Cite This Page:

Brown University. "New Sensor Bares Faults In Smallest Possible, Most Advanced Circuits." ScienceDaily. ScienceDaily, 12 May 2003. <www.sciencedaily.com/releases/2003/05/030512074130.htm>.
Brown University. (2003, May 12). New Sensor Bares Faults In Smallest Possible, Most Advanced Circuits. ScienceDaily. Retrieved July 25, 2014 from www.sciencedaily.com/releases/2003/05/030512074130.htm
Brown University. "New Sensor Bares Faults In Smallest Possible, Most Advanced Circuits." ScienceDaily. www.sciencedaily.com/releases/2003/05/030512074130.htm (accessed July 25, 2014).

Share This




More Matter & Energy News

Friday, July 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

TSA Administrator on Politics and Flight Bans

TSA Administrator on Politics and Flight Bans

AP (July 24, 2014) TSA administrator, John Pistole's took part in the Aspen Security Forum 2014, where he answered questions on lifting of the ban on flights into Israel's Tel Aviv airport and whether politics played a role in lifting the ban. (July 24) Video provided by AP
Powered by NewsLook.com
Creative Makeovers for Ugly Cellphone Towers

Creative Makeovers for Ugly Cellphone Towers

AP (July 24, 2014) Mobile phone companies and communities across the country are going to new lengths to disguise those unsightly cellphone towers. From a church bell tower to a flagpole, even a pencil, some towers are trying to make a point. (July 24) Video provided by AP
Powered by NewsLook.com
Algonquin Power Goes Activist on Its Target Gas Natural

Algonquin Power Goes Activist on Its Target Gas Natural

TheStreet (July 23, 2014) When The Deal's Amanda Levin exclusively reported that Gas Natural had been talking to potential suitors, the Ohio company responded with a flat denial, claiming its board had not talked to anyone about a possible sale. Lo and behold, Canadian utility Algonquin Power and Utilities not only had approached the company, but it did it three times. Its last offer was for $13 per share as Gas Natural's was trading at a 60-day moving average of about $12.50 per share. Now Algonquin, which has a 4.9% stake in Gas Natural, has taken its case to shareholders, calling on them to back its proposals or, possibly, a change in the target's board. Video provided by TheStreet
Powered by NewsLook.com
Robot Parking Valet Creates Stress-Free Travel

Robot Parking Valet Creates Stress-Free Travel

AP (July 23, 2014) 'Ray' the robotic parking valet at Dusseldorf Airport in Germany lets travelers to avoid the hassle of finding a parking spot before heading to the check-in desk. (July 23) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

    Health News

      Environment News

        Technology News



          Save/Print:
          Share:

          Free Subscriptions


          Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

          Get Social & Mobile


          Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

          Have Feedback?


          Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
          Mobile: iPhone Android Web
          Follow: Facebook Twitter Google+
          Subscribe: RSS Feeds Email Newsletters
          Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins