Featured Research

from universities, journals, and other organizations

Chemical Microscope Enabled: Imaging Of Materials At The Nanometer Scale

Date:
May 13, 1999
Source:
Max Planck Society
Summary:
The modern way of microscopy relies on a tiny tip scanning over a surface to sense feeble currents or forces, to build a relief image in the computer. That the tip can also sense the infrared vibrations of the surface material, thus revealing the material´s chemical composition, is described by researchers at the Max Planck Institute for Biochemistry (Max-Planck-Institut für Biochemie), Martinsried/Germany, in their letter to Nature appearing on May 13.

The modern way of microscopy relies on a tiny tip scanning over a surface to sense feeble currents or forces, to build a relief image in the computer. That the tip can also sense the infrared vibrations of the surface material, thus revealing the material´s chemical composition, is described by researchers at the Max Planck Institute for Biochemistry (Max-Planck-Institut für Biochemie), Martinsried/Germany, in their letter to Nature appearing on May 13.

Related Articles


The classical optical microscope is limited in its resolution by the wavelength, in practice to just below one micrometer. To visualize nanoscale structures - which are of growing interest in electronics, materials and biology - one can use the electron microscope which needs however high vacuum and special sample preparation. More generally usable are the scanning tip microscopes such as the tunneling or atomic force microscope, who function by moving a sharp sensor tip along a surface. Feeble electric currents or mechanic forces are registered and compilated in a computer to form the surface´s relief image or topography. These techniques can however not find out which chemical substances are present where on the surface.

The physicists at the Max Planck Institute show that infrared waves can accomplish just this. They employ a well-known material response, the infrared vibrational absorption, to identify the chemical composition of the surface. While the use of infrared spectroscopy for the identification of macroscopic samples has been a standard technique in chemical and semiconductor plants, as well as in physics and biology research, the surprising news is that this long-wavelength technique should be combinable with the scanning tip microscope principle.

In the experiment, a metal tip moves close to a polymer film composed of different compounds, and the surface topography is recorded in usual AFM (atomic force microscope) manner. At the same time the tip is illuminated by an infrared beam. Much as by an antenna the infrared wave is concentrated at the very apex of the tip where it senses the local absorption of the closeby sample. The compiled infrared image overlaid with the topography shows where the more absorbing substance is, by being darker. When a different infrared wavelength is employed the infrared image changes its contrast accordingly.

The letter accomplishes demonstrating how to identify material composition on a nanoscale, using a scanning metal tip. This includes a theoretical description of the infrared near-field interaction which is predicted to be enhanced, an effect already partly verified in the experiment. The enhancement is due to the metal electrons of the tip lending absorption strength to the sample vibration. The enhancement mechanism strongly amplifies the potential of the new microscope because weaker absorbers can be identified and the resolving power can be increased.

Other techniques of identifying material composition on a nanoscale are not available. The optical near-field microscope is color-blind concerning the material-specific absorption resonances because these occur at infrared wavelengths in the range of 3 to 30 micrometers.

The results lay the foundation to develop a generally usable infrared microscope with at least 100 nm resolution, possibly 10 nm or even better. The next steps are to achieve a dual or multifrequency simultaneous imaging, to be followed by broadband infrared operation. Suitable infrared lasers exist. The chemical microscope will be complete once a full infrared spectrum can be mapped at each pixel, revealing the local material´s identity. Apart from widening the infrared illumination spectrum the development will have to focus on sharper tips, sharper optical alignment and tighter mechanical control.


Story Source:

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


Cite This Page:

Max Planck Society. "Chemical Microscope Enabled: Imaging Of Materials At The Nanometer Scale." ScienceDaily. ScienceDaily, 13 May 1999. <www.sciencedaily.com/releases/1999/05/990513065521.htm>.
Max Planck Society. (1999, May 13). Chemical Microscope Enabled: Imaging Of Materials At The Nanometer Scale. ScienceDaily. Retrieved December 22, 2014 from www.sciencedaily.com/releases/1999/05/990513065521.htm
Max Planck Society. "Chemical Microscope Enabled: Imaging Of Materials At The Nanometer Scale." ScienceDaily. www.sciencedaily.com/releases/1999/05/990513065521.htm (accessed December 22, 2014).

Share This


More From ScienceDaily



More Matter & Energy News

Monday, December 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Touch-Free Smart Phone Empowers Mobility-Impaired

Touch-Free Smart Phone Empowers Mobility-Impaired

Reuters - Innovations Video Online (Dec. 21, 2014) — A touch-free phone developed in Israel enables the mobility-impaired to operate smart phones with just a movement of the head. Suzannah Butcher reports. Video provided by Reuters
Powered by NewsLook.com
Building Google Into Cars

Building Google Into Cars

Reuters - Business Video Online (Dec. 19, 2014) — Google's next Android version could become the standard that'll power your vehicle's entertainment and navigation features, Reuters has learned. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
AP Review: Nikon D750 and GoPro Hero 4

AP Review: Nikon D750 and GoPro Hero 4

AP (Dec. 19, 2014) — What to buy an experienced photographer or video shooter? There is some strong gear on the market from Nikon and GoPro. The AP's Ron Harris takes a closer look. (Dec. 19) Video provided by AP
Powered by NewsLook.com
Obama: Better Ways to Create Jobs Than Keystone Pipeline

Obama: Better Ways to Create Jobs Than Keystone Pipeline

AFP (Dec. 19, 2014) — US President Barack Obama says that construction of the Keystone pipeline would have 'very little impact' on US gas prices and believes there are 'more direct ways' to create construction jobs. Duration: 00:47 Video provided by AFP
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:

Strange & Offbeat Stories

 

Space & Time

Matter & Energy

Computers & Math

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