Featured Research

from universities, journals, and other organizations

In Place Fabrication Solves Organic Polymer Shortcoming

Date:
September 9, 2003
Source:
Penn State
Summary:
Just like the manufacturers of silicon electronics, a team of Penn State chemical engineers wants to assemble circuit boards in place, but these circuits are made of conducting organic polymers that pose major fabrication roadblocks.

Just like the manufacturers of silicon electronics, a team of Penn State chemical engineers wants to assemble circuit boards in place, but these circuits are made of conducting organic polymers that pose major fabrication roadblocks.

"We want to build electronic devices like transistors and flexible circuits," says Dr. Seong Kim, assistant professor of chemical engineering.

Kim and Sudarshan Natarajan, graduate student in chemical engineering, looked at fabricating circuits from polythiophene. This conjugate conducting organic polymer is easily made in a beaker, but once the polymer is created from chaining together a series of identical smaller molecules – monomers – it is a powder that cannot be molded or used for film coating.

"Conjugate conducting polymers are not soluble nor are they meltable," Kim told attendees at the annual meeting of the American Chemical Society today (Sept. 8) in New York. "Some researchers have made them soluble by adding elements to the polymer backbone, but making circuit boards with these is difficult and requires high energy."

Kim and Natarajan solve the fabrication problem by combining the synthesis and processing steps, which are done separately in conventional methods, into a single step.

"We bypass the problem," says Kim. "We make the material at the site of application."

The researchers use a prepared substrate and deposit the monomer – the small molecule that chains to make the polymer – using standard physical vapor deposition. Once they have a thin film of the monomer on the substrate, they apply a mask, similar to those used in standard silicon electronics manufacture, to the surface. The masked monomer film is then exposed to ultraviolet light.

The light causes two monomers to join forming a dimer, then a third molecule to form a trimer and so on. Dimers and trimers then join to begin forming the much longer polymer chains until all the monomer exposed to light is polymerized.

This reaction differs from normal polymerization where the chain begins at one point and grows by adding individual monomers. In this new process, monomers are joining each other wherever they are struck by the photons in the ultraviolet light. The process takes about seven minutes to complete. The researchers then wash off the soluble, uncoupled monomers, leaving only the pattern of conducting polymers indicated by the mask.

Aiming to incorporate conjugate conducting organic materials into the current silicon-based microtechnology, the researchers tried a variety of inorganic substrates including copper, gold and silicon.

However, neither copper nor silicon will make a flexible circuit, so the researchers are also investigating using other flexible substrates such as plastics. A circuit made on plastic materials would find applications where the flexibility is critical. For example, flexible circuits would be ideal for lightweight flexible-screen displays creating electronic paper.

A variety of conducting polymers are also light emitting. The proper combination of red, yellow and green can produce full color images. Another example would be in biomedical applications.

The researchers are looking at a variety of other organic conducting polymers for use in in-place fabrication of circuits and electronic devices.

A seed grant from Penn State's National Science Foundation-supported Materials Research Science and Engineering Center seed grant supported this work.


Story Source:

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


Cite This Page:

Penn State. "In Place Fabrication Solves Organic Polymer Shortcoming." ScienceDaily. ScienceDaily, 9 September 2003. <www.sciencedaily.com/releases/2003/09/030909070747.htm>.
Penn State. (2003, September 9). In Place Fabrication Solves Organic Polymer Shortcoming. ScienceDaily. Retrieved July 24, 2014 from www.sciencedaily.com/releases/2003/09/030909070747.htm
Penn State. "In Place Fabrication Solves Organic Polymer Shortcoming." ScienceDaily. www.sciencedaily.com/releases/2003/09/030909070747.htm (accessed July 24, 2014).

Share This




More Matter & Energy News

Thursday, July 24, 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