Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


In place fabrication solves organic polymer shortcoming


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.

A’ndrea Elyse Messer | EurekAlert!
Further information:

More articles from Life Sciences:

nachricht Novel mechanisms of action discovered for the skin cancer medication Imiquimod
21.10.2016 | Technische Universität München

nachricht Second research flight into zero gravity
21.10.2016 | Universität Zürich

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>