Organic Metal used to realize the conductive pattern
Computer chips will no longer be necessarily based on silicon as the semiconducting material, at least if the Dutch multinational electronic concern Philips had its way. Five research scientists succeeded in constructing the first integrated circuit exclusively consisting from "plastic" (to be more precise: from organic polymers) in Philips R&D center in Eindhoven (Netherlands). This news was pre-published in the leading international scientific magazine "Nature"1. The original paper is being published in "Applied Physics Letter".
The chip's base is a polyimide wafer fitted with 326 transistors and more than 300 vertical contacts being a complete 15-bit programmable code-generator. The semiconducting material is the conjugated polymer Polythienylenvinylen, Polyvinylphenol is used as the isolating component, while the Organic Metal Polyaniline constitutes the electrode. The transistor structures are created by irradiating the Organic Metal with UV beams (with the help of a mask), resulting in a decrease of conductivity by almost ten orders of magnitude, which is necessary for functioning in a transistor. The vertical electric contacts are made with very fine printer needles, while the pressing power ensures the Polyaniline layers to get in contact with each other in the holes.
Thus an integrated circuit could be demonstrated for the first time, which manufacturing process is incredibly simple compared to the conventional procedure. On the other hand the chip performance needs further improvement: with only 30 bits per second, the new plastic chip is still far from being useable in today's computers and laptops. However, an application in electronic bar codes or water-marks is forseeable. On a long-term basis, the development chances of plastic chips are enormous, because charge carrier mobility has already been shown principally like in amorphous silicon.
This first publication only represents the very first beginning of a following ambitious R&D project. According to C. Drury, one of Philips research scientists, the company is prepared to develop this new technology to industrial and market maturity.
First contacts between Philips and Ormecon Chemie GmbH have been established, because the new chip only works on the basis of Ormecon's patent protected Organic Metal and is additionally using a process also being developed and patented by Ormecon Chemie.
Ormecon Chemie GmbH2 is the world's first and still only company to commercially manufacture and market the Organic Metal (after almost 20 years of basic research). This new material is currently applied in corrosion protection systems and in a new solderable surface finish for printed circuit boards. These applications are the basis for Ormecon's soon expected economical breakthrough. While Ormecon Chemie is operating in the large and traditionally oriented corrosion protection market with a pioneering and revolutionary new technology, the new surface finish represents a promising technology in the innovative market of printed circuit board manufacturing.
Other applications of the Organic Metal could be as transparent electrodes in new polymeric light emitting diodes, in sensors or in other, still unexpected nanotechnological applications, e.g. in optoelectronics.
A cooperation between Philips and Ormecon Chemie could be pushed and dynamically supported by the cooperation between DuPont (Wilmington, DE, USA) and Ormecon Chemie, which has already assumed more concrete forms (see press release 1998, available on request).
(Dr. Bernhard Weßling)
