Dec. 2, 2002 - Many people in the auto identification business like to say that RFID will never replace bar codes, that bar codes will always be used for applications where even a five-cent RFID tag is too expensive. Those prognosticators may be reconsidering their position following the news this month that researchers at Infineon, the large German chipmaker, have successfully integrated plastics electronic circuits on commercially available packaging.

Thin-film chips can be on the bag.

The breakthrough makes very real the possibility that within five years ordinary bags of potato chips and boxes of cereal will have RFID microchips and antennas printed on them during the commercial printing process – much the way bar codes are printed on most products today. That means an infrastructure built to track pallets and cases with silicon-based RFID tags could be extended to track everything companies make, move and sell.

Researchers discovered back in 1977 that certain polymers -- organic or synthetic plastics with special, complex molecular structures -- could act as semiconductors. These plastics are cheaper than silicon, so the hope has always been that they could be turned into very inexpensive microchips. But researchers developing plastic chips have never been able to come close to matching the performance of silicon. Nor have they found suitable application for plastic chips.

Enter Dr. Guenter Schmid, head Infineon's polymer activities. Schmid and his team found a way to increase the performance of plastic, thin-film chips by using small-molecule organic semiconductors, instead of polymers. Because of their very tight molecular crystalline structure, these materials are better able to carry a charge. Schmid's team also depositing the active and most sensitive layer of the thin-film transistor last. The common approach is to lay down the "passivation" layer first.