Record performance of dual-gate organic TFT-based RFID circuit

At today's International Solid State Circuit Conference (ISSCC), Holst Centre, Imec and TNO present a dual-gate-based organic RFID chip with record data rate and lowest reported operating voltage. For the first time, the advantages of dual gate transistors in circuit speed and robustness have thereby been exploited in a complex organic-electronic circuit.

Organic RFID tags are one of the drivers of flexible electronics research and development.

The current result of a 64-bit transponder circuit at 4.3kb/s shows an improvement of over a factor two compared to the result reported last year at ISSCC. What’s more, results show that chips start to operate at lower voltages (down to 10V), making them more suitable for capacitive and inductive coupling with a readout station.

Main reason behind the increased performance is the use of a dual gate unipolar transistor technology, adapted from rollable-display company Polymer Vision, one of the partners in the Holst Centre research programs. Using a dual gate allows controlling the threshold voltage (Vt) and the thus obtained multiple-Vt technology leads to more robust circuits.

Dual-gate organic TFT (thin-film transistor) circuits have been reported before, but had never surpassed the complexity of basic inverters. Thanks to the tight collaboration within mixed teams of circuit designers and technology developers, Holst Centre, imec and TNO now report 99-stage dual-gate ring oscillators in various topologies, plus 64-bit RFID transponder chips using the same architecture.

Further and ongoing work will demonstrate the viability of the technology towards industrial uptake.