Radio Frequency Electronics in a-IGZO TFT Technology (Invited)

This paper reviews the recent progress of active high-frequency electronics on plastic, and gives an outlook towards future advances of radio-frequency electronics in the amorphous Indium Gallium Zinc Oxide (a-IGZO) thin-film transistor (TFT) technology. Our a-IGZO technology is mechanically flexible, bendable and stretchable. A 0.5 mu m TFT achieved a measured transit frequency of 138 MHz. We have presented several high-frequency circuits integrated in this a-IGZO technology, including several RF amplifiers and a fully-integrated AM receiver. The receiver consists of a four-stage cascode amplifier, an amplitude detector, a baseband amplifier, and a filter. At a DC current of 7.2 mA and a supply of 5 V, a conversion gain above 15dB was measured from 2 to 20MHz. Based on these works, we are investigating a wireless transmitter to be fully integrated on a plastic film. Some simulation results of a ring-oscillator based on-off-keying modulator and an LC voltage controlled oschillator under investigation are presented.