Transparent electronics based on transfer printed aligned carbon nanotubes on rigid and flexible substrates

We report high-performance fully transparent thin-film transistors (TTFTs) on both rigid and flexible substrates with transfer printed aligned nanotubes as the active channel and indium-tin oxide as the source, drain, and gate electrodes. Such transistors have been fabricated through low-temperature processing, which allowed device fabrication even on flexible substrates. Transparent transistors with high effective mobilities (∼1300 cm ² V ^-1 s ^-1) were first demonstrated on glass substrates via engineering of the source and drain contacts, and high on/off ratio (3 × 10 ⁴) was achieved using electrical breakdown. In addition, flexible TTFTs with good transparency were also fabricated and successfully operated under bending up to 120°. All of the devices showed good transparency (∼80% on average). The transparent transistors were further utilized to construct a fully transparent and flexible logic inverter on a plastic substrate and also used to control commercial GaN light-emitting diodes (LEDs) with light intensity modulation of 10 ³. Our results suggest that aligned nanotubes have great potential to work as building blocks for future transparent electronics.