Flexible 64 × 64 Pixel AMOLED Displays Driven by Uniform Carbon Nanotube Thin-Film Transistors

Carbon nanotube (CNT)
thin-film transistors are expected to be promising for use in flexible
electronics including flexible and transparent integrated circuits
and in wearable chemical and physical sensors and for driving the
circuits of flexible display panels. However, current devices based
on CNT channels suffer from poor performance uniformity and low manufacturing
yield; therefore, they are still far from being practical. This is
usually caused by nonuniform deposition of the semiconducting CNTs
and the rough surface of flexible substrates. Here, we report CNT
thin-film transistors (TFTs) driving a flexible 64 × 64 pixel
active matrix light-emitting diode display (AMOLED) by improving the
formation of uniform CNT films and developing a new pretreatment technique
for flexible substrates. The achieved AMOLED has uniform brightness
and a high yield of 99.93% in its 4096 pixels. More than 8000 TFTs
with high-purity semiconducting CNTs as the channel material show
an average on–off current ratio of ∼107 and
a carrier mobility of 16 cm2 V–1 s–1. The standard deviations of the on-state current
and the carrier mobility are 4.1 and 6.5%, respectively. Our result
shows that the panel driven by high-purity semiconducting CNTs is
a promising strategy for the development of next-generation flexible,
large-area displays.