Toppan Develops World's First Flexible TFT to Withstand a Million Bending Cycles to a One Millimeter Radius of Curvature

TOKYO,March 29,2021 -- Toppan Printing (Toppan) (TYO: 7911),a global leader in communication,security,packaging,décor materials,and electronics solutions,has developed a flexible thin-film transistor (TFT) with an unprecedented combination of flexibility,durability,and carrier mobility.*1 The new TFT withstands a million bending cycles to a 1 mm radius of curvature and demonstrates advantages for practical application,such as an on/off current ratio of at least 107 with carrier mobility of 10cm2/Vs or more.

 

Flexible electronics are seen in foldable smartphones and their application is anticipated for wearable sensors,medical devices,smart packaging,and more. Organic TFTs are lightweight and flexible,but disadvantages include low carrier mobility,reliability,and durability. Inorganic TFTs provide high carrier mobility and have an established mass production process,but flexibility needs improvement. There is consequently demand for new TFTs combining outstanding carrier mobility,flexibility,and durability.

Leveraging unique technologies and a new structure,Toppan has created the world's first TFT with the flexibility to be wound around a mechanical pencil lead,the durability of a flexible printed circuit board,and carrier mobility exceeding 10 times that of amorphous silicon TFTs. Flex testing shows no variation in carrier mobility and other properties before and after a million bending cycles to a 1 mm radius of curvature. Toppan aims to advance manufacturing technology,enhance flexibility,and carrier mobility,and target the development of flexible sensors.

"We have achieved unprecedented flexibility and durability by combining existing TFT technologies," said Manabu Ito,development manager at Toppan. "This breakthrough raises the potential for ultra-thin,unbreakable flexible sheet sensors and stretchable devices in the future."

1. Carrier mobility

The ease with which carriers,such as electrons and holes,move through a semiconductor. Carrier mobility is one parameter for measuring transistor performance.

About Toppan

Toppan is a leading global provider of integrated solutions in the fields of printing,communications,electronics,and digital transformation. Toppan's global team of more than 50,000 employees offers optimal solutions enabled by industry-leading expertise and technologies to address the diverse challenges that businesses and society face in today's rapidly changing market.

https://www.toppan.com/en/