VTT prints thin film transistors using roll-to-roll technique

Thin film transistors can now be manufactured using roll-to-roll techniques - such as printing - for the deposition of patterns on the substrate layer of film; a development that could expand the range of electronic components and products, while reducing their production costs.

According to VTT, thin film transistors are more suitable than traditional silicon chip transistors for applications such as large-surface display screens, certain sensor applications, toys, games and smart cards.

For transistor technology, roll-to-roll fabrication techniques are said to have a range of advantages that include the possibility to use large surface areas, plus mechanical flexibility, transparency and low production start-up costs. Until now, production of thin film transistors has typically been only partly based on roll-to-roll techniques, resulting in unattractive mass production costs.

VTT’s thin film transistor production techniques were developed as part of the EU-funded POLARIC (Printed, Organic and Large-Area Realisation of Integrated Circuits) research project.

With the aid of a unique self-aligning technique, the method under development eliminates the challenge of aligning the patterns in the different thin film layers accurately against each other in the roll-to-roll process. In addition, the pattern size for transistor components is claimed to be pushed to the limit of minuteness possible for printing techniques.

VTT’s goal is to keep developing the technology until it matures enough to provide a springboard for new business activities. To this end, VTT is now seeking companies interested in developing applications based on printed thin film transistors.

According to IDTechEx’s ‘Printed, Organic and Large-Area Realisation of Integrated Circuits’ report, the markets for thin film transistors will grow from their current value of $3m to around $180m over the next decade.