The LAFLEXEL project aims to deliver high performance metal-oxide thin‐film transistors (TFTs) by introducing a photonic process, namely laser annealing. Laser annealing an ultra-fast and macroscopically cold process which avoids the harmful effect of thermal processing and can thus be used in conjunction with temperature sensitive substrates - for example, when treating components built onto polymeric substrates. A laser beam is moved and manipulated rapidly to process large areas, while maintaining high spatial resolution for selective patterning / annealing. The proposed process can significantly enhance performance and reduce costs for high-tech applications by offering precise control, robustness, extended lifetime, high capacity and lower consumable expenses.
• Identify the most appropriate laser annealing system design and processing parameters.
• Investigate facile optimisation of the process conditions using systems to meticulously vary parameters, including fluence, number of pulses, wavelength, environmental parameters (pressure, chemical composition) and temperature of the substrate.
- Fabricated indium oxide-based TFTs, prepared by spin-coating - in collaboration with Imperial College London.
- Metal oxide conversion was confirmed, excimer laser annealing (ELA) changed electrical characteristics in specific ares of the film, very low leakage current, good ON-OFF current ratio.
- Fabricated indium zinc oxide transistors with similar performance but highly improved threshold voltage, compared to thermally annealed counterparts - in collaboration with University of Cambridge.
- This mild thermal annealing process (two thermal annealing steps (at 120°C) separated by ELA) shows potential for preparation of oxide TFT devices on polymeric substrates.
- Fabricated high performance a-IGZO (sputtered) TFTs on flexible substrates - in collaboration with PragmatIC Printing.
- Improved performance of TFTs in terms of hysteresis and ON-OFF current ratio.