Modification/Crystallization of Nanolayers on Heat Sensitive Substrates (e.g. PET) by Ultrashort Thermal Annealing in the Millisecond Range

摘要

Novel applications of thin film deposition techniques cause a strong demand for new low temperature deposition technologies of semiconductor, metallic or transparent conductive oxide (TCO) layers. However, the optical and electrical properties of layers deposited at low temperatures are usually not meeting application requirements and therefore they need to be improved by subsequent annealing. Such annealing steps are typically limited in temperature (＜ 200°C for flexible substrates, ＜ 500°C for glass) to avoid substrate damage. This implies relative long annealing times - which is usually in contradiction to the intended use of fast in-line or roll-to-roll processing. This is the driving force to establish new post-deposition annealing technologies for surface modification, in order to integrate these methods into next generation highspeed / high-throughput fabrication equipment. Flash lamp annealing (FLA) allows the annealing of near surface layers at high temperatures (＞ 500°C) within milliseconds without damaging deeper layers or the bulk material. Results of optical and electrical parameters after FLA treatment of different layers are presented.