Welding of Silver Nanowire Networks Via Flash White Light and UV-C Irradiation for Highly Conductive and Reliable Transparent Electrodes

Transparent conductive electrodes (TCEs) with high electrical conductivity and good optical transparency have been widely used in numerous flexible electronic devices, such as touch screens, active-matrix LCDs, light emitting diodes, and solar cells. Different materials have been utilized to make TCEs, including indium tin oxide (ITO), fluorine-doped tin oxide (FTO), graphene, carbon nanotubes (CNTs), and metal nanowires (e.g. silver and copper). Among these, ITO has found the most across the board use in TCEs. Though, the material has a few disadvantages because of its fragility, high material cost, and the shortage of indium. The brittleness of ITO makes it an especially inadequate choice for flexible electronic applications. In contrast, graphene and CNTs have pulled in noteworthy consideration for their bowing qualities. Unfortunately, these materials additionally show a higher sheet resistance and lower transmittance when contrasted with ITO. To overwhelm these disadvantages, silver and copper nanowires have been recently used to manufacture adaptable TCEs because of the lesser cost, high ductility, and low sheet resistance of the structures. Likewise, the fabricated TCEs utilizing silver and copper nanowires were balanced in the different applications, for example, light emitting diode, touch screen board and solar cell with ease.

Silver nanowire inks with hydroxypropyl methylcellulose (HPMC) binders were coated on polyethylene terephthalate (PET) substrates and welded via flash white light and ultraviolet C (UV-C) irradiation to produce highly conductive transparent electrodes. The coated silver nanowire films were firmly welded and embedded into PET substrate successfully at room temperature and under ambient conditions using an in-house flash white light welding system and UV-C irradiation. A highly conductive and transparent silver nanowire film with excellent reliability could be achieved at room temperature under ambient conditions via the combined flash white light and UV-C irradiation welding process.