Qualification of silver nanowire transparent conductive films for touch panel applications

Transparent conductive films have become a ubiquitous component of electronic devices ranging from capacitive touch screens in smartphones, tablets, and larger display devices to transparent electrodes in organic light emitting diodes and photovoltaic cells. Indium Tin Oxide (ITO) is the most established transparent conductive film in the market, but has inherent drawbacks because it is a brittle ceramic deposited on plastic. Carestream has developed a silver nanowire transparent conductive film, FLEXX™, that is solution-coated in a continuous roll-to-roll process. For various alternatives to ITO, one of the key potential challenges is in providing sufficient environmental stability needed to ensure a robust product. This paper elucidates the qualification of silver nanowire transparent conductors into touch panel environments that include high temperature, high humidity, exposure to visible and ultraviolet light, thermal cycling, non-operating thermal shock, and electrolytic electromigration test conditions. For the first time it is shown that silver nanowire transparent conductors can survive all such environments and are suitable for manufacturing scale-up into commercial products.