Advanced screen printing for the fabrication of organic humidity sensors

This paper presents a research focused on development of an advanced screen printing technique for the fabrication of miniaturized, low-cost organic humidity sensors. According to the survey done by BCC Research the segment of temperature and humidity sensors achieved a worldwide turnover of 3.7 billion USD in 2010 and it represented 7 % of global sensor market [1]. Humidity sensors based on organic electronics can be used as diagnostic devices that may be implemented for diverse applications in environmental monitoring, rescue services, health and preventative medical care. The first stage of the research was focused on the advanced screen printing technique development, which could produce line and space widths below 50 μm and ultra-thin layer deposition well below 1 μm, in order to replace expensive and complex vacuum deposition methods and photolithography. The second stage of the research was focused on an organic humidity sensor element fabrication only by the developed screen printing processes. Screen printing is especially suitable due to its simplicity, low-cost, high reproducibility and efficiency in large-scale production.