Advanced materials and technologies for the sustainable printed electronics on glass

Transparent electronic devices rely on a transparent conductive material (TCM) to function. The growing demand for such devices is driving the growth of the TCM segment. The market s state-of-the-art TCM is indium tin oxide (ITO) with a sheet resistance of ∼10 Ohm/sq and an optical transmittance about 90 %. Sputtering is the most commonly used process for ITO in commercial applications. However, the scarcity, toxicity, and high cost of indium oxide, as well as the expensive vacuum-based physical deposition methods, make it necessary to replace indium oxide in mass production with a more economical material and processing method. In the field of glass packaging, there is an urgent need for indium-free materials and solution-based technologies for economic TCM processing on industrial glass products and in mass production. In the proposed project we will realise an electrode with high optical transmission and low sheet resistance, similar to the conventional ITO, on an industrial glass product for next-generation transparent electronics. The realisation of indium-free TCM from solutions on industrial glass is a breakthrough in transparent electronics: it is a low-cost, environmentally friendly industrial process that enables the integration of electronics directly into industrial glass products. It represents a new paradigm for smart glass packaging that significantly increases the company's competitiveness in the global market and attracts new customers. The objectives of the project are: 1) Lab-scale fabrication of TCM on flat and smooth glass from solutions by spin coating, screen printing and inkjet printing and post-deposition curing. The goal is to process TCM with a high optical transmission over 90 % and a low Rs below 500 Ohm/sq; 2) Pre-treatment of industrial glass products (bottle) with the objective of achieving surface dimensional homogeny under 2 % and surface roughness below 50 nm and ensuring the deposition of TCM solutions; 3) Deposition of TCM solution on industrial glass in an industry-relevant environment and validation of TCM thin films within the electrochromic test device. Assessment and evaluation of the technological, economic and environmental impacts of TCM in comparison to the competitive market solutions and state of the art. To achieve these objectives, we will design and develop metal oxide, indium-free solutions with properties suitable for spin coating, inkjet printing and screen printing. These technologies will be utilised for TCM processing on flat and smooth glass and optimised to obtain the targeted properties of the TCM. One technology, selected based on the best properties of the TCM, will be utilised for the lab-scale processing of TCM on pre-treated industrial glass to obtain a thickness-uniform, homogeneous layer with reproducible properties, high optical transmission and low sheet resistance. The TCM will be validated based on the properties of an electrochromic device. After optimisation of the procedures, TCM will be manufactured on a pre-treated industrial glass in large-scale production and the production costs will be compared to established production process in RC eNeM based on a metal-based electrode. The project is divided into six inter-related work packages: 1) Transparent conductive electrode (TCE) on laboratory glass, 2) TCE on industrial glass, 3) Feasibility test, 4) Technology validation and industrial assessment 5) Characterisation and 6) Management. The equipment for the realisation of the project is available at the Jožef Stefan Institute, the National institute of Chemistry and RC eNeM, which are the partners in the proposed project.