Optimizing Local Conductivity in Printed Electronics: A Laser-
Controlled Approach

In the era of digitalization and Industry 4.0, sensor technology is pivotal for real-time
monitoring and data collection, significantly impacting product life cycle management.
Traditional strain gages are produced via complex lithographic processes and require
manual bonding, leading to potential quality inconsistencies affecting data accuracy.
Direct application through digital printing offers a promising alternative, aiming to reduce
production costs while enhancing quality assurance.
Printed electronics require the ink to be sintered for conductivity, with most processes
striving for maximum conductivity. However, the printing process often results in
inconsistent local conductivity, impairing sensor performance. Laser technology provides
a solution by enabling precise control over the local sintering degree, thus optimizing
conductivity. Initially, low-power sintering is applied, followed by conductivity
measurement, potentially through contactless THz radiation. Local conductivity variations
due to printing inconsistencies are then addressed with a second sintering step to
standardize and improve sensor quality.
This study explores the impact of laser parameters on the local conductivity of thin silver
layers during both sintering steps, identifying defect sources and achieving resistance
fluctuations below 1 Ω. This method aims to fulfill stringent commercial strain gauge
sensor requirements.