Highly Stretchable LED Display Using Liquid Metal and Molybdenum-Barriered Multilayer Electrodes with Long-Term Reliability

Promising freeform deformable displays require highly stretchable interconnection lines and reliable, low-resistance connections. To this end, a stretchable light-emitting diode (LED) display with a molybdenum-barriered multilayer electrode using liquid metal (LM) alloys with high reliability and stretchability under repeated deformations of 12 000 times and long-term stability over 300 days is introduced. The developed multilayer-stacked electrode shows consistent and stable stretchable electrical connections with long-term reliability, even under continuous mechanical deformation. Thus, the developed display with micro- or mini-LED components can be deformed, such as domes and twice folding like a handkerchief. Highly stretchable LM fine lines are developed by printing directly onto the acrylic adhesive layer, which enables high stretchability even under 100% uniaxial strain with a 100 µm narrow width. The stretchable display technology has successfully realized form-free displays that flexibly deform into 3D shapes for advanced wearable and freeform applications.