Printed & flexible electronics: status, innovations and prospects

All are produced using printed and flexible electronics, an alternative approach to conventional printed circuit boards that combines additive manufacturing with flexible substrates. Bringing benefits such as rapid prototyping, improved sustainability, scope for form factor differentiation and even stretchability, printed & flexible electronics is gaining traction across an extremely diverse range of applications.

Dr Matthew Dyson, Principal Technology Analyst at IDTechEx further explores.

IDTechEx’s new report ‘Flexible & Printed Electronics 2023-2033: Forecasts, Technologies, Markets’ provides a comprehensive overview of what can seem a bewilderingly broad topic. The report outlines innovations, opportunities, and trends across five sectors of the printed and flexible electronics market: automotive, consumer goods, energy, healthcare/wellness, and infrastructure/buildings/industrial. This analysis includes granular forecasts of 50 distinct applications and 40 detailed company profiles.

Additionally, the report outlines developments across multiple underlying technologies: six distinct manufacturing modalities (including in-mould electronics and flexible hybrid electronics), five material types (including conductive inks and component attachment materials), and four component types (including flexible ICs). Multiple recent examples, acquired from interviews and industry conferences, show technology development directions and successful commercialisation. Assessments of technological and commercial readiness, along with additional forecasts for manufacturing methods and conductive inks, are also included.

Application opportunities

As with conventional PCBs, printed and flexible electronics has applications across most market verticals. For example, electronic skin patches utilising conductive inks for electrodes and contacts are already available, as are printed pressure-sensitive insoles for gait monitoring. Conformality lends itself to automotive interiors, where printed/flexible electronics is utilised for lighting, heating, and touch-sensitive interfaces. Organic photovoltaics is seeing a renaissance, with recent commercial examples including both building integration and indoor energy harvesting. Sensors based on printed electronics for asset tracking and preventative maintenance promise low production costs novel form factors to suit specific requirements.

Innovations

Printed and flexible electronics represents a fundamentally different approach to manufacturing, replacing subtractive removal of laminated copper with additive deposition of conductive ink. This reduces waste and facilitates digital manufacturing with the associated benefits of rapid prototyping and straightforward design adjustments. The report evaluates a range of manufacturing innovations and their prospects, ranging from fully additive 3D electronics to in-mould electronics and emerging digital printing methods with resolutions as small as 1μm.

Material innovations underpin many emerging hardware technologies, and printed electronics is no exception. Conductive inks underpin the technology, with dozens of companies developing inks with a range of compositions and attributes. Viscous silver-flake-based ink for screen printing dominates, but alternatives such as nano-particle and particle-free inks are gaining traction for specific applications such as EMI shielding. An especially notable trend is the development of copper ink, which promises a substantial cost reduction over its silver counterparts. Other specialised materials include ultra-low temperature solder and field-aligned anisotropic conductive adhesives enable components such as LEDs to be securely attached to cheaper, thermally fragile substrates. Furthermore, many sensors require specialist materials, such as printable piezoelectric polymers for vibration sensing and functionalised carbon nanotubes for ion detection.

While the original vision for printed and flexible electronics was to print every aspect of the circuit, including the integrated circuit, this has largely been supplanted by flexible hybrid electronics (FHE), which combines printed and mounted functionality. As such, there is an opportunity for natively flexible integrated circuits, batteries, and displays.