Researchers from the Massachusetts Institute of Technology (MIT) have shown off a new approach to building high-precision flexible electronic circuit boards with embedded functional devices — using lasers.
“We introduce E-LIG, a laser-enabled, additive fabrication method for flexible, double-sided printed circuit boards (PCBs) with integrated functional devices,” corresponding and first author Wedyan Babatain explains of the team’s work. “E-LIG combines laser-induced graphene (LIG) patterning with copper electroplating to create high-resolution circuits directly on flexible and transparent substrates. We demonstrate circuits with embedded sensors and actuators on a single substrate, showing the method’s scalability, and suitability for applications in wearables, soft robotics, and interactive surfaces.”
Researchers have shown a way to easily make functional flexible electronics with a laser-based additive manufacturing process. (📷: Babatain et al)
The E-LIG approach uses lasers for additive, rather than subtractive, manufacturing process through what is known as selective copper electrodeposition — blasting the target with a carbon dioxide laser to form a conductive graphitic layer to as a surface for adding copper to, rather than taking it away, from the circuit substrate. This, the team says, can be applied to a range of substrate types, including soft and flexible substrates, and scales up to 100cm². More importantly, it allows for the direct integration of functional devices.
“Functional LIG device integration, including sensors and actuators, directly interfaced with control circuits on a single substrate is demonstrated,” Babatain explains. “Applications such as real-time graphical output and interactive interfacing showcase the method’s versatility. E-LIG exhibits repairability for on-demand restoration of damaged circuits, enhancing durability and offering a scalable, cost-effective solution for multifunctional printed electronics.”
The team’s prototypes include a strain sensor, a pressure sensor, a heater, and even an actuator that bends when voltage is applied. (📷: Babatain et al)
To prove the concept, the team built a range of prototype devices: a printed current-limiting resistor for an LED, a flexible strain sensor for use with a Microchip SAMD11 microcontroller, a pressure sensing system, a heater, and a electrothermal actuator capable of bending in response to applied voltage. “These applications highlight the versatility of the developed process,” the team claims, “and its potential to advance multifunctional printed electronics.”
The team’s work has been published in the journal Advanced Science under open-access terms; more information is available on the project website.
Main article image courtesy of Wedyan Babatain.
