All-surface carbon circuitry enabled by ultrafast laser chemical vapor deposition

Abstract Creating arbitrary-shaped 3D electrodes on all surfaces of electronic structures holds critical significance in semiconductor packaging, micro-displays and bio/chemical sensors for more precise, more reliable and higher density integration. Multi-step nature of the existing electronics patterning technologies, however, translates to increased cost and process complexity together with low design flexibility. Here, we introduce an ultrafast-laser-driven conductive thin-film deposition technique, enabling sub-micron-resolution patterning of conductive carbon electronics on all substrate surfaces. This method leverages the nonlinear absorption of ultrashort laser pulses, not to directly decompose the precursor, but to locally heat transparent quartz substrates. This localized, intense heating then triggers the decomposition of a gaseous precursor on the hot substrate surface, leading to the direct formation of laser-induced graphene (LIG). We demonstrate the ability to achieve tunable LIG morphology and electrical properties, including low sheet resistance, by precisely controlling laser parameters and reaction conditions. Crucially, this technique allows for the creation of intricate three-dimensional conductive patterns within transparent structures, opening up new avenues for the direct fabrication of integrated electronic components. This versatile approach holds significant promise for advanced applications in semiconductors, sensors, biotechnology, and microfluidics, offering a pathway to create functional electronic architectures with unprecedented spatial control in transparent structures.