X-ray-induced Cu deposition and patterning on insulators at room temperature

X-ray irradiation is shown to trigger the deposition of Cu from solution, at room temperature, on a wide variety of insulating substrates: glass, passivated Si, TiN/Ti/SiO₂/Si and photoresists like PMMA and SU-8. The process is suitable for patterning and the products can be used as seeds for electroplating of thicker overlayers.