Fig. 3: Surface characterization before and after laser activation.

a Corresponding intensity sputter profiles of positive ions prior to laser activation and following laser activation measured by TOF-SIMS. b Mass spectrum obtained by TOF-SIMS of the surface before and after laser activation. c Micro-Raman spectra of the surface before and after laser activation. d XPS survey spectra of the surface after laser activation. e Cu 2p XPS spectra of the surface after laser activation