UV picosecond laser-induced changes on chemical vapor deposited diamond surface investigated by photoelectric charge measurements and surface analysis

In this paper, we investigate UV picosecond laser-induced effects on undoped chemical vapor deposited (CVD) diamond surfaces as a function of irradiation time. Diamond films are negative electron affinity (NEA) emitters and contain defects (non-diamond phases). Surface analysis is performed before and after laser irradiation, in order to clearly demonstrate surface structural transformations. A diamond peak shift after pulsed laser irradiation is determined by micro-Raman analysis and correlated to stress variations in diamond. The post-irradiated diamond surface reactivity with ambient air is studied by X-ray photoelectron spectroscopy (XPS). XPS results show surface bonding modifications due to carbon–oxygen interaction enhanced by UV pulsed laser irradiation.