Laser nanoablation of diamond and formation of atomic-scale surface structures

An experimental study of the mode of multi-pulse (108–109 pulses) laser nanoablation of single-crystal diamond, which is realized at irradiation intensity below the threshold of laser graphitization and allows controlling the depth of laser treatment of this material with accuracy to the atomic layer, has been carried out. The obtained dependences of the nanoablation rate on the laser energy density for various combinations of laser pulse duration and radiation wavelength indicate that the rate of photostimulated oxidation in air atmosphere is determined by the density of laser plasma created inside the material. A consistent decrease in the nanoablation rate with increasing concentration of nitrogen impurity in diamond was found. It was found that the duration of laser etching in the nanoablation mode and, respectively, the maximum depth of the created nanostructures are limited by the effect of cumulative graphitization.