Pulsed laser deposition and modification of diamondlike carbon films

Target-plane deposition of diamond-like carbon in pulsed laser ablation of graphite

“…3 also shows that for normal-plane samples, the laser fluence also contributes to the sp 3 content. The effects of laser wavelength and fluence on the sp 3 content are in agreement with other reports [2,3,13]. It is noted that these two laser parameters are closely related to the production of ionized carbon species with sufficient kinetic energy that enables the subplantation formation [12] of DLC.…”

“…For n-PLD, the substrate is placed directly opposing the target or at 908, while for i-PLD the substrate is placed in the same plane as the highly oriented pyrolytic graphite target or at 1808. G-peak usually falls within 1600-1550 cm À1 , and always less than 1600 cm À1 for HOPG, which is typical for the amorphous structure of DLC caused by the presence of sp 3 . The intensity ratio of D:G-peaks, I D /I G which is an extracted ratio of the integrated area under the two curves, qualitatively represents the sp 3 /sp 2 ratio in a DLC sample.…”

“…A low I D /I G ratio indicates high sp 3 content and the reverse is true. However, to be more precise of the amount of sp 3 , it usually requires comparison with more quantitative characterization techniques such as the electron energy loss spectroscopy (EELS) [1,3]. For this work, it is suffix to apply the I D /I G value as an indicator for the study of sp 3 dependence on laser wavelength and fluence, as well as for comparison between the normal-plane sample, target-plane sample, and the ablated area of the graphite target.…”

“…With some optimized parameters, which include the laser wavelength, laser fluence, and high vacuum, the amorphous diamond-like carbon (DLC) thin film is obtained [1][2][3][4][5][6][7]. This deposition arrangement is generally known as the on-axis, or the normal-plane pulsed laser deposition (n-PLD), which usually promise a relatively smooth and particulate-free thin film.…”

Plasma-assisted pulsed laser deposition of carbon films: Effect of oxygen plasma on amorphous carbon film etching

“…The optical band gaps of the films were determined to be in a range of 1.6 -1.8 eV by extrapolation of the plot of (aE) 0.5 (a is the absorption coefficient) as a function of E (Tauc relationship) [13].…”