Pulsed laser deposition of diamond from graphite targets

Abstract

Diamond crystals of 1 μm mean size were grown on (100) silicon substrates by ArF (193 nm) laser ablation of graphite in a hydrogen atmosphere with a laser power density of 1.3×108 W/cm2 at relatively low substrate temperature (450 °C). Raman spectroscopy analysis confirmed the diamond cubic structure of the crystals by the presence of a sharp peak at 1332 cm−1. When a KrF (248 nm) laser was used instead of the ArF no diamond phases were detected in the deposited films and the Raman spectra showed only the two bands centered at 1340 and 1600 cm−1 characteristic of amorphous carbon. The results demonstrated that the laser wavelength is a determinant parameter in the growth of diamond by laser ablation of graphite.

Laser ablation in liquids: Applications in the synthesis of nanocrystals

“…Particularly, the deposition of amorphous carbon films with diamond-like characters has been widely reported by laser ablation of graphite in vacuum [214][215][216][217][218][219][220][221][222][223][224][225][226][227], in which some researchers reported the growth of crystalline particles, but the lack of a diamond peak in Raman spectra was a common result in all reports. It was not until in 1995 that Polo and co-workers [228] first showed the Raman spectroscopy analysis of the sample that is confirmed to have diamond cubic structure of the crystals by the presence of a sharp peak at 1332 cm À1 . In 1992, Ogale and co-workers [19] first reported that diamond particulates with cubic structure were detected from the production of pulsed ruby laser irradiation of the pyrolytic graphite target in the benzene solution.…”

Micro-Raman spectroscopy of the solid state: applications to semiconductors and thin films

“…I I O of these precursors, which often consists in small individual grains, allows to know if the processing conditions are correct or should be changed [37][38]. For example, the Raman spectrum of a single micro-crystal of figure 6(a) corresponds to that of a high quality diamond crystal whereas the spectrum of the thin film, shown in figure 6(b), indicates in addition of sp 3 carbons some degree of disorder and graphitic structures.…”

Epitaxial diamond growth on sapphire in an oxidizing environment

“…The film growth rate can be controlled by changing the UV laser pulse frequency. Some attempts to grow diamond by pulsed laser deposition using graphite targets in a hydrogen atmosphere have been reported 16,17 . Here we examined the possibility of hydrogen-free growth of diamond films on sapphire substrates by the pulsed laser deposition process using a graphite target under a partial pressure of oxygen.…”