Pulsed laser deposition of diamond-like carbon films

Abstract

Carbon thin films have been prepared by 248 nm excimer laser vaporization of graphite targets. The effect of a variety of process parameters on the film properties is investigated. Deposition at or below room temperature yields diamond-like films with low hydrogen content, high optical transmission, and high resistivity. Electron energy loss spectra indicate sp3 bond fractions of 70–85%. Detailed analyses of the pseudodielectric functions, measured using spectroscopic ellipsometry, show the films to have normal dispersion and an index of refraction of 2.5 in the visible wavelength region. The effects of a low pressure hydrogen background and the use of auxiliary pulsed and dc plasma enhancements are also examined.

Optical emission spectroscopic study of plasma plumes generated by IR CO2pulsed laser on carbon targets

“…These results are consistent with earlier reports on vibrational temperature by different authors [11,13,18,20,22,28,30]. It has been observed [7] that the degree of the diamond-like character in DLC films varies due to different temperatures in the laserinduced plasma. This can be due to the fact that the sp 3 fraction in deposited films increases when the energy of the particles increases.…”

“…Pulsed laser ablation (PLA) provides a means of depositing thin coatings, of a wide range of target materials, on a wide range of substrates, at room temperature. Diamondlike carbon (DLC) thin films have attracted a considerable amount of scientific interest in the field of electronic research due to their outstanding properties, such as high hardness, chemical inertness, high thermal conductivity, high electrical resistivity and optical transparency from UV to IR [7]. For the production of high-quality DLC films through PLA, it is necessary to understand the formation of atomic and molecular species and their dependence on various parameters such as the laser power density, pressure of the boundary ambient atmosphere, concentration of the species at different distances from the target and so forth.…”

Élaboration de couches minces de carbone par ablation laser femtoseconde pour application aux biomatériaux implantables

“…La spectroscopie NEXAFS (Near Edge X-ray Absorption Fine Structure) réalisée sur les dépôts obtenusà différentes fluences laser permet de remonter au taux d'hybridation sp 3 des atomes de carbone par intégration des pics *sp 2 et * sp 3 du graphite et du diamant respectivement [9][10][11]. La fluence laser, dans la gammeétudiée, ne semble pas affecter de manière significative la nature du DLC en terme d'hybridation du carbone.…”

Influence of krypton atoms on the structure of hydrogenated amorphous carbon deposited by plasma enhanced chemical vapor deposition

“…19 The hardest known intrinsic a-C, the so called tetrahedral amorphous carbon ͑ta-C͒, is commonly deposited by filtered cathodic vacuum arc ͑FCVA͒, [20][21][22][23][24] mass selected ion beam, 25 or pulsed laser deposition. [26][27][28] Investigation concerning the incorporation of noble gases in carbon structures have many purposes, such as to understand the origin of noble gases in meteorites 29,30 or to understand the mechanisms behind the changes of the properties ͑stress, friction coefficient, hydrofobicity, etc.͒ of amorphous carbon films. Among these procedures, the insertion of noble gases into amorphous carbon have been investigated either through the bombardment of the film by noble gases, using an ion gun, or introducing noble gases in the atmosphere during deposition by PECVD.…”