Branko Tomcik

University of Belgrade · Institute for Physics

Capabilities of the rf plasma beam source in deposition of ultra thin diamond like carbon for the hard disk drive applications have been studied. Nano-sized films were doped by nitrogen, hydrogen and silicon and characterized by micro Raman spectroscopy. Projected ranges of incident carbon ions into the magnetic layer as well as growing film were c...

Amorphous hydrogenated and/or nitrogenated carbon films, a-C:H/a-C:N, in overall thickness up to 2 nm are materials of choice as a mechanical and corrosion protection layer of the magnetic media in modern hard disk drive disks. In order to obtain high density and void-free films the sputtering technology has been replaced by different plasma and io...

Nano sized diamond-like carbon (DLC) films doped with nitrogen and hydrogen are materials of choice as a mechanical and corrosion protection barrier for mag-netic layer of the computer hard disks. Overall thickness of a-C:N/a-C:H layer is bellow 2 nm and is usually accompanied by 0.5 nm thin flash layer of Cr. To obtain dense and void-free DLC film...

Air humidity as well as various gases present in the environment or evolved from the hard disk file has a detrimental effect on the lifetime of the hard disk. The corrosion properties of unprotected Co Cr Pt magnetic layer and covered by a carbon 78 12 10 overcoat have been studied using a three-electrode electrochemical corrosion test. Potentiodyn...

For high density magnetic recording, it is necessary to protect the magnetic layer from wear and corrosion with a thin carbon overcoat. On ultrasmooth disk substrates, magnetron sputtering is still the preferred technique because it can provide protective carbon layers as thin as 4 nm. Degradation of the magnetic layer occurs in the atmosphere and...

With the trend of decreasing the thickness of the carbon overcoat on high-density magnetic recordings, the corrosion properties of a hard disk multilayer structure are becoming a hot issue. An ideal overcoat would be uniform across the disk's surface, have low porosity and electrical conductivity as well as being impermeable to water. However, in r...

The change in the water contact angle for poly(ether ether ketone), polycarbonate and poly (methyl methacrylate) with treatment time in microwave oxygen plasma is discussed as well as the aging properties of the plasma treated polymers. XPS and the micro-Raman technique were employed to provide data on the extent of surface oxidation of polypropyle...

A series of dc sputter deposited amorphous carbon nitride films were characterized by micro-Raman spectroscopy. Films were deposited on silicon, CoCrPt/CrV/glass and a CoCrPtTa/CrV/glass substrate. A direct correlation was found between the nitrogen content in a film, measured by Rutherford backscattering spectroscopy, and the Raman C�N peak intens...

A magnetic layer based on Co-alloys does not possess the necessary mechanical durability and corrosion resistance and must be covered with a protective layer. An accelerated electrochemical test has been conducted on a hard disk magnetic layer covered with amorphous hydrogenated carbon doped with nitrogen. From the potentiodynamic and DC polarizati...

A method for quantitative analysis of hydrogen distribution in 3D has been developed using the elastic recoil detection analysis (ERDA) technique in conjunction with a nuclear microprobe. 2–3 MeV alpha particles, focused down to 2–5 μm, were applied at incident angles of 10–15° to the sample surface. Using an absorber placed in front of surface bar...

Spatial distribution of the deposition rate of diamond-like thin films inside a r.f. discharge was studied experimentally. A thin optical fiber was inserted along the axis of the discharge which made negligible perturbation on the discharge itself. Deposited film thickness along the fiber was determined by using a scanning electron microscope and u...

In this paper we analyze application of a simple microwave cavity discharge on the surface modification of polymers. Electrons and radicals from the low pressure plasma as well as the metastable excited oxygen species react intensively with many engineering plastic materials leading to the increased adhesion of polymers. This is of importance to ac...

In order to determine the mechanism of diamond-like film deposition in a r.f. discharge in methane, a tiny glass fiber was spanned along the discharge axis and perpendicular to the parallel-plate electrodes. The discharge was operated in a symmetric and slightly asymmetric regime. The film thickness and its surface topography were analyzed by means...

A novel rf plasma beam source operated with CH4 and CH4+H2 mixtures is used for the formation of hydrogenated hard carbon layers. The film composition, particularly the H content, is determined by secondary neutral mass spectrometry (SNMS) and the binding structure by XPS utilizing the characteristic plasmon losses of the C(1s) photoelectrons. As d...

In this paper we present experimental results obtained for a rf discharge in SF 6 and for SF 6 with Ar and/or N 2 . The data for power dependence of some emission lines usually used in actinometry are acquired and their applicability and excitation kinetics discussed. We also present the spatial (time averaged) variations of some emission lines. Fr...

The processes at the anode of H2-N2 glow discharge have been investigated. By varying process parameters such as gas composition, the anode temperature, treatment time, and polarization of samples, different surface properties of anode material have been obtained. The anode was made of different materials. The structure of the nitrided layer has be...