Low Friction-Coefficient TiBCN Nanocomposite Coatings Prepared by Cathode Arc Plasma Deposition

TiBCN nanocomposite coatings were deposited on cemented carbide and Si （100） by a cathode arc plasma system, in which TiB2 cathodes were used in mixture gases of N2 and C2H2. X-ray diffraction shows that TiB2 and Ti2B5 peaks enhance at low flow rates of C2H2, but they shrink when the flow rate is over 200 sccm. An increase of deposition rate was obtained from different TiBCN thicknesses for the same deposition time measured by scanning electron microscopy. Atomic force microscopy shows that the surface roughnesses are -10 nm and ,-20 nm at C2H2 flow rates of 0-100 sccm and of 150-300 sccm, respectively. High resolution transmis- sion electron microscopy and X-ray photoelectron spectroscopy show that the coatings consist of nanocrystal phases Ti2Bh, TiB2 and TiN, and amorphous phase carbon and BN. The average crystal sizes embedded in the amorphous matrices are 200 nm and 10 nm at C2H2 flow rates of 200 sccm and 300 sccm, respectively. In Raman spectra, the D- and G-bands increase with C2H2 flows at low flow rates, but weaken at high flow rates. The microhardness of the coatings decreases from 28.6 GPa to 20 GPa as the C2H2 increases from 0 sccm to 300 sccm, and the ball-on-disk measurement shows a dramatic decrease of the friction coefficient from 0.84 to 0.13. The reason for the reduced hardness and friction coefficient with the change of C2H2 flow rates is discussed.

Influence of N2 flow rate on structure and properties of TiBCN films prepared by multi-cathodic arc ion plating and studied with ion beam scattering spectroscopy

TiBCN films were deposited on Si(100) and cemented carbide substrates by using multi-cathodic arc ion plating in C_2H_2 and N_2atmosp^here. Their structure and mechanical properties were studied systematically under different N_2 flow rates. The results showed that the Ti BCN films were adhered well to the substrates. Rutherford backscattering sp^ectroscopy was employed to determine the relative concentration of Ti, B, C and N in the films.The chemical bonding states of the films were explored by X-ray photoelectron sp^ectroscopy, revealing the presence of bonds of Ti N, Ti(C,N), BN, pure B, sp^2C–C and sp^3C–C, which changed with the N_2 flow rate. Ti BCN films contain nanocrystals of Ti N/Ti CN and Ti B_2/Ti(B,C)embedded in an amorphous matrix consisting of amorphous BN and carbon at N_2 flow rate of up to 250 sccm.

Study of doping uniformity of a 200 kV ion implanter by RBS and sheet resistance measurements

The ion implantation uniformity is of vital importance for an ion implanter.In this paper,we report the,uniformity measurement for a large current ion implanter(LC-16 type) by implanting of 190-keV Ar ions into Si to 3×1016 atoms/cm2,followed by Rutherford backscattering spectroscopy(RBS) and sheet resistance measurement providing quantitative information on spatial distribution of dopants.The implant doses obtained from RBS at selected points of the sample give a spatial uniformity of <5%,which are confirmed by the sheet resistance measurement.While sheet resistance is an indirect method for dose evaluation of ion-implanted samples,RBS provides a competent technique for calibration of the ion implantation system.And both measurements show that good uniformity can be achieved for the ion implanter by tuning of the scanning process.