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Yttria stabilized zirconia thin films have been deposited by RF plasma enhanced MOCVD technique on silicon substrates at substrate temperature of 400 °C. Plasma of precursor vapors of (2,7,7-trimethyl-3,5-octanedionate) yttrium (known as Y(tod) 3 ), (2,7,7-trimethyl-3,5-octanedionate) zirconium (known as Zr(tod) 4 ), oxygen and argon gases is used for deposition. To the best of our knowledge, plasma assisted MOCVD of YSZ films using octanediaonate precursors have not been reported in the literature so far. The deposited films have been characterized by GIXRD, FTIR, XPS, FESEM, AFM, XANES, EXAFS, EDAX and spectroscopic ellipsometry. Thickness of the films has been measured by stylus profilometer while tribological property measurement has been done to study mechanical behavior of the coatings. Characterization by different techniques indicates that properties of the films are dependent on the yttria content as well as on the structure of the films. [ABSTRACT FROM AUTHOR]

Highlights: [•] Yttrium oxide thin films are deposited by RF Plasma MOCVD Process using Y(thd)3 precursor. [•] Films are deposited under varying influence of RF self-bias on the substrates during deposition (−50V to −175V). [•] It is possible to deposit single phase cubic Y2O3 films at low substrate temperature. [•] RF bias on substrate controls the texture of deposited film. [•] To the best of our knowledge, so far there is no reported study on the effect of RF substrate bias on properties of films. [ABSTRACT FROM AUTHOR]

SiO x containing diamond-like carbon (DLC) films are deposited on the stainless steel 316 substrates by radio frequency (r.f.) plasma assisted chemical vapor deposition (PACVD) process using plasma of Argon, methane gases and Hexamethyl Disiloxane vapors. The sp 3 /sp 2 ratio of carbon bonding in the films is found to increase with increase in bias. Films deposited at low bias voltage (-25 V) show onset of film spallation and critical failure during scratch test at low progressive load and it has high friction coefficient. In contrast, film deposited at −100 V bias shows low coefficient of friction <0.05. Such a low friction coefficient is related to optimum fraction of sp 2 carbon bonding and a-C contents. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) have been directly grown on Inconel 600 substrates by microwave plasma enhanced chemical vapor deposition without using any external catalyst. Grown CNTs were characterized by field emission scanning electron microscopy, high resolution transmission electron microscopy, X-ray diffraction, Raman spectroscopy and field emission measurements. Characterization results show that field emission current density increases from 200 μA/cm 2 at ∼5.5 V/μm to 14.5 mA/cm 2 at ∼1.6 V/μA when substrate is heat-treated and incident microwave is attenuated before reaching it. Detailed characterization reveals that heat-treatment results in migration of Cr and Fe oxides towards the top surface which completely changes substrate morphology also. Microwave attenuation reduces reflection of microwaves from the substrate and increases residence time of the precursor over the substrate promoting high density growth of CNTs. The combination of these two process parameters resulted in growth of long, dense CNTs with bamboo-like defects that contributes to enhanced current density at lower applied field. [ABSTRACT FROM AUTHOR]