Satreerat K. Hodak

Growth of (Zr,Ti)N Thin Films by Ion-Assisted Dual D.C. Reactive Magnetron Sputtering

The ternary nitride (Zr,Ti)N thin films were grown on silicon substrates by ion-assisted dual d.c. reactive magnetron sputtering technique. The substrates were exposed to ion bombardment with varying kinetic energy in the range of 3-103 eV under N/Ar ratio of 1:3. The (Zr0.6Ti0.4)N was formed at all growth conditions. X-ray diffraction measurement indicates the presence of (Zr,Ti)N solid solution with (111) and (200) preferred orientations. The (200) orientation is only present when the films are grown at ion bombardment energies higher than 33 eV. Optimum conditions for film growth produced hardness in the range of 27-29 GPa.

Etching Effect of SF6 Plasma on Cotton Fiber

The plasma treatment of cotton was performed by the inductively coupled 13.56 MHz RF plasma reactor. The samples were treated with sulfur hexafluoride (SF6) plasma under different power, pressure and exposure time conditions. The morphology change, the weight loss and the reduction in tensile strength of cotton fabrics were strongly related to the etching effect of the SF6 plasma. The exposure time plays an important role in the change of mechanical strength of the fabric while the operating pressure imparts less prominent effects. Prolonged plasma process beyond 5 min or at high plasma operating pressure above 0.5 torr revealed significant damage to the cotton fiber. However, dramatic surface morphology change was not observed on cotton fiber having less than 2% weight loss after plasma treatment.

Synthesis and Characterizations of Strontium Substituted Hydroxyapatite Thin Films

Strontium substituted hydroxyapatite(SrHAp) were fabricated both in the form of powder as reference and thin film by using inorganic precursor reaction. The sol-gel process has been used for the deposition of SrHAp layer on stainless steal 316L substrate by spin coating technique, after that the films were annealed in air at various temperatures. The chemical composition of SrHAp is represented (SrxCa1-x)5(PO4)3OH, where x is equal to 0, 0.5 and 1.0. Investigations of the phase structure of SrHAp were carried out by using X-ray diffraction technique (XRD). The results showed that strontium is incorporated into hydroxyapatite where its substitution for calcium increases in the lattice parameters, and Sr3(PO4)2 can be detected at 900°C. The SEM micrographs showed that SrHAp films exhibited porous structure before develop to a cross-linking structure.