Effect Of Post-Annealing In Oxygen Environment On Ito Thin Films Deposited Using RF Magnetron Sputtering

This work demonstrated the effect of post-annealing on electrical and optical properties of indium tin oxide (ITO) thin films. ITO with 100 nm thickness successfully deposited using radio frequency (RF) magnetron sputtering in oxygen-free environment on soda-lime glass substrate without substrate heating. Post-annealing treatment was performed on ITO thin films in oxygen environment. Different annealing temperature were studied on the films from 300°C up to 600°C. The annealing time and oxygen flow rate were constant. As the annealing temperature increased, the structure of the thin films changes from amorphous to polycrystalline which lead to the effect of enhanced hall mobility. The optical transmission in visible region strongly related to the annealing temperature. This leads to higher transmittance of ITO thin films and suitable for blue light emitting diode (LED) application. In addition, higher annealing temperature also improves the film electrical properties. Further characterization of the deposited films was done using Hall Effect measurement, UV-Vis spectrophotometer and Atomic Force Microscopic (AFM) to show the improvement on their electrical and optical characteristic. The optical and electrical properties of the films are compared with each other

Corrosion and surface modification on biocompatible metals: A review

Corrosion prevention in biomaterials has become crucial particularly to overcome inflammation and allergic reactions caused by the biomaterials' implants towards the human body. When these metal implants contacted with fluidic environments such as bloodstream and tissue of the body, most of them became mutually highly antagonistic and subsequently promotes corrosion. Biocompatible implants are typically made up of metallic, ceramic, composite and polymers. The present paper specifically focuses on biocompatible metals which favorably used as implants such as 316L stainless steel, cobalt-chromium-molybdenum, pure titanium and titanium-based alloys. This article also takes a close look at the effect of corrosion towards the implant and human body and the mechanism to improve it. Due to this corrosion delinquent, several surface modification techniques have been used to improve the corrosion behavior of biocompatible metals such as deposition of the coating, development of passivation oxide layer and ion beam surface modification. Apart from that, surface texturing methods such as plasma spraying, chemical etching, blasting, electropolishing, and laser treatment which used to improve corrosion behavior are also discussed in detail. Introduction of surface modifications to biocompatible metals is considered as a “best solution” so far to enhanced corrosion resistance performance; besides achieving superior biocompatibility and promoting osseointegration of biocompatible metals and alloys.Universiti Malaysia Pahang fully supports the facilities and resources for this research. The author W.S.W. Harun would like to acknowledge the support of the Qatar National Research Fund NPRP8?876?2?375 (UIC161504), internal grant of Universiti Malaysia Pahang RDU140354, RDU160337, and the support of Research Acculturation Grant Scheme provided by the Ministry of Higher Education, Malaysia RDU151404.Scopu

Surface characterisation and corrosion behaviour of oxide layer for SLMed-316L stainless steel

The stable oxide layer formed through thermal oxidation (TO) process on selective laser melted 316 L stainless steel (SLMed-316 L SS) substrate surface attested to assists in refining their corrosion resistance and observed to behave relatively inert in physiological conditions. The surface characterisation and corrosion behaviour of the oxidised SLMed-316 L SS are the primary focus of this study. The formation of the oxide layer on SLMed-316 L SS was investigated at constant ambient atmosphere and 700 °C temperature for three different soaking times (150, 200 and 250 h). The surface characterisation of the oxide layer was performed using Field Emission Scanning Electron Microscope (FESEM), Energy Dispersive X-ray Spectroscopy (EDX) and X-ray Diffraction (XRD) to correlate the thickness of oxide layer and surface morphology after the TO treatment. Whereas, the electrochemical analysis was conducted using potentiodynamic polarisation to investigate the corrosion behaviour of the oxide layer. The finding disclosed an increase in the oxide layer thickness formation at prolonged exposure in ambient atmosphere. Also, the TO at 150 h showed an improved corrosion behaviour due to the presence of Fe2O3 and Cr2O3 layers. However, the extended soaking time showed no improvement towards the corrosion behaviour