Papers by Keyword: FTIR

Abstract: We discuss several mechanistic approaches and experimental data for improving post-CMP cleaning of W plugs with TiN as barrier liner, and dielectric substrates SiO₂ and Si₃N₄ for use at the 10 nm technology node (metal pitch of 40 nm). Particle charge in the low pH, W CMP slurries are usually positive, and the W surface is always negatively charged at pH >3. Therefore, a strong electrostatic attraction is expected to occur between the W surface and the residual particles during post-CMP cleaning. Two main approaches were chosen to break down the strong particles-W surface post-CMP electrostatic interactions, as well as particles dispersion and prevention of redeposition: (1) using cleaning additives able to adsorb at the W surface and reverse the W surface charge; (2) using organic additives to reverse the particle charge. The latter approach results in two strongly negative charged surfaces, which are able to repulse each other, and leads to the best cleaning.

Abstract: Polymer electrolyte films of poly (vinyl) chloride (PVC) as polymer host doped with ionic liquid 1-butyl-3-methylimidazolium trifluoromethasulfonate (BMIMCF₃SO₃) were prepared by solution cast technique. Ionic conductivity was studied for 95 wt.% and 80 wt.% PVC by using Impedance Spectroscopy (IS). Arrhenius and Vogel-Tamman Fulcher (VTF) behavior were observed before and after T_g of the systems. Fourier Transform Infrared (FTIR) study confirmed that complexation occurred between PVC and BMIMCF₃SO₃.

Abstract: Maleic anhydride grafted natural rubber compatibilizer was prepared in molten state using twin screw extruder. Amount of maleic anhydride and initiator, as well as screw rotation were varied according to Box-Behnken experimental design. Titration of acid group from the anhydride function and FTIR spectra analysis were carried out as quantitative and qualitative analysis of grafted MA, respectively. The results showed that the percentages of grafted MA for all samples were ranged from 1.31 to 5.36%. The optimum conditions are predicted at 14.4 phr of MA level, 0.41 phr of BPO level, and 71 rpm screw rotation giving 5.39 ± 0.16% of grafted MA. FTIR spectra showed that the MA and carbonyl functional group were found in the compatibilizer suggested the presence of grafted MA and ring opening reaction.

Abstract: Development of covalent organic polymer (COP) is a potential new class of adsorbent for gas separation due to their good hydrothermal stability, chemical tuning flexibility and low cost. COP-1 was prepared via one-step polycondensation of cyanuric chloride and piperazine under catalyst free and N₂ atmosphere condition. The properties of COP-1 were characterized using several analytical methods such as Fourier Transform Infra-Red (FTIR), solid Nuclear Magnetic Resonance (s-NMR), Thermal gravimetric analysis (TGA) and N₂ adsorption and desorption measurement. The C-N bond of COP-1 which has non-rigid framework was successfully linked in this study. It is found that COP-1 has low thermal degradation temperature i.e. 483 K. As compared to literature, lower surface area (75.5 m²/g) and slightly large pore size (8 nm) are noticed. The difference of physical properties of COP-1 synthesized between in this study and literature revealed the challenge of reproducibility for COP-1.

Abstract: The behavior and performance of waste cooking oil (WCO) as an additive and replacement of neat bitumen through the modification of asphalt binder is influenced by its chemical structure and composition. Therefore, the identification of chemical composition inside the WCO-modified bitumen should be identified before any modification is taken that later on will affect its performance. Thus, this paper has emphasized and explained about the chemical composition inside modified bitumen by using WCO. The characterization of each chemical element and functional group of WCO-modified bitumen are conducted by using Gas Chromatography-Mass Selective (GC-MS) and Fourier Transform Infrared Spectroscopy (FTIR). GCMS result showed that the presence of Free Fatty Acid (FFA) in WCO while from the FTIR observation, there are same type of functional group existed in all sample which is C-H bond (alkyl). Through the chemical observation conducted, therefore the chemical alteration is required to improve the performance of WCO in modified bitumen in the future.

Abstract: The degradation of polycarbonate (PC) food contact materials was studied based on analysis with GC-MS, FTIR, UV-Vis and TG techniques. It was evident that the processing temperature of the materials significantly enhanced the release of bisphenol A, an endocrine disruptor. Investigation of the redshift of UV band also revealed that high temperatures accelerated the aging degradation of PC.

Abstract: Borate is one of the most popular oxide glass being used in glass research world wide. Due to good reputation, therefore lead sodium borate glasses with compositions (90 - x) B₂O₃ + 10ZnO + xPbO (where = 15, 20, 25, 30 and 35 mol %) have been prepared by using melt-quenching method. In this work, their physical and structural properties with respect to PbO content has been investigated. The densities of these glass samples were increased from 3946.2 kg/m³ to 5107.2 kg/m³ with an increase in PbO concentration. The molar volume are found to vary from 23.78 × 10^-6 m³mol^-1 to 24.39 × 10^-6 m³mol^-1 with respect to PbO content as well. The density and molar volume show inversed result respectively. The FTIR spectral analysis indicates that with the addition of PbO contents in the glass network, structural units of BO₃ are transformed in BO₄. There are no sharp peaks were observed in XRD patterns of the glass samples which confirmed the amorphous nature of the glass. Meanwhile, the micro hardness of these glass samples were also increased from 189 Pa to 355 Pa with increases on PbO content. The results will be discussed and presented in details.

Abstract: Low ionic conductivity and easily attacked by air are among the common issues of lithium salts in lithium based solid electrolytes. Toward this end, our efforts have been focused on the development of a new lithium based electrolyte system which exhibits a good stability against atmosphere and posses high electrical conductivity. Normally, lithium carbonate (Li₂CO₃) alone shows a low electrical conductivity (2×10^-5 Scm^-1). However, the corporation of lithium iodide (LiI) has made a significant impact on the electrical conductivity of the system (4.63×10^-3 Scm^-1). The xLi₂CO₃-yLiI (x = 95-70, y = 5-30 wt.%) solid electrolyte were prepared by mechanical milling technique. The electrical and structural properties of the electrolyte systems were characterized by Electrical Impedance Spectroscopy (EIS) and Fourier Transform Infrared (FTIR) respectively. The highest electrical conductivity (4.6×10^-3 Scm^-1) of the electrolyte system was obtained from the sample containing 20 wt.% of lithium iodide (LiI). The carbonate groups play a role to provide sites for the interaction between interconnected pathways and lithium ions for the fast lithium ion migration.

Abstract: This study was carried out to evaluate the potential of plastic synthesized using bio-based starch. The method began with extraction of starch from chosen tubers with high content of starch; potato and yam. The samples were first grated, grinded and strained to obtain crude starch, which then centrifuged and rinsed to get pure starch. The starch was then reacted with hydrochloric acid to breakdown amylopectin to prevent the starch from becoming plastic-like. Finally, propan-1,2,3-triol was added as a plasticizer to increase the elasticity of the product. The chemical, mechanical, and thermal properties of the products were analyzed using Fourier transform infrared (FTIR), tensile strength tester and Thermogravimetric analysis (TGA). The FTIR spectra of the product displayed the presence of O-H, C-H, C=O and C-O absorption peaks, which indicate the formation of bioplastic has already occured. The tensile strength obtained for potato and yam starch-based bioplastic are 0.6 MPa and 1.9 MPa, respectively. The result gained from TGA showed that 50% weight loss occurred at 250°C for potato and 310°C for yam-based plastic. The highly biodegradability of the plastic was proven using soil burial test, which observed the percentage of soil biodegradation for potato and yam-based bioplastic in 1 week duration is 43% and 26%, respectively. These bio-based plastics have exhibited good thermal and mechanical properties with high biodegradability that makes them a suitable alternative for the existing conventional plastics.

Abstract: Neodymium doped zinc borotellurite glass system were fabricated by using conventional melt-quenching method. The structural properties of the glass system were characterized by using X-ray Diffraction (XRD) method and Fourier Transform analysis (FTIR). The amorphous nature of the glass system was confirmed by using x-ray diffraction method. The transmission band of TeO₃ structural units which indicate the existence of non-bridging oxygen was shown by FTIR analysis. The optical properties of the glass system were determined by using UV-Vis spectrophotometer. Several bands were shown in the absorption spectra which indicate the characteristic of neodymium ions. The obtained values of indirect optical band gap, Eopt lies in the range of 3.151 eV and 3.184 eV.