Papers by Keyword: SAM

Abstract: In semiconductor device manufacturing, it is often necessary to process devices that incorporate both Si₃N₄ and SiO₂ with etching solutions. Recently, we found that a cellulose-based polymer (DC01) selectively adsorbs onto silicon nitride and acts as a protective film against etching with buffered fluoric acid. However, the mechanism behind this selective adsorption remains unclear, and a protective film persists after etching. QCM measurements and calculations of the surface free energy indicate that the affinity between DC01 and Si₃N₄ was significantly stronger than that of SiO₂. Notably, the same behavior was not observed with cellulose or cellulose acetate, indicating that this phenomenon is unique to our original cellulose. Additionally, we successfully prepared films using a facile dipping method. Furthermore, we discovered that the strongly adhesive DC01 film can be completely removed by subjecting it to oxidative conditions, such as SC-1 or SC-2.

Abstract: New treatments for replacement of chromate require lower toxicity and corrosion protection. This study aims to investigate the influence of the combination of a Ce conversion coating (CCCe) with glycol molecules on the corrosion resistance of the AA2024-T3 clad (AA1230). The corrosion resistance of surface treated and untreated samples was evaluated by electrochemical techniques (electrochemical impedance spectroscopy, polarization tests and open circuit potential). These tests were complemented by salt spray tests to accelerate the corrosive effects of weathering. The surfaces were analyzed after corrosion tests by scanning electron microscopy with X-ray energy dispersive detector (SEM - EDX). The results of the CCCe samples in combination with glycol were compared with that of the surface with chromate layer and the results showed that the CCCe treatment is a candidate for replacement of chromating with the advantage that it does not generate toxic residues. The self-healing capacity of the new treatment tested was indicated by the increased formation of corrosion products deposition on top of Fe rich intermetallis in the AA1230 clad with time of exposure to the electrolyte.

Abstract: In order to improve the anti-corrosion characteristic of Ag-coated 316SS bipolar plates in PEMFC environment, self-assembled monolayer (SAM) was prepared on its surface by chemical methods. The electrochemical characteristic of modified bipolar plate was also investigated. The results indicated that the SAM was composed of dodecyl thioalcohol. After forming SAM, the bipolar plate’s contact angle increased from 58° to 102°. In addition, its double layer capacitance (Cd) was decreased and charge transfer resistance was increased. The homogeneous SAM, which acted as a protective barrier, inhibited the corrosive ion from corroding. SAM may provide significant protection against corrosion in PEMFC environment.

Abstract: This paper compares two kinds of Marshalling station integrated automation systems: SAM and CIPS, combining with the practical condition of Zhengzhou north station, analyzing from various angles such as safety and efficiency, finally choose the appropriate solution. In doing this, it will help to provide a strong support for the safe production and efficient transportation of Zhengzhou North Station.

Abstract: Self-assembled monolayer (SAM) was adsorbed on the surface of vanadate conversion coated AZ31 magnesium alloy. The SAM thin film was deposited using (Tridecafluoro-1, 1, 2, 2-tetrahydrooctyl) trimethoxysilane (FAS13) and Tetrakis (trimethylsiloxy) titanium as a catalyst. Contact angles measurement, SEM, XRD, EDS and XPS were employed to analyze the surface morphologies, molecular composition, phase structure and wettability of the coatings formed on Mg alloy substrate. Corrosion resistance property of the coatings was also examined using the anodic polarization method and salt spray test. The anticorrosion property was improved with SAM post treatment. Furthermore, the contact angle increases from 12 deg. to 165 deg. indicating to production of super hydrophobic surface with SAM post treatment.

Abstract: The rapid development of the resource-based economy causes many environment problems. Some environmental policies are thought to be more effective than other tools for solving those problems. The paper established Social Accounting Matrix from Inner Mongolia's statistic data and Input-Output table of 2007. The CGE model simulated the effects of environmental policies on energy saving, emission reduction and different industries. The result shows that increases of 10% and 20% in resource tax rates have negative effects on the local economy, but positive effects on energy intensity and pollution emission. Moderate increase in energy price and pollutant discharge fee has negative impacts on the local economy with different extents. Increase in energy price has significant negative effects on the local economy, but prominent positive effects on pollution emission and energy intensity. So the best policy option should be to increase either resource tax or pollutant discharge fee, or both.

Abstract: Thermo-mechanical failure is the main factor to impact the microelectronic packaging reliability. Under thermal loads, the microelectronic packaging is easy to produce cracks, delamination, voids, and other defects, which can emerge and grow under thermo-mechanical stresse caused by the different coefficients of thermal expansion (CTE). Firstly, a geometric model of Plastic Leaded Chip Carrier (PLCC) packaging was established and the thermo-mechanical property of PLCC packaging was analyzed using finite element analysis (FEA) software ANSYS. Then, the thermal cycling test on a set of PLCC packaging was conducted according to the MIL-STD-883H Microcircuits Test Method Standard with temperature range from-65°C to 150°C, and the crack growth rate of PLCC packaging was studied experimentally using Scanning Acoustic Microscopy (SAM). Finally, the Anand model was adopted to predict thermal fatigue life, which was consistent with the experimental results. With these researches, the thermo-mechanical reliability evaluation of the PLCC packaging was investigated using finite element analysis (FEA) combined with analytical methods.

Abstract: 3Dimensional Integration can solve many challenges which are being faced by modern planer integration. The major bottleneck of 3D-Integration are contamination and Copper surface oxidation which is the cause of the requirement of high temperature while bonding. Reduction of this high bonding temperature is the key challenge of 3Dimensional Integration. In this research work we investigate and compare the Copper surface protection characteristic of Self-Assembled Monolayer (SAM) of Alkyl Thiol having different Carbon chains (C₆,Hexanethiol and C₁₂, Dodecanethiol). We also study the thermal desorption of these SAM layers. SAM can minimize the oxidation of the Copper which acts as a bonding medium. By thermal desorption the pure Copper surface is brought back and exposed. Finally Copper-Copper thermocompression bonding is performed in different conditions and compared.

Abstract: In this paper, multiplier decomposition is adopted to examine the effects of expanding grain-based fuel ethanol and cassava-based fuel ethanol on agriculture in China. The results show that, reasonable development of grain-based fuel ethanol has a greater role than cassava-based fuel ethanol in accelerating China’s economy, improve rural household’s income, and mitigate gap between rich and poor

Abstract: In this paper, self-assembled monolayers (SAMs) of stearic acid (SA) surface treatment on pure magnesium were studied to improve bioactivity and corrosion resistance of pure Mg. Three pre-treatment methods (HCl-NaOH treatment, alkali-heat treatment and heat treatment) were used. SAMs treated samples were soaked in simulated body fluid (SBF) and untreated samples were taken as control. The pH variation of SBF solution was examined everyday. The electrochemical property of treated and untreated samples was tested to evaluate the anticorrosion performance of organic surface layer. Scanning electron microscope (SEM), X-ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) analysis were performed to observe the surface appearance and to identify the composition and phases of samples. The results showed that stearic acid SAMs had successfully been assembled on the surface of the samples, which had a good effect on corrosion resistance of materials and decreased the electric current density of SAM-sample 1% to that untreated sample; SAM inhibited the form of Mg(OH)₂ and had a good influence on bioactivities of pure magnesium.