Removal of residual CuO particles on the post CMP wafer surface of multi-layered copper

This article introduces the removal technology of CuO particles on the post CMP wafer surface of multi-layered copper. According to the Cu film corrosion curve with different concentrations of HEO2 and the effect curve of time on the growth rate of CuO film, CuO film with the thickness of 220 nm grown on Cu a surface was successfully prepared without the interference of CuC12.2H20. Using the static corrosion experiment the type of chelating agent （FA/O II type chelating agent） and the concentration range （10-100 ppm） for CuO removal was determined, and the Cu removal rate was close to zero. The effect of surfactant on the cleaning solution properties was studied, and results indicated that the surfactant has the effect of reducing the surface tension and viscosity of the cleaning solution, and making the cleaning agent more stable. The influence of different concentrations of FA/O I type surfactant and the mixing of FA/O II type chelating agent and FA/O I type surfactant on the CuO removal effect and the film surface state was analyzed. The experimental results indicated that when the concentration of FA/O I type surfactant was 50 ppm, CuO particles were quickly removed, and the surface state was obviously improved. The best removal effect of CuO on the copper wiring film surface was achieved with the cleaning agent ratio of FA/O II type chelating agent 75 ppm and FA/O I type surfactant 50 ppm. Finally, the organic residue on the copper pattern film after cleaning with that cleaning agent was detected, and the results showed that the cleaning used agent did not generate organic residues on the film surface, and effectively removes the organic residue on the water.

Effect of CeO_(2)on Activity of Catalysts CuO/ZnO/Al_(2)O_(3)/CeO_(2)for Synthesis of Methanol

The size of the nanoparticles and the number of oxygen vacancies have a significant effect on the catalytic activity of copper-based catalysts used for the synthesis of methanol from syngas.In this study,the authors prepared a series of catalysts CuO/ZnO/Al_(2)O_(3)/CeO_(2)(CZAC)with CuO particles of different sizes and varying number of oxygen vacancies on the surface by changing the added volume of CeO2 by using the co-precipitation method.The properties of the catalysts were characterized and their activity was evaluated by using high-pressure fixed-bed reaction equipment.The results showed that the addition of CeO_(2)to CuO/ZnO/Al_(2)O_(3)not only influenced the size of the CuO particles and metal-metal interactions,but also had an effect on the concentrations of oxygen vacancies and strongly basic sites.The presence of CuO particles of small sizes and a large numbers of oxygen vacancies on the surface of the catalyst were beneficial to its activity for the synthesis of methanol.The catalyst CZAC,when modified by 5%of CeO_(2),recorded CuO particles of the smallest size(8.9 nm),strong intermetallic interactions,and the highest concentrations of oxygen vacancies and strongly basic sites.It also exhibited the highest catalytic activity,with a space-time yield of methanol of 0.315 g/(h·g)that was higher than that of the enterprise RK-5 catalyst[0.215 g/(h·g)].

Effective photodegradation of 4-nitrophenol with CuO nano particles prepared by ionic liquids/water system

The hydrophobic ionic liquids/water two-phase system was developed to prepare CuO nano particles.The catalytic activity of the synthesized CuO was investigated by photodegradation of 4-nitrophenol(4-NP)in the presence of H_(2)O_(2) under visible light irradiation.The optical properties of the synthesized CuO were characterized by ultraviolet–visible(UV–Vis)diffuse reflectance spectroscopy(DRS).Experimental results indicated that the band gap energy(Eg),conduction band edge potential(ECB)and valence band edge potential(EVB)of the synthesized CuO were 1.37 e V,0.625 e V and 1.995 e V,respectively.A degradation efficiency of 4-NP(4.8 mmol L^(-1))as high as 95.3% could be achieved under the conditions of p H 6.0,0.48 g L^(-1)of CuO dosage,1.4% of H_(2)O_(2) dosage and 90 min of degradation time.The synthesized CuO exhibited poor catalytic activity under alkaline conditions due to the disassociation of 4-NP,which elevated the repulsion between CuO and the 4-NP anions.The synthesized CuO nano particles exhibited higher catalytic activity compared with the catalysts reported in literature.Furthermore,the synthesized CuO nano particles could be reused at least six times without decreasing their catalytic activity.Compared with the traditional hydrothermal method,mild operating conditions and time saving are the advantages of the developed method for the preparation of CuO.

Effect of CuO Particle Size on the Microstructure Evolution of Al_2O_(3P)/Al Composites Prepared Via Displacement Reactions in the Al/CuO System

An A1203p/A1 composite was successfully synthesized using a displacement reaction between 80 wt% A1 and 20 wt% CuO powders at a heating rate of 5 ℃/min. Two different sizes CuO particles were used, and all the experiments were conducted under an argon atmosphere. To analyze the microstructural evolution during synthesis, the A1-20 wt% CuO samples were heated to the temperatures selected according to the differential scanning calorimetry curve and then immediately quenched with water. The phase composites and microstructure of the water-quenching samples were in- vestigated using X-ray diffraction, optical microscopy, scanning electron microscopy and energy-dispersive spectrometry. The results indicate that the CuO particle size has a significant effect on the microstructural evolution of the samples during the heating stage and on the microstructure of synthesized composites. Smaller CuO particles can decrease the reaction temperature, narrow the reaction temperature range at the different reaction stages during the heating stage and make the size and distribution of in situ A1203 particles more uniform. The reaction between A1 and CuO can be complete as the temperature rises to 900 ℃. The size of the in situ A1203 particles is approximately 5 μm when the size of the CuO particles is less than 6 μm. This sample has a relatively high Rockwell hardness of 60 HRB.

Effect of Cu-ZSM-5 catalysts with different CuO particle size on selective catalytic oxidation of N,N-Dimethylformamide

N,N-Dimethylformamide(DMF),a nitrogen-containing volatile organic compound(NVOC)with high emissions from the spray industry,has attracted increasing attention.In this study,Cu-ZSM-5 catalysts with different CuO particle sizes of 3,6,9 and 12 nm were synthesized and tested for DMF selective catalytic oxidation.The crystal structure and physicochemical properties of the catalyst were studied by various characterization methods.The catalytic activity increases with increasing CuO particle size,and complete conversion can be achieved at 300-350℃.The Cu-12 nm catalyst has the highest catalytic activity and can achieve complete conversion at 300℃.The Cu-6 nm sample has the highest N_(2)selectivity at lower temperatures,reaching 95%at 300℃.The activity of the catalysts is determined by the surface CuO cluster species,the bulk CuO species and the chemisorbed surface oxygen species.The high N_(2)selectivity of the catalyst is attributed to the ratio of isolated Cu2+and bulk CuO species,and weak acidity is beneficial to the formation of N_(2).The results in this work will provide a new design of NVOC catalytic oxidation catalysts.