Papers by Keyword: Hydrogen Peroxide

Abstract: Metallic contamination is a major challenge in multiple semiconductor processes, including photolithography and wet etch and cleans (WEC). Though there are several contributors to metallic contamination, significant efforts have focused on improving the incoming quality of process chemicals, especially commodity chemicals. Another key contributor to on-wafer metallic contamination is water (H2O), which is used to dilute most aqueous chemicals. Single Particle Inductively Coupled Plasma Mass Spectroscopy (SP-ICP-MS), a technique relying on time-based resolution of pulses generated during a standard ICP-MS analysis, is used to aid the understanding of metal particle contamination in water and process chemicals.In this paper, we studied water and 30% Hydrogen Peroxide (H2O2), two of the most widely used chemicals across all WEC processes. We used a high purity grade of 30% H2O2, further diluted to a typical use concentration (5% by volume) using two grades of Deionized Water (unfiltered and filtered) where the concentration of metallic particles was the key variable. The metals studied included Iron (Fe), Chromium (Cr), Zinc (Zn), Titanium (Ti), Nickel (Ni) and Aluminum (Al), representing some of the most commonly observed metallic contaminants in H2O2 and water. After analyzing the distribution of contaminants in the chemicals, filters were introduced into the system to observe the impact of filtration on metal removal. The importance of filtration on the overall quality of the diluted process chemical was demonstrated by using a Polysulfone (PS) membrane to filter the lower grade Deionized Water (DIW).

Abstract: Hydrogen peroxide is a strong oxidizing agent containing a peroxide functional group that easily decomposes. In this research, a commercial grade of 35 % w/w hydrogen peroxide was evaluated for thermal hazard and reactivity by differential scanning calorimetry (DSC). It was found that the calculated activation energy was 70.03 kJ/mol. The risk assessment of thermal hazard evaluated in terms of the adiabatic decomposition temperature rise at heating rate 2, 4 and 8 °C/min, were 236.5, 159.2 and 217.5 K, respectively. While the time-to-maximum rate were 79.1, 52.6 and 28.3 second, respectively. Therefore, the storage, transportation and usage, proper care must be highly careful by trained and qualified person or the chemist knowledgeable personnel.

Abstract: The problem of copper leaching from copper-electrolyte slimes is discussed. To intensify the long and costly process, it is proposed to use a leaching system containing sulfuric acid and hydrogen peroxide as an oxidizing agent. The chemical transformations possible variants at the treatment of slime under the specified conditions and the thermodynamic parameters of the predicted reactions are considered. Solution composition effect on the copper dissolution rate at room temperature was studied in the presence of hydrogen peroxide using the rotating disc technique. It is found that dissolution rate constant at using hydrogen peroxide slightly inferior to dissolution rate constant under autoclaved conditions in an oxygen atmosphere.

Abstract: The work is devoted to the study of the possibilities of minimizing the release of nitrogen oxides during the dissolution of silver in nitric acid solutions during refining of the gold and silver alloy. Using a rotating disk, the maximum concentration of nitric acid is determined, at which the oxidation potential of the system is insufficient for the oxidation of silver. It has been established that at a temperature of 363 K and a concentration of HNO₃ = 50 g/l, the dissolution rate of silver does not exceed 0.00022∙10^-5 mol/(cm²∙s), and such conditions can be considered as background for an environmentally friendly process. To initiate dissolution, hydrogen peroxide was used as an alternative oxidizing agent. As a criterion for the rational use of the oxidant and the ecological purity of the process, the excess pressure over the solution was evaluated. The influence of the initial and current composition of the solution, temperature, and conditions of oxidant supply to the reactor on the kinetics of the target process was studied. It is shown that at a silver dissolution rate of 2.7∙10^-6 mol/(cm²∙s), no release of nitrogen oxides was observed.

Abstract: In this paper we demonstrate an effective process control mechanism to significantly improve on the process performance of a BEOL post-etch cleaning process with an integrated partial or complete removal of the TiN HM (hard mask) layer by so called formulated chemistries on a single wafer processing tool. The novel process control mechanism enables a 50% reduction in chemical consumption while achieving an at least equivalent TiN etch uniformity.

Abstract: The introduction of Co into MOL and BEOL requires a robust wet clean, especially the optimization of the Co rinsing step seems to be critical. The wafer rinsing solutions with a precisely controlled pH and oxidizing additive have been developed to suppress the Co corrosion. In addition, the mechanism of passivation and corrosion of the cobalt surface as well as the passivation stability is discussed.

Abstract: Synthetic hydroxyapatite (HAp) has weak antibacterial and mechanical properties. The antibacterial activity of HAp can be enhanced by strontium cation substitution and incorporation of peroxide ion via hydrothermal processing at 100 °C and 150 °C temperature using 50% H₂O₂ solution. The starting reagents and products of HAp processing were analyzed by thermal conversion elemental analyser – isotopic ratio mass spectrometer in order to determine the δ¹⁸O values. Using different host materials it could be possible to determine differences of δ¹⁸O values between untreated and hydrothermally treated HAp samples. The enhanced antibacterial properties of processed HAp samples were investigated using Pseudomonas aeruginosa and Staphylococcus aureus. Hydrothermal processing by H₂O₂ solutions provides additional antibacterial activity and peroxide content of hydrothermally treated samples affect δ¹⁸O values.

Abstract: It was established that the silver nanoparticles (AgNPs) in an equimolar ratio have the highest electrochemical activity on a graphite electrode (GE) surface in an alkaline medium. The electrocatalytic oxidation mechanism of hydrogen peroxide on the GE surface was proposed. We detected an additional maximum at E = 0.3 V on the cathodic branch of the cyclic curve in the potential range from +2.0 to -1.0 V. The appearance of this maximum indicates the reduction of hydrogen peroxide generated during AgNPs electrooxidation in the potential range from -1.0 to +2.0 V.

Abstract: This paper describes a pneumatically powered system based on hydrogen peroxide (H₂O₂) decomposition designed to provide enhanced energy and power density for wearable robotic applications. As one of the energy material, hydrogen peroxide shows good potentials for some applications like jet packs. In particular, the authors establish the pressurization system based on high frequency switch valves which involves a periodic pulsed gas explosion as a result of inspiration from the bombardier beetle. Then numerical simulations of spray force produced by the H₂O₂ based power system are presented. And the power system is used in movement enhanced jet pack in the end. The results show that spray force of the pulsed power system is directly proportional to the flow rate of H₂O₂, while inversely proportional to the volume of catalyst pack. At last the relationship between power system parameters and spray performances are discussed in detail.

Abstract: Hydrogen peroxide (H₂O₂) is a stronger oxidizing agent relative to the commonly used H₂O in anodization of Titania Nanotube (TNT). Despite having higher oxide growth rate and more superior photocatalytic property, the substitution of H₂O₂ as oxygen source is sometimes accompanied with foil corrosion. In this work, it is shown that foil corrosion is originated from temperature elevation during anodization process. Conversely, foil corrosion can be prevented by monitoring the anodization temperature. Essentially, the corrosion of foil is not directly influenced by the type of oxidation source used. Foil corrosion occurs due to temperature elevation when using H₂O₂ as oxidation source.