Oxidative quality

In well-established processes, like ethylene oxidation to ethylene oxide, quality control tests for a routinely manufactured catalyst can be very simple if the test is developed on the basis of detailed kinetic studies and modeling of the performance in a commercial reactor. Tests must answer questions that influence the economics of the commercial process. The three most important questions are ... 

Contamination of silicon wafers by heavy metals is a major cause of low yields in the manufacture of electronic devices. Concentrations in the order of 1011 cm-3 [Ha2] are sufficient to affect the device performance, because impurity atoms constitute recombination centers for minority carriers and thereby reduce their lifetime [Scl7]. In addition, precipitates caused by contaminants may affect gate oxide quality. Note that a contamination of 1011 cnT3 corresponds to a pinhead of iron (1 mm3) dissolved in a swimming pool of silicon (850 m3). Such minute contamination levels are far below the detection limit of the standard analytical techniques used in chemistry. The best way to detect such traces of contaminants is to measure the induced change in electronic properties itself, such as the oxide defect density or the minority carrier lifetime, respectively diffusion length. 

We described (34) use of the test in abused frying oils. We have patented an application to in-package detection of oxidative quality loss. We have studied in this manner the relative effectiveness of antioxidants in a thin layer of dry oil. 

The silicide should give an acceptable oxide quality upon oxidation and should be capable of withstanding high post process temperature steps. 

The planarized structures are at this point ready for follow-on device fabrication processing. Due to the tendency of poor quality oxide in the center region of the filled narrow trenches, a heat annealing of the structure should be made. This improves the oxide quality so that it is nearly equivalent to the regular oxide. Alternatively, a CVDg Q deposition over the back-etched surface... 

Physical hazard of a chemical— A chemical validated as being or having one of the following characteristics combustible liquid, compressed gas, explosive, flannnable, organic peroxide, oxidizing qualities, pyrophoric, unstable, or water reactive. 

Hung, S.S.O. Shnger, S.J. Studies of chemical methods for assessing oxidative quality and storage stabhity of feeding oils. J. Am. Oil Chem. Soc. 1981, 58, 785-788. 

Alloy 5005 contains about 0.6% Mg and replaces 1050A or 1200 whenever a slight improvement in mechanical properties is required. Anodised (OAB quality, anodic oxidation quality for building) or coil-coated 5005 is very widely used for building applications (external cladding panels, etc.). 

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