Nitric acid etching

Rupeiez A, Lasema JJ (1994) Surface-enhanced Raman spectrometry on a silver substrate prepared by the nitric acid etching method. Anal Chim Acta 291 147-153... 

To address all these factors, an improved copper cleaning chemistry has been developed by Hoppe, et al. Designed to replace an effective, but overly aggressive concentrated nitric acid etch, this peroxide-based method allows for more controlled cleaning of surfaces. 

Step 5 Nitric acid etching for 10 s at room temperature. 

Solution 1 (100g/l of ZnO) is used (Table 1). Samples are retained at each individual step. Run 1 sample is just after NaOH etch. Run 2 is just after nitric acid etch, but without any zincation. All 3 types of substrates are used. Only CMOS wafer chips are plated with electroless Ni for 1 h after each run. 

Zincation treatment is applied on A1 bond pads in order to activate the A1 surfaces for the adhesion of electroless Ni bumps. Large particles of Zn are deposited on the A1 bond pad surfaces within the first few seconds of zincation. As immersion time proceeds, the size of the particles gets smaller but the coverage of the substrate by Zn particles increases. By SEM/EDX analysis, the dark regions between the deposited particles are shown to remain as untreated Al. Grain boundaries are distinctly observed. Variation of the ZnO content in the zincation baths does not have a visible impact to the deposition during first zincation. Nitric acid etch after the lsl zincation homogenizes the surface before deposition by the 2nd zincation takes place. 

Fig. 4. SEM micrographs after (a) NaOH etch and (b) nitric acid etch for CMOS chip. 

Mercury chloride (ic) Nitric acid etching, aluminum... 

Fig. 6.32 Microstructure of MgO before creep deformation (50 % nitric acid etch X250) [53]. With kind permission of John Wiley and Sons...

Small angle A -ray spectroscopy is also widely" used, and Bassett et al. and others have used nitric-acid etching coupled with gel permeation chromatography to measure the distribution in stem lengths and effect of temperature and pressure on it. Electron microscopy measurements are also popular. ... 

A major problem with nitric acid etching is that it is too strong, etching not only the amorphous surface regions but also the bulk. Chromic acid etching was employed to alleviate this problem. Armond and Atkinson [319] treated PP with fuming nitric acid and then with chromic acid to reveal the cracks and fractures of bulk annealed PP. Bucknall et al. [320] studied... 

The rotor tips are usually clad in electroformed nickel sheet this is chemically pretreated (usually a nitric acid etch [35]), primed and then bonded with a film adhesive curing at 120-130°C. In some cases, due to the increased service temperature requirements caused by underlying heater mats, an adhesive is used, which has enhanced temperature performance. 

Cook JTE, Klein PG, Ward IM, Brain AA, Farrar DF, Rose J. The morphology of nascent and moulded ultra-high molecular weight polyethylene. Insights from solid-state NMR, nitric acid etching, GPC and DSC. Polymer 2000 41 8615. 

Weeks NE, Mori S, Porter RS. The morphology of ultradrawn polyethylene. I. Nitric acid etching plus gel permeation chromatography. J Polym Sci B 1975 13 2031. 

Uehara H, Nakae M, Kanamoto T, Ohtsu O, Sano A, Matsuura K. Structural characterization of ultrahigh-molecular-weight polyethylene reactor powders based on fuming nitric acid etching. Polymer 1998 39 6127. 

Zhang, W., Chen, P., Gao, Q., Zhang, Y. and Tang, Y. (2008) High-concentration preparation of silver nanowires restraining in situ nitric acidic etching by steel-assisted polyol method. Chemical Materials, 20, 1699-704. 

An unusual application of size elution chromatography is the determination of lamellar thicknesses in high pressure crystallized polyethylene [4]. Nitric acid etching was used to remove all but the crystalline molecular stems, which were... 

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