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1.
M. Stangl V. Dittel J. Acker V. Hoffmann W. Gruner S. Strehle K. Wetzig 《Applied Surface Science》2005,252(1):158-161
At room temperature electroplated copper layers exhibit changes in resistivity, residual stress, and microstructure. This process, known as self-annealing, is intimately linked to the release of organic impurities, which stem from the incorporation of organic additives into the Cu layer in the course of the electroplating process. The behavior of these impurities during self-annealing, represented by the carbon content, could be detected by analytical radio frequency glow discharge optical emission spectrometry (GD-OES) and carrier gas hot extraction (CGHE). The precondition of a quantitative determination is a surface cleaning procedure to remove adsorbed organics from the copper surface. It was observed that at first almost all impurities have to leave the Cu metallization before an accelerated abnormal grain growth can start. The small amount of remaining organic species after self-annealing could be quantified by both examination techniques, GD-OES and CGHE. 相似文献
2.
Dorris Heiligmann und L. Acker 《Fresenius' Journal of Analytical Chemistry》1955,144(4):291-294
Ohne Zusammenfassung 相似文献
3.
The chemical etching of silicon using HF-HNO3 mixtures is a widely used process in the processing of silicon wafers for microelectronic or photovoltaic applications. The control of the etch bath composition is the necessary condition for an effective bath utilization, for the replenishment of the consumed acids, and to maintain a certain etch rate. The present paper describes two methods for the total analysis of the individual etch bath constituents HF, HNO3, and H2SiF6. Both methods start with an aqueous acid-base titration determining the total acid concentration and the concentration of H2SiF6. The first method is an acid-base titration using a 0.1 mol L−1 methanolic solution of cyclohexylamine (CHA) as non-aqueous titrant to determine the content of nitric acid. Then, the amount of hydrofluoric acid is calculated from the difference between the total acid and nitric acid content. The second method is based on the determination of the total fluoride concentration using a fluoride ion-selective electrode (F-ISE). The content of hydrofluoric acid is obtained from the difference between the total fluoride content and the amount of fluoride bound as H2SiF6. The amount of nitric acid results finally calculated as difference to the total acid content. 相似文献
4.
L. Acker 《Fresenius' Journal of Analytical Chemistry》1960,173(2):168
Ohne Zusammenfassung 相似文献
5.
L. Acker 《Fresenius' Journal of Analytical Chemistry》1960,178(3):228
Ohne Zusammenfassung 相似文献
6.
L. Acker 《Fresenius' Journal of Analytical Chemistry》1960,178(1):80
Ohne Zusammenfassung 相似文献
7.
L. Acker 《Fresenius' Journal of Analytical Chemistry》1960,176(2):143
Ohne Zusammenfassung 相似文献
8.
A. G. Gagliano † N. E. Geacintov ‡ J. Breton S. Acker R. Remy § 《Photochemistry and photobiology》1979,29(2):415-418
Abstract— The P700 chlorophyll a -protein complex (CPI) isolated from green plants was oriented in aqueous solutions using pulsed electric fields of up to 6700 V cm-1 . The electric linear dichroism spectrum is reported in the range of 400–720nm. Positive peaks in the linear dichroism Δ A = A I - A 1 (where AI and A1 are the absorbance components in which the polarizer orientation is parallel and perpendicular with respect to the electric field. respectively) are observed at 443 and 686 nm. The ΔA signal at 686 nm is discussed in terms of either a specialized chlorophyll form absorbing at 686 nm. or due to an exciton component absorbing at the same wavelength. 相似文献
9.
In the photovoltaic industry the etching of silicon in HF/HNO3 solutions is a decisive process for cleaning wafer surfaces or to produce certain surface morphologies like polishing or texturization. With regard to cost efficiency, a maximal utilisation of etch baths in combination with highest quality and accuracy is strived. To provide an etch bath control realised by a replenishment with concentrated acids the main constituents of these HF/HNO3 etch solutions including the reaction product H2SiF6 have to be analysed. Two new methods for the determination of the total fluoride content in an acidic etch solution based on the precipitation titration with La(NO3)3 are presented within this paper. The first method bases on the proper choice of the reaction conditions, since free fluoride ions have to be liberated from HF and H2SiF6 at the same time to be detected by a fluoride ion-selective electrode (F-ISE). Therefore, the sample is adjusted to a pH of 8 for total cleavage of the SiF62− anion and titrated in absence of buffers. In a second method, the titration with La(NO3)3 is followed by a change of the pH-value using a HF resistant glass-electrode. Both methods provide consistent values, whereas the analysis is fast and accurate, and thus, applicable for industrial process control. 相似文献
10.
L. Acker 《Fresenius' Journal of Analytical Chemistry》1960,174(1):77
Ohne Zusammenfassung 相似文献