Spark source mass spectrography

Analyses done by spark source mass spectrography. 

Trace Element Survey Analyses by Spark Source Mass Spectrography... 

The role of Spark Source Mass Spectrography (SSMS) as a high sensitivity trace element analytical method is discussed. The unparalleled combination of sensitivity and complete element coverage makes SSMS especially suitable for the analysis of liquid and solid materials involved in semiconductor processing. Sample requirements are discussed. The application of SSMS to semiconductor materials, process reagents, dopants, and metals, is Illustrated. Advantages and disadvantages of the technique as well as sensitivity and accuracy are discussed. 

Exactly twenty-three years ago this week a conference was held in Boston on ultrapurification of semiconductor materials. One third of the papers at that conference were devoted to Impurity analyses G). Spark source mass spectrography was the newest and most promising analytical technique available at the time, and I would like to compare the status of SSMS at that time to Its present status. 

Spark source mass spectrography is the most useful tool available to the microelectronics industiry for bulk trace level impurity analyses of a wide variety of materials. The technique routinely examines ciTTstal growth start materials, crucibles, finished crystals, dopants, solvents, metals and all substances used in microelectronics manufacture. 

Taylor S.R. and Gorton M.P., 1977, Geochemical applications of spark-source mass spectrography, III. Element sensitivity, precision and accuracy. Ceochim. Cosmochim. Acta, 41, 1375-1380. 

Taylor, S.R., 1965a, Geochemical application of spark source mass spectrography. Nature 205, 34. 

Emission spectrography permits the determination of germanium at 1 xg, spark source mass spectrometry at 7 fJLg/kg wet weight. Neutron activation analysis with 7-spectrometry detects about 30 p-g/kg dependent on the matrix when p-rays from interfering substances are magnetically deflected [46]. 

There are many analytical techniques which may be used for lead analysis. These include X-ray fluorescence (XRF) spectroscopy, radioactivation methods, emission spectrography, ring oven methods, polarographic techniques [including anodic stripping voltammetry (ASV)], spark source mass spectrometry, colorimetry and atomic absorption spectrometry (AAS). Background information upon all of these methods may be found in the Handbook of Air Pollution Analysis [1]. 

For ion detection, several approaches are possible. Classical spark source mass spectrometry has developed the use of photographic plates. Very hard emulsions with low gelatin content are required. Emulsion calibration is similar to that described in optical emission spectrography, but usually varying exposure time are applied instead of using optical step filters. Provided an automated microdensitometer is used, mass spectrography is still a useful tool for survey analysis of solids down to the sub-pg/g level. 

In classical spectrographic analysis (i.e., direct current arc and controlled-waveform spark emission spectrography) the easiest method for sample introduction involved the direct analysis of solid samples.This approach was also used as the conventional sampHng technique for trace element analysis by spark-source mass spectrometry. Solid samples were easy to prepare, usu-... 

Nicholls, G.D., A.L. Graham, E. Williams and M. Wood, 1967, Precision and accuracy in trace element analysis of geological materials using solid source spark mass spectrography. Anal. Chem. 39, 584. 

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