Gunther Rodel

Spectrometer system for simultaneous multi-element electrothermal atomic absorption spectrometry using line sources and Zeeman-effect background correction

The design and implementation of a complete instrument system for simultaneous analysis of up to four elements by electrothermal atomic absorption spectrometry is described. The system combines the high throughput per unit spectral bandpass of an echelle optical system with the high quantum efficiency of a custom made solid-state detector. The use of a transversely heated graphite atomizer with integrated platform in a longitudinally oriented magnetic field enables the development of methods for simultaneous multi-element determinations and increases radiation throughput by eliminating the need for a polarizer. Performance characteristics such as optical throughput, spectral resolution and stray light are discussed and correlated with analytical performance using a state of the art single-element atomic absorption spectrometer system as a basis for comparison.

Solid state detector for simultaneous multi-element electrothermal atomic absorption spectrometry with Zeeman-effect background correction

The development and characterization is described of a solid-state detector for simultaneous multielement electrothermal atomic absorption spectrometry (ETAAS) using combined line sources. Photodiode technology providing high quantum efficiency is married to a complementary metal oxide semiconductor (CMOS) charge amplifier array for low noise output. Thus a large surface (3 cm × 6 cm) detector including 60 individual photodiodes can be produced using a high yield-high reliability process to meet the requirements of a simple optical design which has the disadvantage of a large focal plane but the advantages of high throughput and reasonable cost. An evaluation of the opto-electrical characteristics of the detector is described. The significance of the results to applications in ETAAS is discussed.