Evaluation of a 512-Channel Faraday-Strip Array Detector Coupled to an Inductively Coupled Plasma Mattauch−Herzog Mass Spectrograph

• Published in: Analytical chemistry (Washington) 2009-07, Vol.81 (13), p.5467-5473
• Main Authors: Schilling, Gregory D, Ray, Steven J, Rubinshtein, Arnon A, Felton, Jeremy A, Sperline, Roger P, Denton, M. Bonner, Barinaga, Charles J, Koppenaal, David W, Hieftje, Gary M
• Format: Article
• Language: English
• Subjects: Analytical chemistry; Chemistry; Correlation analysis; Exact sciences and technology; Plasma; Semiconductors; Spectrometric and optical methods
• ISSN: 0003-2700; 1520-6882
• DOI: 10.1021/ac900640m

A 512-channel Faraday-strip array detector has been developed and fitted to a Mattauch−Herzog geometry mass spectrograph for the simultaneous acquisition of multiple mass-to-charge values. Several advantages are realized by using simultaneous detection methods, including higher duty cycles, removal of correlated noise, and multianalyte transient analyses independent of spectral skew. The new 512-channel version offers narrower, more closely spaced pixels, providing improved spectral peak sampling and resolution. In addition, the electronics in the amplification stage of the new detector array incorporate a sample-and-hold feature that enables truly simultaneous interrogation of all 512 channels. While sensitivity and linear dynamic range remain impressive for this Faraday-based detector system, limits of detection and isotope ratio data have suffered slightly from leaky p−n junctions produced during the manufacture of the semiconductor-based amplification and readout stages. This paper describes the new 512-channel detector array, the current dominant noise sources, and the figures of merit for the device as pertaining to inductively coupled plasma ionization.