Simulation and iterative deconvolution of residual gas spectra

Abstract

Residual gas analysis may be time consuming if the identification of all gas species and their quantitative contribution to the mass spectrum is required. This is because the partial pressures of the residual gas cover several orders of magnitudes and fragmentation patterns are in general convoluted. Noise, offset, and the limited mass ranges of the analysers used in UHV applications further reduce the sensitivity of a spectrum. In this work, the authors propose a method to simulate residual gas spectra based on fragmentation patterns and partial pressures. With an iterative algorithm, residual gas spectra can be deconvoluted in logarithmic scale. The use of indicators simplifies the identification of residual gas compositions. The authors realised this algorithm in a prototype application. The performance of this tool is encouraging and opens the path for the development of an UHV specific web-based application.