Two-dimensional elemental mapping using glow discharge mass spectrometry
We present a simple modification in the design of glow discharge mass spectrometry (GD-MS) system that allows for two-dimensional (2D) elemental imaging. To obtain 2D images, we used in situ translation of samples with respect to the fixed glow discharge lamp, and thus the image size was not limited by the size of the anode. Using an add-on ‘xyz’ high-vacuum manipulator equipped with a membrane bellow, we obtained 2D images, where pixel-by-pixel acquisition applied for xy maps (7.5 mm × 5.5 mm) consisted of 3040 and 1520 data points. The maps were taken within 25 and 12 min of the total acquisition time, resulting in the spatial resolution in 0.16–0.42 mm range along the x axis. The presented results were obtained using a DC-glow discharge quadrupole mass spectrometer at 1.1 kV DC voltage and 1 mA current. We discuss the applied control procedure of ‘xyz’ manipulator, as well as possible applications of the developed technique for the analysis of homogeneity of materials, distribution of surface impurities, and 3D imaging.