Three-Dimensional Fusion of Multispectral Secondary Ion Mass Spectrometry Images

Abstract

Imaging secondary ion mass spectrometry (SIMS) is a powerful surface analysis tool capable of producing two-(2D) and three-dimensional (3D) spatially resolved images of element distributions. Both the 2D and the 3D imaging mode produce multispectral images, i.e., each image stack visualises the lateral distribution of one element, which divides the sample information into a number of individual images. Visual perception of the sample information is aggravated by this—for example, the exact spatial location of different elements relative to each other, formation of occlusions or segregations, etc.—is often hard to recognize when looking at n separate images, especially regarding 3D depth profiles. Image fusion is a process whereby images obtained from various sensors, or at different moments of time, or under different conditions, are combined together to provide a more complete picture of the object under investigation. The use of colour introduces a new dimension of information and can be used to simplify image analysis and object identification. This work introduces a complete methodology that enables the calculation and rendering of 3D colour images of multispectral SIMS depth-profiles based on the use of adaptive color and transparency maps. Examples of 3D SIMS images are given but the technique may be expanded to fusion and visualization of any other multispectral 3D image stack.