Depth Profiling of Thin Films Using the fibTOF for FIB-SIMS Measurements

Thin films with desired mechanical, electrical, and optical properties are ubiquitous in modern life, with applications ranging from simple protection or antireflection coatings to hard layers for tools and complex multilayer structures on semiconductor wafers. Thin films on complex substrates are also increasingly important in clean energy storage applications such as lithium-ion batteries. The deposition of such advanced thin films, especially on small parts with complex shapes, is a challenging process requiring complex development and verification activities. The use of a fibTOF secondary ion mass spectrometer can accelerate this development by providing information about the elemental composition of the layer structure. This information concerns the chemical homogeneity both at the surface and in buried layers (such as an adhesion layer), the detection of contaminants (often present at the interface between two layers) and the sharpness of interfaces between layers. Although secondary ion mass spectrometry has long been used to analyze thin films [1], the fibTOF advances the method by providing high resolution chemical images and does not require choosing the elements of interest before analysis. In this application note, we present two examples of inorganic thin film measurements using a fibTOF.