Elemental Analysis is a process where a sample of some material (e.g., soil, waste, minerals, chemical compounds) is analyzed for its elemental and sometimes isotopic composition. Elemental analysis can be qualitative (determining what elements are present), and it can be quantitative (determining how much of each are present). Elemental analysis falls within the ambit of analytical chemistry, the set of instruments involved in deciphering the chemical nature of our world.
Quantitative analysis is the determination of the atom% or weight% of each element present. Other quantitative methods include:
To qualitatively determine which elements exist in a sample, the methods are:
Elemental composition analysis is generally the confirmation of the identity and amounts of the major elements present in a material or film.
The technique of choice for the analysis depends on:
- What is known about the sample?
- What needs to be quantified (major elements, minor elements, chemical compounds, or molecular components)?
- Is this a surface, bulk or layer analysis?
Surface Chemical Analysis
Elemental and chemical state compositions are best measured using quantitative techniques with shallow depths of information (<120Å), such as X-Ray Photoelectron Spectroscopy.
Bulk composition is best determined with techniques that have large/deep depths of information that don’t measure the variations at surfaces. X-ray Fluorescence (XRF) and Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) are the most common techniques that can quantify both major and minor elemental components.
Thin Layer Analysis
- X-ray Photoelectron Spectroscopy (XPS) is an excellent choice for both thin layers and bulk analysis.
- Fourier Transform Infrared Spectroscopy (FTIR) and Raman Spectroscopy are well suited for molecular information from organic films.
- Raman Spectroscopy is well suited for molecular information from inorganic compounds, but not pure metals.
- Secondary Ion Mass Spectrometry (SIMS) has a range of applications for high precision measurement of compound semiconductor thin films.