1. Theoretical Aspects2. Instrumentation3. Using Optical Parameters to Determine Material Properties4. Determining Optical Parameters for Inaccessible Substrates and Unknown Films5. Extremely Thin Films6. The Special Case of Polysilicon7. The Effect of RoughnessCase StudiesCase 1. Dissolution and Swelling of Thin Polymer FilmsCase 2. Ion Beam Interaction with SiliconCase 3. Dry Oxidation of MetalsCase 4. Optical Properties of Sputtered Chromium Suboxide Thin FilmsCase 5. Ion-assisted Film Growth of Zirconium DioxideCase 6. Electrochemical/Ellipsometric Studies of Oxides on MetalsCase 7. Amorphous Hydrogenated Carbon FilmsCase 8. Fluoropolymer Films on Silicon from Reactive Ion EtchingCase 9. Various Films on InPCase 10. Benzotriazole and Benzimidazole on CopperCase 11. Gas Adsorption on Metal SurfacesCase 12. Silicon-Germanium Thin FilmsCase 13. Profiling of HgCdTeCase 14. Oxides and Nitrides of SiliconAppendices