Elastic Recoil Detection (ERD) is an ion beam analysis technique that measures the composition and depth distribution of light elements in thin films by directing a heavy ion beam (typically 30-200 MeV heavy ions such as Cl, I, or Au, or 2-10 MeV He for hydrogen detection) at a glancing angle to the sample surface and detecting the forward-recoiled target atoms. ERD is complementary to RBS: while RBS excels at detecting heavy elements in light matrices, ERD excels at detecting light elements, particularly hydrogen and its isotopes.

Why ERD Matters in Semiconductor Manufacturing: ERD provides simultaneous, quantitative depth profiling of all light elements (H through F) in a single measurement, filling a critical analytical gap that RBS, SIMS, and XPS cannot address as effectively.

• Hydrogen depth profiling — ERD with MeV He⁺ beams provides absolute hydrogen concentration and depth distribution in a-Si:H, SiNₓ:H passivation layers, and polymer dielectrics without the matrix-dependent sensitivity issues of SIMS • Multi-element light-element profiling — Heavy-ion ERD (HI-ERD) with a ΔE-E telescope detector simultaneously profiles H, D, C, N, O, and F in a single measurement, providing complete light-element depth distributions through thin-film stacks • Absolute quantification — Like RBS, ERD provides standards-free absolute concentration measurements using known scattering cross-sections, making it a primary reference technique for calibrating SIMS and other relative methods • Low-k and organic film analysis — ERD simultaneously measures C, H, O, and N composition profiles in organic low-k dielectrics, photoresist layers, and polymer films, tracking composition changes during processing • Diffusion barrier integrity — ERD detects light-element (C, N, O) redistribution at barrier/Cu interfaces during thermal processing, verifying barrier effectiveness and identifying degradation mechanisms

Elastic recoil detection is the most powerful technique for simultaneous, absolute depth profiling of all light elements in semiconductor thin films, providing standards-free quantification of hydrogen, carbon, nitrogen, oxygen, and fluorine that is essential for characterizing gate dielectrics, barriers, passivation layers, and organic films in advanced device fabrication.