resonant soft x-ray scatterometry

**Resonant Soft X-ray Scatterometry** is an **advanced X-ray metrology technique that tunes the X-ray energy to elemental absorption edges** — providing material-specific contrast in addition to geometric information, enabling simultaneous measurement of structure AND composition in nanoscale features. **Resonant Soft X-ray Approach** - **Tunable Energy**: Use synchrotron or advanced lab sources to tune X-ray energy to specific absorption edges (C, N, O, Si K-edges at 100-500 eV). - **Material Contrast**: At resonance, the scattering contrast between materials is dramatically enhanced — distinguish materials with similar electron density. - **RSOXS**: Resonant Soft X-ray Scattering — combines SAXS with resonant energy tuning. - **Multi-Energy**: Measure at multiple energies around absorption edges for maximum material discrimination. **Why It Matters** - **Composition + Geometry**: Standard scatterometry measures shape; resonant adds material composition — more information per measurement. - **Block Copolymers**: Essential for characterizing directed self-assembly (DSA) — distinguish polymer blocks with similar density. - **Chemical Profiles**: Measure compositional gradients at interfaces — diffusion profiles, intermixing. **Resonant Soft X-ray Scatterometry** is **element-specific nano-vision** — combining structural measurement with material identification through resonant X-ray contrast.