X-ray Reflectivity
Specular X-ray Reflectivity (XRR), a technique related to X-ray Diffraction (XRD), is becoming a widely used tool for the characterization of thin-film and multilayer structures. X-ray scattering at very small diffraction angles allows characterization of the electron density profiles of thin films down to a few tens of Ǻ. Using a simulation of the reflectivity pattern, a 
highly accurate 
measurement of thickness, interface roughness, and layer density for either crystalline or amorphous thin films and multilayers can be obtained. No prior knowledge or assumptions regarding the optical properties of the films are required, unlike optical ellipsometry
Main Applications
- Determination of thickness, interface roughness, and density for thin films and multi-layers
- Highly accurate film thickness and density measurement
- Measuring film or interface roughness
- Measuring film uniformity across wafers
- Measuring pore density and pore size of low-k films
Signal Detected: Reflected X-rays
Elements Detected: No elements are specifically detected, rather the electron density of the layers is measured. This, combined with knowledge of the layer composition, allows an exact determination of layer thickness and density.
Detection Limits: 30-100Ǻ minimum layer thickness
Depth Resolution: ~1% of measured thickness
Imaging/Mapping: Yes
Lateral Resolution/Probe Size: ~1cm
- Whole wafer analysis (up to 300mm) as well as irregular and large samples
- Mapping of full wafers
- Conductor and insulator analysis
- Optical properties of the film are not required for accurate thickness determination
- Minimal or no sample preparation requirements
- Ambient conditions for all analysis
- Some knowledge of the expected basic sample structure (the order of layers and their approximate compositions) is needed in order to provide accurate density results
- Maximum film thickness ~300nm
- Compound Semiconductor
- Data Storage
- Defense
- Displays
- Electronics
- Photonics
- Semiconductor
- Solar Photovoltaics
- Telecommunication
Related Application Notes
Related Brochures
- EAGLABS Bubble Chart: Analytical Resolution versus Detection Limit BR004
- Materials Characterization Brochure
- PV Materials Characterization for CIGS BR053
- PV Silicon Impurity Analysis BR025
- PV Materials Characterization for CdTe BR054
- Typical Applications for Techniques / Periodic Table of Elements BR038
- Your Solution for PV Materials Characterization BR032
- Compound Semiconductors for Optoelectronics - SIMS Analytical Services BR010
- Contamination Analysis for Compound Semiconductors - Analytical Services BR006
- EAG Services Introduction BR011
