Microstructure Analysis

Fraunhofer-Center Nanoelektronische Technologien

Microstructural

Spectroscopic Ellipsometry (SE)

SE
3D Wafermap of a BOW measurement
Applications
 
• Film thickness
• BOW measurement
• Roughness
• N&k measurement
• Material compounding
• 200mm and 300mm wafer compatible

Scatterometry:
• 2D- and 3D Scatterometry possible
• Optical CD
• Wall angle
• Profile
• Bow and Dishing of Profile

Technical Specifications
 
• Elliptic polarized light (xenon lamp)
» Wavelength: 250 – 800nm
• Detection of n&k and phase shift
• Model matching 
• Different dispersion models:
» Table (tabular listing)
» Cauchy cubic polynomials
» Harmonic oscillator
» Bruggeman effective medium approximation (BEMA)
» Lookup table
» And still more models
• Different objective (1x, 2x (SWE), 4x, 15x)
• iDesorber (10 – 40mW)
• High Mag refinement (optic)
• Site by site positioning possible (alignment at every measurement point)
• Different brightness and color filters
• Automated pattern recognition
• Different rotation of the Wafer is possible (to measure diagonal structures)
• Wafer map creator inside the software
 
Research Areas
 
• Fast and effective measurement for different applications
• Process monitoring (blanked and structured)
• Tool monitoring (deposition- and etching Tools)
• New material research
 

Different measurement functions

SE (spectroscopic ellipsometry) For most applications
DBS (dual beam spectrometry) For thicker material
SWE (single wavelength ellipsometry) To measure thin oxide (<10nm)
BOW Stress measurement
Scatterometry Model library based measurement for different structures
CDX Non library based measurement for simple structures (Model is also used)
iDesorber burn the surface oxide to measure more stable