Physical Metrology

The department has extensive expertise in the physical characterization of materials, surfaces, and functional materials. This includes optical, thermal, structural, and surface analytical methods, as well as methods for determining material properties under varying environmental and excitation conditions.

Another focus is the quantitative characterization of optical properties such as emission, transmission, reflection, and scattering behavior, as well as the analysis of thermal material properties and transitions. In addition, structural properties such as crystallinity, crystal orientation, and strain, as well as surface-related parameters, are investigated with high spatial resolution.

The range of expertise also includes the characterization of phosphors and light-emitting systems with regard to spectral properties, efficiency, angular dependence, and stability under thermal and optical stress. The investigation of surface and interface properties, as well as the analysis of material behavior under temperature and environmental stress, complement the department's range of services.

Environmental risk assessment of substances

• Physically measurable substance properties with potential hazards
• Physical measurement methods for chemicals and particles
• Physically measurable environmental conditions relevant to organisms
• Physically measurable responses of organisms to stress

Characterization and evaluation

• Determination of absolute photoluminescence quantum efficiency
• Measurement of photoluminescence excitation and emission spectra, (temperature and/or angular resolved)
• Reflection, transmission and scattering measurements (UV-Vis-NIR)
• Measurement of the bidirectional scattering distribution function (BRDF, BTDF)
• X-ray diffraction: crystal structure, crystallinity, crystal orientation and strain
• Calorimetric methods for determination of specific heat capacity as well as transition, crystallization and melting temperatures
• Measurement of luminous intensity distribution in far field
• Determination of color distribution by measurement of angular resolved emission spectra
• Measurement of luminance and luminance distribution (near field) at different angles
• Thermal analysis of a wide range of high-performance materials such as high-temperature polymers, ceramics, glasses, composites, metals, or crystals
• Evaluation of phosphor stability at elevated ambient temperatures and high excitation powers

Fabrication and development

• Fabrication and development of different glass systems
• Investigations of glass ceramics
• Vacuum deposition under high-vacuum conditions for small-scale production, primarily using gold, silver, and aluminum

Thermal management

• Analysis of heat development and heat propagation by imaging infrared thermography
• Determination of thermal parameters such as thermal diffusivity, thermal conductivity, specific heat capacity
• Measurement of temperature differences and visualization of heat sources with active (lock-in) thermography

Surface and elemental analyses

• Thermal and thermokinetic analyses
• 3D laser scanning microscopy for contact-free and non-destructive topographic analysis
• Electron microscopy
• Measurement of the angular dependent reflectance and transmittance of surfaces, coatings, and materials

• 3D laser scanning microscope
• electron microscope with energy-dispersive x-ray detector (EDX)
• glove box with inert atmosphere and high-frequency induction furnace
• high temperature furnace up to 1700 °C
• photoluminescence quantum yield measurement setup
• six-axis robot goniophotometer
• infrared thermography system (active/passive)
• CO2 laser for scribing
• ultrashort pulse laser system
• photoluminescence setup with cryostat system and high temperature unit (from 10 K up to 700 K)
• differential scanning calorimetry up to 1500 °C
• precision scale with density measurement unit
• FT-IR spectrometer with emission unit
• Raman spectrometer
• US-Vis-NIR spectrometer with integrating sphere
• light scattering measurement system
  
• X-ray diffractometer for stress, texture, and phase analysis with high temperature unit and thin film setup, sample changer
• setup for long-term stability investigations in the temperature range from 4 °C to 220 °C