Materials Analytics - Layer and Structure Analysis

The FBH offers its customers comprehensive know-how and a wide range of technical resources in material analytics. The institute provides a broad spectrum of measurement techniques and equipment on the highest technical level. Services in this area of expertise are often demanded to solve complex problems in materials characterization.

In detail, the FBH provides the following analytical methods:

DBR laser structure with AlGaAs self-organization
DBR laser structure with AlGaAs self-organization during overgrowth of grating (BSE image)
X-Ray diffraction Xpert Pro
X-Ray diffraction Xpert Pro
Electroluminescence measurement
Electroluminescence measurement of GaInN-based LED structures
Photoluminescence measurement
Photoluminescence measurement
  • X-ray diffraction
    • High-resolution X-ray diffractometer for precise determination of composition and layer thickness (Philips MRD, PANalytical Xpert Pro)
    • Spatially-resolved X-ray mapping for substrate and layer characterization (Philips DCDM)
  • Atomic force microscopy
    • Mapping of surface roughness (height resolution of about 0.5 nm) (Topometrix Explorer TMX 1010)
  • Luminescence (photoluminescence (PL), electroluminescence (EL)), reflectance, transmittance 
    • RT-PL mapping for determination of emission wavelength and composition homogeneity (Accent PLM 150)
    • Spectral reflectance mapping, transmittance and reflectance measurements for the determination of layer thickness (homogeneity), absorption edges, and DBR mirror characteristics (Accent PLM 150, Filmetrix F20)
    • Low-temperature PL (10 K) for analysis of material quality with excitation by laser wavelengths between 193 nm and 1020 nm
    • Excitation power dependent and temperature dependent PL (10 K - 300 K) for determination of internal quantum efficiency
    • Electroluminescence for determination of spectral emission characteristics and P-U-I curves of LEDs and laser diodes
  • Photocurrent
    • Spectrally- and time-resolved photocurrent measurements for photodiodes
  • Carrier concentration
    • Electro-chemical C-V-measurement of carrier concentration profiles (Accent ECV Pro, Accent PN 4300/4400, Dage UP 21)
    • Sheet resistance mapping (M-RES 2000M)
    • Hall effect measurements for determination of carrier concentration and mobility (temperature dependent, magnetic field dependent)
  • Electron microscopy
    • Scanning electron microscopy for surface analysis and measurement of layer thickness (high-resolution REMs Hitachi S 4800 and Zeiss Ultra+)
    • Cathodoluminescence (77 K) for spatially-resolved measurement of luminescence intensity and wavelength as well as spectrally-resolved mappings and for defect characterization (Zeiss Ultra+)
    • Energy dispersive X-ray spectroscopy EDXS (electron microprobe) for local quantitative determination of compositions und for mappings of element distribution
    • EBIC (electron beam induced current) for determination of p-n-junction position and for localization of defects in semiconductor devices
    • Sample preparation for SEM and TEM (cross section, plan-view preparation)
    • Analytic transmission electron microscopy (TEM at HU Berlin)