Wafer Level Packaging

Layer Analysis

EDS and Micro-XRF

EDS and Micro-XRF can not only determine the composition of thin metallic films, it can also be used to calculate the coating thickness of such layers. Different models are employed for electron excitation (StrataGEM) and photon excitation (XMethod). Micro-XRF can even be used without standards, utilizing a fundamental parameter based approach to calculate the thickness from multilayer stacks.

Passivation Layer and Layer Thickness Analysis by FT-IR

Passivation layers on semiconductors play an important role and serve as e.g. protection, electronic isolation or antireflectance layer. Bruker FT-IR research spectrometers are the ideal tools for the fast, sensitive and non-destructive analysis of such passivation layers.

  • Quantification of Boron and Phosphorous Phosphosilicate glass (PSG) and Borophosphosilicate glass (BPSG)
  • Analysis of SiN plasma layers and Silicon Oxide based passivation layers
  • Investigation of ultra-low k layers

FT-IR spectrometers allow determining the layer thickness of semiconductor layer structures with highest accuracy. This application is based on the evaluation of interferences created by the investigated layers and can be applied to layers with a thickness between less than 1 micron and up to several mm.

Doping Concentration and Wafer Mapping by FT-IR

Doping Concentration

By infrared interaction of free carriers, FT-IR spectroscopy can also serve determining the doping concentration of intentionally doped semiconductors and semiconductor layers. In case of higher doping concentrations, this is often done via reflectance spectra, applying a dedicated evaluation software based on Maxwell’s equations.

Wafer Mapping

Mapping measurements can be done for wafers with Bruker research FT-IR spectrometers equipped with dedicated wafer mapping accessories. Reflectance and transmittance spectra can be automatically recorded at different sample positions, combined with layer thickness evaluation, quantitative analysis of layers and many more.