In this investigation, we studied the interdiffusion behavior between polycrystalline silicon (poly-Si) and aluminum where the poly-Si was doped with antimony via ion implantation. Post sintering sample microstructure was determined by Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), and optical microscopy, and composition was determined by Rutherford Backscattering Spectrometry (RBS) and Scanning Auger Microscopy. As-implanted samples showed interdiffusion during sintering (465° C, dry N2) independent of Sb concentrations up to 1.1 × 1021 cm-3 near the Al/Si interface. In samples where the implantation damage was annealed out prior to sintering, interdiffusion is inhibited when the Sb concentration at the interface was above a threshold concentration of 7.3 × 1019 cm-3. This threshold concentration is lower if the segregation of Sb is preserved prior to metallization. We propose that interdiffusion is inhibited by dopant (Sb) passivation of interfacial Si defects, the sites where interdiffusion is believed to initiate.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering
- Materials Chemistry