Electron Magnetic Susceptibility, Paramagnetic Resonance, and the Band Structure of Silicon‐Rich n‐Type Silicon–Germanium Alloys

The lattice susceptibility appropriate to the silicon content has been subtracted from the total susceptibility. The remaining carrier contribution is dependent on the effective mass parameters and the g ‐value. Using g ≈ 2, extrapolated from measured electron paramagnetic resonance (EPR) values and assuming six ellipsoidal energy surfaces with K = m ∥/ m ⟂ = 4.68, the mass m ⟂ is found to be about m ⟂ = 0.27 m ( m free electron mass), a value lying close to that for silicon. This result indicates that the band structure as a whole in the neighbourhood of the Δ 1 minimum changes only slightly going from 100% silicon to the range between 80 and 65% silicon in silicon–germanium alloys.