Defects in highly N-doped 4H-SiC deformed by cantilever bending at 550C were identified by weak-beam and high-resolution transmission electron microscopy techniques. The induced-defects consist of double stacking-faults whose expansion produces a local 4H → 3C phase transformation. Each double stacking-fault was bound by 2 identical 30° Si(g) partial dislocations which glided on 2 adjacent basal planes. The double stacking-faults belonged to 3 different populations which differed by their extension as a function of the applied stress and the 30° Si(g) characteristics (line direction , Burgers vector, glide plane and glide direction). The external mechanical stresses were the main driving forces involved in the double stacking-fault expansion. However, extra driving forces such as thermodynamic or electronic forces were also likely to be involved.Structural Characterization of Double Stacking Faults Induced by Cantilever Bending in Nitrogen-Doped 4H-SiC. G.Regula, M.Lancin, H.Idrissi, B.Pichaud, J.Douin: Philosophical Magazine Letters, 2005, 85[5], 259-67

Figure 7

Diffusivity of B in SiGe

(from the top: pure SiGe with interstitial injection, C-doped SiGe with interstitial

injection, pure SiGe with no injection, C-doped SiGe with no injection)