Résumé
We present an analysis of the electronic structure of in-grown 3C and 8H stacking faults (SFs) in a 4H-SiC matrix. First, the concept of low temperature photoluminescence optical signature of SFs is discussed. Then, the results of type-II quantum well (QW) model calculations are displayed, taking into account the effect of the valence band offset, internal polarization field and non homogeneity of the potential well. In this case, we show that a satisfactory description of 3C QWs signature can be reached. The situation is entirely different for 8H. Since a 8H unit cell is nothing but two 3C lamellae coupled by an hexagonal turn, we investigate in detail the effect of coupling more and more two 3C lamellae until a final 8H QW is found. In this way, we show that a reasonable agreement with experimental data can be reached.