Second Harmonic Generation characterization of SOI wafers: Impact of layer thickness and interface electric field

•SHG is investigated as a non-destructive characterization method for SOI materials.•For thick SOI, SHG is related to the thickness variations of the different layers.•In thin SOI, a supplementary SHG contribution exists, attributed to the dc fields at the interfaces.•The impact of the electric field at each interface of the SOI is assessed.•SHG can be used to evaluate interfacial electric fields in SOI materials.