The usefulness of Transmission Electron Microscopy (TEM) for the fabrication of high-performance textured amorphous/crystalline silicon (a-Si:H/c-Si) heterojunction (HJ) solar cells is demonstrated. The classical characterization techniques used to monitor the a-Si:H layers properties incorporated into flat HJ solar cells with high open-circuit voltages up to VOC=710 mV and electrical conversion efficiencies up to