Flexible p-type PEDOT:PSS/a-Si:H hybrid thin film solar cells with boron-doped interlayer

•p-Type PEDOT:PSS windows were used for flexible a-Si:H thin film PV cells.•PEDOT:PSS should be free from a damage caused by subsequent deposition process.•Surfactant addition and H2-treatment improve the adhesion of PEDOT:PSS on a-Si:H.•Insertion of highly B-doped Si leads to further improvement in cell performances.•Cell with PEDOT:PSS showed higher flexibility than cell with p-type μc-Si:H particularly at bending radius < 10 mm.