The I-V characteristics of the PEDOT∶PSS/metal hetero-contacts with different metals of Mg, Al and Ag were investigated. It’s found that the resistivity of the Mg(Al)/PEDOT∶PSS contact is considerably high, which may play the role of an insulated layer. Based on this phenomenon, a simple lithography-free interdigitated back contact silicon solar cell using PEDOT∶PSS as the hole transport layer and LiF as the electron transport layer was designed and fabricated. During the fabrication of the solar cells, shadow mask was used only once attributed to the insulating effect of the Mg/Al/PEDOT∶PSS contact. Then a MoOx layer grown by hot wire oxidation-sublimation deposition technique was overlaid on PEDOT∶PSS and a LiF thin film with appropriate thickness was thermal evaporated into the interface between Si and Mg/Al to improve the ability of carriers collection of the device. And the interdigitated back contact silicon solar cells with a highest VOC of 592 mV and a best efficiency of 10.13% are achieved. Using metal-assisted chemical etching to prepare silicon nanowire structure which improves the effect of front surface light trapping, an interdigitated back contact solar cell with a VOC of 587 mV, a JSC of 35.57 mA/cm2, a FF of 69.97%, and an efficiency of 14.61% is fabricated.