Passivation quality is mainly governed by epitaxial growth of crystalline silicon wafer surface. Void-rich intrinsic a- Si:H interfacial layer could offer higher resistivity of the c-Si surface and hence a better device efficiency as well. To reduce the resistivity of the contact area, a modification of void-rich intrinsic layer of a-Si:H towards more ordered state with a higher density is adopted by adapting its thickness and reducing its series resistance significantly, but it slightly decreases passivation quality. Higher resistance is not dominated by asymmetric effects like different band offsets for electrons or holes. In this study, multilayer of intrinsic a-Si:H layers were used. The first one with a void-rich was a-Si:H(I₁) and the next one a-SiO_x:H(I₂) were used, where a-SiO_x:H(I₂) had relatively larger band gap of ~2.07 eV than that of a-Si:H (I₁). Using a-SiO_x:H as I₂ layer was expected to increase transparency, which could lead to an easy carrier transport. Also, higher implied voltage than the conventional structure was expected. This means that the a-SiO_x:H could be a promising material for a high-quality passivation of c-Si. In addition, the i-a-SiO_x:H microstructure can help the carrier transportation through tunneling and thermal emission.

Herein, we report the fabrication of low-voltage N-type organic field-effect transistors by using high capacitance fluorinated polymer gate dielectrics such as P(VDF-TrFE), P(VDF-TrFE-CTFE), and P(VDF-TrFE-CFE). Electronwithdrawing functional groups in PVDF-based polymers typically cause the depletion of negative charge carriers and a high contact resistance in N-channel organic semiconductors. Therefore, we incorporated intermediate layers of a low-k polymerto prevent the formation of a direct interface between PVDF-based gate insulators and the semiconducting active layer. Consequently, electron depletion is inhibited, and the high charge resistance between the semiconductor and source/drain electrodes is remarkably improved by the in corporation of solution-processed charge injection layers.