Copper iodide has emerged as a p-type semiconductor for solution-processed thin-film transistors (TFTs) owing to high hole mobility. Zn-doped Copper iodide (Zn:CuI) thin films were fabricated as p-type semiconductors for solution-processed thin-film transistors (TFTs) using a combination of spin and spray coating. To enhance stability, the hydrophobic fluoropolymer CYTOP was applied as a passivation layer on the Zn:CuI films. CYTOP effectively blocked oxygen penetration, verified by the chemical binding energy analysis. The resulting TFTs showed improved performance with low off-state current and normal threshold voltage. Additionally, conventional planar and monolithic 3D vertical complementary inverters were then constructed on a single wafer using a n-type In2O3/ZnO bilayer and p-type Zn:CuI films.