Preparation And Property Of High-Performance P-CuI Films

Transparent semiconductors are widely used in flat panel displays,solar cells,light emitting diodes and many other fields.It is noted that almost all commercially available transparent semiconductors show n-type conductivity.p-type TCs as an essential component employed in the active devices,their performance is far behind n-type TCs,seriously limiting the application of these active devices.As a result,improving the conductivity of p-type TCOs while maintaining their high transmittance is indeed a challenge at this moment.γ-phase cooper iodide(γ-CuI),an inexpensive and non-toxic p-type semiconductor has attracted people’s attention.However,the γ-CuI films deposited by different techniques generally possess gross grains and present a frosted-glass-like appearance.Therefore,this work investigates the preparation of CuI films by different iodination methods,and the promising solid iodination method is studied and optimised in depth.On this basis,the performance of CuI-based flexible materials with pn junctions is also investigated in this paper.Overall,this study provides a method for preparing high performance p-type conductive films and explores their application in electronics.In this study,the precursor Cu3N thin films were prepared by magnetron sputtering,followed by CuI thin films by three iodination methods:solid,liquid and gas.By analysing the microscopic morphology and optoelectronic properties of the CuI films,it was determined that the CuI films prepared by the solid iodination method had the optimal surface quality and optoelectronic properties.Then a novel strategy to fabricate γ-CuI film with truly high visible transmittance and low haze under room temperature is necessary.In the current work,the surface morphology of the CuI film can be controlled by adjusting the contact area between iodine and the CU3N precursor.The transmittance of the as-prepared γ-CuI films can be as high as 86%.The haze of the as-prepared γ-CuI films can be as low as 0.7%.Meanwhile,the asprepared CuI film possesses a FOM as high as 230 MΩ-1.In addition,this paper also used the solid iodination method to prepare CuI thin films with a permeability higher than 80%on PET substrates.The change in resistance is within 1%at±150° of bending.The p-CuI/n-ZnO heterojunction was subsequently prepared with an optical transmittance of about 80%.The pn junction has significant rectification characteristics with a rectification ratio of about 106.