Keywords: silicon nanoporous array (Si-NPA); zinc sulfide (ZnS); field emission
In order to study the effect of substrate morphology on the cold cathode field emission performance, silicon nanoporous column array (Si-NPA) with columnar and crater-like features was used as the substrate and prepared by chemical water bath (CBD) method. Zinc sulfide (ZnS)/Si-NPA was used to study the effect of Si-NPA substrate morphology on its field emission performance by comparing the emission properties of the two samples. The results show that the ZnO nanoneedle cluster array has a lower on-field strength, a larger field enhancement factor and a higher current emission density than the ZnO nanorod cluster array. At the same time, the ZnS/Si-NPA columnar array has a lower on-field strength and a higher emission current density than the crater-like array, and the F-N curves of the two exhibit distinct characteristics. The finite element method is used to simulate the electric field distribution near the top of the array elements in the ZnS/Si-NPA columnar and crater arrays. The results show that the ZnS/Si-NPA top with columnar elements exhibits a stronger field enhancement effect. It is proved that the substrate morphology is one of the important control factors for the cold cathode field emission performance.