Impact of Gliding Arc Discharge Plasma on Physical, Optical, and Electrical Properties of ZnO Thin Film

ABSTRACT Atmospheric‐pressure Gliding Arc Discharge Plasma (GADP) offers a scalable, vacuum‐free method for enhancing ZnO thin films. A 6‐min GADP treatment yields notable improvements over untreated samples, reducing nanorod diameters by 79%, increasing oxygen content by 20%, and narrowing the optical bandgap from 3.20 eV to 3.12 eV. Plasma‐generated reactive species induce surface modifications, enhancing crystallinity and passivating deep‐level defects while introducing shallow oxygen vacancies. This results in a sixfold increase in electrical conductivity. Structural improvements are confirmed by reduced micro‐strain and sharper Raman E2 (high) peaks. Wettability also improves, with contact angles dropping from 61° to 42°. These findings establish GADP as a versatile technique for ambient‐condition engineering of ZnO for optoelectronics, sensors, and flexible devices.