UC Berkeley

Atmospheric pressure plasma jets (APPJs) are increasingly used in plasma medicine and materials processing applications. Reproducible and effective operation of APPJs requires regulating the cumulative effects of plasma on a target substrate in the face of variabilities and exogenous disturbances. This article investigates spatial delivery of thermal effects - thermal dose - of plasma using a kHz-excited APPJ in helium translated over a dielectric substrate. A dose metric is presented for quantifying the cumulative, nonlinear thermal effects of plasma along the translation trajectory of the APPJ. An optimization-based feedback control strategy is proposed for real-time regulation of thermal dose delivery using spatial measurements of substrate temperature. Experimental investigation reveals that feedback control is crucial for achieving spatially uniform dose delivery.