Comparative Analysis of HV Bipolar and Unipolar Drives for DBD-Based 222 nm Excilamp

Dielectric-barrier discharge (DBD) excimer lamps emitting at 222 nm are increasingly utilized in applications such as surface decontamination, UV-C curing, and medical sterilization. Despite their growing adoption, the influence of drive topology on lamp performance remains underexplored. This study presents a systematic experimental comparison between unipolar and bipolar high-voltage pulse modulators driving identical fused-silica 222 nm DBD lamps. Key performance metrics including pulse energy, ultraviolet (UV) intensity, DBD dynamic capacitance, discharge current, breakdown voltage, and pulse timing jitter are evaluated across five DBD voltage levels. Timing jitter is statistically analyzed over 40 consecutive discharge events per configuration. At a peak DBD voltage of 6.5 kV, the bipolar modulator delivers 116.98% higher average pulse energy (1.15 versus 0.53 mJ) and 278.65% greater 222 nm UV intensity (6.10 versus 1.611 mW/cm2) compared to the unipolar counterpart. The bipolar drive exhibits 32% higher average dynamic capacitance (21.36 versus 16.18 pF), suggesting enhanced discharge coupling. These findings highlight the significant performance advantages of bipolar modulation for driving 222 nm DBD excimer lamps and support its use in high-efficiency, high-throughput UV-C systems.