Optimizing drive parameters of a nanosecond, repetitively pulsed microdischarge high power 121.6 nm source

Utilizing nanosecond high voltage pulses to drive microdischarges (MDs) at repetition rates in the vicinity of 1 MHz previously enabled increased time-averaged power deposition, peak vacuum ultraviolet (VUV) power yield, as well as time-averaged VUV power yield. Here, various pulse widths (30–250 ns), and pulse repetition rates (100 kHz–5 MHz) are utilized, and the resulting VUV yield is reported. It was observed that the use of a 50 ns pulse width, at a repetition rate of 100 kHz, provided 62 W peak VUV power and 310 mW time-averaged VUV power, with a time-averaged VUV generation efficiency of ∼1.1%. Optimization of the driving parameters resulted in 1–2 orders of magnitude increase in peak and time-averaged power when compared to low power, dc-driven MDs.