Experimental and Numerical Characterization of Dielectric Barrier Discharge-Based Coaxial Kr/Cl Excilamp

• Published in: IEEE transactions on plasma science 2023-12, p.1-7
• Main Authors: Bidawat, Surbhi, Sharma, Navin Kumar, Singh, Mahendra, Mishra, Alok, Lamba, Ram Prakash, Choyal, Yaduvendra, Pal, Udit Narayan
• Format: Article
• Language: English
• Subjects: Chlorine; Dielectric barrier discharge (DBD); Dielectrics; Discharges (electric); Electrodes; Electron tubes; excilamp; excimers; far ultraviolet (UV)-C; incoherent radiation; Mathematical models; Voltage measurement
• ISSN: 0093-3813; 1939-9375
• DOI: 10.1109/TPS.2023.3337631

In this article, experimental and numerical characterization of a dielectric barrier discharge (DBD)-based coaxial Kr/Cl _{2} excilamp excited by negative unipolar pulse has been carried out. The typical V - I characteristics have been measured, which is further utilized to determine the average power deposited in the excilamp. It is found that the average power of 11.4 W has been deposited in the excilamp filled with the Kr/Cl _{2} mixture in the proportion of 99:1 at 100 mbar, creating microdischarges within the discharge region. The discharge mode of the excilamp is observed to be filamentary in nature. The intense emission of the 222-nm radiation is clearly shown in the spectra due to the transition of KrCl ^{\ast} excimer from B to X state. The effect of different proportions of chlorine concentration (0.1%-5%) and total pressure of the Kr/Cl _{2} mixture (25-200 mbar) have been analyzed, which mainly influences the plasma chemistry during the discharge. It has been observed that a higher percentage of chlorine (1%-5%) with a total pressure range of 25-100-mbar results in a high peak intensity of 222-nm radiation. Other kinetic processes participating in excimer formation have also been analyzed by evaluating the density of electrons, Kr ^{+} , Kr _{2}^{+} , Cl ^{-} , and Kr ^{\ast} created during the pulsed discharge, which has principally contributed to the formation of KrCl ^{\ast} excimer. This qualitative analysis is very useful for the design and development of suitable 222-nm excimer sources required for the effective inactivati