A field programmable gate array based Langmuir probe system for measurement of plasma parameters at 500 kHz in a high-power impulse magnetron sputtering plasma

C J Hickling; S Hall; J R Harrison; R Sharples; J W Bradley

doi:10.1063/5.0174458

A field programmable gate array based Langmuir probe system for measurement of plasma parameters at 500 kHz in a high-power impulse magnetron sputtering plasma

Rev Sci Instrum. 2024 Mar 1;95(3):033503. doi: 10.1063/5.0174458.

Authors

C J Hickling^{1

2}, S Hall², J R Harrison², R Sharples³, J W Bradley¹

Affiliations

¹ Department of Electrical Engineering and Electronics, University of Liverpool, Brownlow Hill, Liverpool L69 3GJ, United Kingdom.
² UK Atomic Energy Authority, Culham Science Centre, Abingdon, Oxfordshire OX14 3DB, United Kingdom.
³ Department of Physics, Durham University, Lower Mountjoy, South Road, Durham DH1 3LE, United Kingdom.

PMID: 38497837
DOI: 10.1063/5.0174458

Abstract

By utilizing Field Programmable Gate Arrays in a configuration similar to that of the Mirror Langmuir Probe, it is possible to bias a single probe at three precise voltages in sequence. These voltages can be dynamically adjusted in real-time based on the measured plasma electron temperature to ensure the transition region is always sampled. The first results have been obtained by employing this method and have generated real-time outputs of electron temperature, ion saturation current, and floating potential on a low temperature pulsed-DC magnetron at 500 kHz. These results are in good agreement with the analysis of a conventionally swept Langmuir probe. This probe is designed with the intention of being implemented on MAST-U to aid in the study of exhaust physics and enable further investigation into filamentary behavior.