A new B-dot probe circuit for magnetic diagnostics of radio frequency discharges.
Rev Sci Instrum
; 89(10): 105104, 2018 Oct.
Article
en En
| MEDLINE
| ID: mdl-30399790
ABSTRACT
Accurate magnetic measurements in radio frequency capacitively coupled plasmas (CCP) are challenging due to the presence of inherently strong electric fields and relatively weak magnetic fields. In this work, a new B-dot probe circuit is presented, comprising two variable capacitors in a tunable series resonance circuit, with a center-tapped, step-up transformer. The output characteristics of the probe are predicted using two distinct equivalent circuit models, one for the differential mode and the other for the common mode. A Helmholtz coil and a Faraday cup are used for experimental validation of the predicted probe output. By tuning the two variable capacitors in the circuit, the magnetic probe can achieve improved signal-to-noise ratio by amplifying the inductive signal, while suppressing capacitive coupling interference. Using the newly designed probe, magnetic measurements in typical CCP are presented.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Tipo de estudio:
Diagnostic_studies
/
Prognostic_studies
Idioma:
En
Revista:
Rev Sci Instrum
Año:
2018
Tipo del documento:
Article
País de afiliación:
China