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Title: Absolute measurement of vacuum ultraviolet photon flux in an inductively coupled plasma using a Au thin film

A new method for absolute measurement of the vacuum ultraviolet (VUV) photon flux at the edge of a plasma is described. The light produced by the plasma was allowed to strike a negatively biased, gold-coated copper substrate remote from the plasma. The resulting photoelectron emission current was measured, and the absolute photon flux was then found from the known photoelectron yield of Au. The method was used to quantify the amount of VUV light produced by an Ar/He inductively coupled plasma (ICP). Strong emissions at 104.82 and 106.67 nm, corresponding to the 1s2and 1s4resonant states of Ar, were observed. The maximum, integrated VUV photon flux measured at the remote location was 3.2 × 1013 photons/cm2 s. This was estimated to correspond to a flux of 5 × 1015 photons/cm2 s at the edge of the ICP, in the range of reported values under similar conditions.

 
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NSF-PAR ID:
10363153
Author(s) / Creator(s):
 ;  ;  ;  
Publisher / Repository:
American Vacuum Society
Date Published:
Journal Name:
Journal of Vacuum Science & Technology B
Volume:
40
Issue:
2
ISSN:
2166-2746
Page Range / eLocation ID:
Article No. 022206
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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