Predictive estimation of vacuum ultraviolet emission intensity in a low-pressure inductively coupled hydrogen plasma based on the branching ratio technique

다국어 초록 (Multilingual Abstract)

Vacuum ultraviolet (VUV) emission has recently attracted attention in low pressure processing plasmas because of the possibility of high-energy photon damages on the substrates. To quantify the VUV induced damages during the plasma processes, it is need to use of a VUV spectrometer equipped with vacuum systems not readily available in industries. In this work, therefore, we report a simple method to estimate the VUV emission intensity of hydrogen plasmas utilizing a conventional visible spectrometer widely used in plasma processes. From the measurement of hydrogen emission spectra in the visible wavelength region, the VUV emission line (Lyman-β) was calculated using the branching ratio technique and enabled the estimation of Lyman-α emission intensity based on the Boltzmann relation with given plasma parameters. In addition, it was found that the method could also predict the VUV emission intensity for high density hydrogen plasma cases by considering the selfabsorption effect by hydrogen atoms.

참고문헌 (Reference)

1 Luxherta Buzi, "Utilizing photosensitive polymers to evaluate UV radiation exposures in different plasma chamber configurations" American Vacuum Society 38 (38): 033006-, 2020

2 C. G. N. Lee, "The grand challenges of plasma etching : a manufacturing perspective" 47 : 273001-, 2014

3 Hyungjoo Shin, "Surprising importance of photo-assisted etching of silicon in chlorine-containing plasmas" American Vacuum Society 30 (30): 021306-, 2012

4 D. T. Clark, "Surface modification by plasma techniques. I. The interactions of a hydrogen plasma with fluoropolymer surfaces" Wiley 25 (25): 2643-2664, 1987

5 A. Vesel, "Reduction of thin oxide films on tungsten substrate with highly reactive cold hydrogen plasma" 42 : 1168-1171, 2010

6 U. Fantz, "Quantification of the VUV radiation in low pressure hydrogen and nitrogen plasmas" 25 : 045006-, 2016

7 J. L. Lauer, "Plasma and vacuum ultraviolet induced charging of SiO 2 and HfO 2 patterned structures" American Vacuum Society 30 (30): 01A109-, 2012

8 Dmitry V. Lopaev, "Photoabsorption and damage of OSG low-k films by VUV emission at 140-160 nm" Wiley 15 (15): 2-7, 2018

9 A. Kramida, "NIST ASD team, Wavelength and transition probability of hydrogen atomic spectral series" 5 (5): 2020

10 E. J. Iglesias, "In situ measurement of VUV/UV radiation from low-pressure microwave-produced plasma in Ar/O2 gas mixtures" 28 : 085501-, 2017

11 M. R. Baklanov, "Impact of VUV photons on SiO 2 and organosilicate low-k dielectrics: General behavior, practical applications, and atomic models" AIP Publishing 6 (6): 011301-, 2019

12 H. Sinha, "Effects of vacuum ultraviolet radiation on deposited and ultraviolet-cured low-k porous organosilicate glass" American Vacuum Society 29 (29): 030602-, 2011

13 M. J. Titus, "Effects of vacuum ultraviolet photons, ion energy and substrate temperature on line width roughness and RMS surface roughness of patterned 193nm photoresist" 44 : 085204-, 2011

14 Hiroyuki Miyazoe, "Effects of ultraviolet and vacuum ultraviolet synchrotron radiation on organic underlayers to modulate line-edge roughness of fine-pitch poly-silicon patterns" American Vacuum Society 35 (35): 05C306-, 2017

15 P. Marsik, "Effect of ultraviolet curing wavelength on low-k dielectric material properties and plasma damage resistance" 519 : 3619-3626, 2011

16 Dane Lojen, "Effect of VUV radiation and reactive hydrogen atoms on depletion of fluorine from polytetrafluoroethylene surface" Elsevier BV 533 : 147356-, 2020

17 J. L. Shohet, "Damage to low-k porous organosilicate glass from vacuum-ultraviolet irradiation, Damage to VUV, EUV" 8077 : 80770S-, 2011

18 P. Tian, "Controlling VUV photon fluxes in pulsed inductively coupled Ar/Cl2 plasmas and potential applications in plasma etching" 26 : 024005-, 2017

19 S. Y. Moon, "Characteristics of an atmospheric microwave-induced plasma generated in ambient air by an argon discharge excited in an open-ended dielectric discharge tube" 9 : 4045-, 2002

20 S. U. Engelmann, "Challenges of Tailoring Surface Chemistry and Plasma/Surface Interactions to Advance Atomic Layer Etching" The Electrochemical Society 4 (4): N5054-N5060, 2015

21 J.Z. Klose, "Branching ratio technique for vacuum UV radiance calibrations: Extensions and a comprehensive data set" Elsevier BV 42 (42): 337-353, 1989

22 조덕균, "Absolute density measurement of hydrogen atom in inductively coupled Ar/ H2 plasmas using vacuum ultraviolet absorption spectroscopy" 한국물리학회 20 (20): 550-556, 2020