Chemical sputtering yield of pyrolytic graphite bombarded with 3 keV H3+ under atomic hydrogen atmosphere

Low-temperature post-oxidation annealing (POA) process of high-reliability thermal oxides grown on 4H-SiC using new apparatus that generates atomic hydrogen radicals by high-temperature catalyzer has been investigated. Atomic hydrogen radicals were generated by thermal decomposition of H2 gas at the catalyzer surface heated at high temperature of 1800°C, and then exposed to the sample at 500°C in reactor pressure of 20 Pa. The mode and maximum values of field-to-breakdown are 11.0 and 11.2 MV/cm, respectively, for the atomic hydrogen radical exposed sample. In addition, the charge-to-breakdown at 63% cumulative failure of the thermal oxides for atomic hydrogen radical exposed sample was 0.51 C/cm2, which was higher than that annealed at 800°C in hydrogen atmosphere (0.39 C/cm2). Consequently, the atomic hydrogen radical exposure at 500°C has remarkably improved the reliability of thermal oxides on 4H-SiC wafer, and is the same effect with high-temperature hydrogen POA at 800°C.

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Chemical sputtering of carbon by combined exposure to nitrogen ions and atomic hydrogen

New Journal of Physics ◽

10.1088/1367-2630/10/5/053037 ◽

2008 ◽

Vol 10 (5) ◽

pp. 053037 ◽

Cited By ~ 17

Author(s):

M Schlüter ◽

C Hopf ◽

W Jacob

Keyword(s):

Atomic Hydrogen ◽

Combined Exposure ◽

Chemical Sputtering ◽

Nitrogen Ions

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Chemical sputtering of carbon by sub‐eV atomic hydrogen: New results and a critical comparison with previous data relevant to fusion applications

Journal of Vacuum Science & Technology A Vacuum Surfaces and Films ◽

10.1116/1.572034 ◽

1983 ◽

Vol 1 (3) ◽

pp. 1425-1429 ◽

Cited By ~ 28

Author(s):

P. C. Stangeby ◽

O. Auciello ◽

A. A. Haasz

Keyword(s):

Atomic Hydrogen ◽

Critical Comparison ◽

Chemical Sputtering ◽

Fusion Applications

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The emission rates of CH, CD and C2spectral bands and a re-evaluation of the chemical sputtering yield of the JT-60U carbon divertor plates

Nuclear Fusion ◽

10.1088/0029-5515/54/4/043004 ◽

2014 ◽

Vol 54 (4) ◽

pp. 043004 ◽

Cited By ~ 1

Author(s):

T. Nakano ◽

S. Higashijima ◽

H. Kubo ◽

N. Asakura ◽

M. Fukumoto

Keyword(s):

Emission Rates ◽

Chemical Sputtering ◽

Sputtering Yield ◽

Divertor Plates

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Retention of Hydrogen in Well-Ordered Pyrolytic Graphite as a Result of its Interaction with Atomic Hydrogen

Physica Scripta ◽

10.1238/physica.topical.103a00043 ◽

2003 ◽

Vol T103 (1) ◽

pp. 43

Author(s):

E. A. Denisov ◽

T.N. Kompaniets ◽

K. L. Kostyushkin ◽

I. V. Makarenko ◽

A. N. Titkov

Keyword(s):

Atomic Hydrogen ◽

Pyrolytic Graphite

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Surface Luminescence of Polycrystalline Zinc Oxide Excited by Hydrogen Atoms

MRS Proceedings ◽

10.1557/proc-0957-k07-02 ◽

2006 ◽

Vol 957 ◽

Author(s):

Michael Sushchikh ◽

Vladislav Styrov ◽

Vladimir Tyutunnikov ◽

Nick Cordella

Keyword(s):

Atomic Hydrogen ◽

Hydrogen Atmosphere ◽

Adsorbed Hydrogen ◽

Hydrogen Atoms ◽

Long Wavelength ◽

Pl Spectra ◽

Zno Powders ◽

Exothermic Chemical Reaction ◽

Heterogeneous Chemiluminescence ◽

Surface Luminescence

ABSTRACTExcitation of a luminescence by highly exothermic chemical reaction on the surface of a luminophore provides a unique opportunity to separate surface luminescence from the bulk luminescence. This enables studies of the electronic properties of the semiconductor surfaces even if the surfaces are of complicate shapes. We have studied heterogeneous chemiluminescence (HCL) of ZnO powders. The luminescence was excited by a release of chemical energy, namely by catalytic recombination of hydrogen atoms. The HCL spectra were compared to the photoluminescence (PL) spectra. The HCL spectra were sensitive to the details of preparation and treatment whereas PL spectra almost did not change. HCL spectra of powder samples pretreated for enhancing “green” luminescence exhibited long-wavelength tail (up to 800 nm) and their maximum was blue-shifted as compared with PL spectra. Different HCL bands forming long-wavelength tail were isolated by changing the temperature of the samples. Additional milling of ZnO led to amplification of the HCL-specific surface bands. Pure ZnO showed neither PL nor HCL; however we were able to observe HCL surface bands with maxima at 610 nm and 730 nm after treatment of the sample in atomic hydrogen atmosphere at 570 K. Remarkably, such treatment did not cause appearance of the PL. The HCL in the presence of atomic hydrogen was steady in time and was caused by an abstraction of adsorbed hydrogen by incident hydrogen atoms, i.e. the reaction followed Eley-Rideal mechanism. The HCL can be utilized for in situ monitoring of the growth and evolution of ZnO in controlled atmosphere.

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