{'fraction_non_alphanumeric': 0.02849002849002849, 'fraction_numerical': 0.00949667616334283, 'mean_word_length': 4.5473684210526315, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Ashing Properties in a Surface-Wave Mode Plasma with a High-Permittivity Alumina Window

Ashing properties in a surface-wave mode at 133 Pa and 1 kW with an alumina disk-plate window are investigated by comparison of those in a volume mode with a quartz disk-plate window. In the surface-wave mode, plasma is confined to the alumina window surface area and ashing in a downstream area is carried out mainly by atomic oxygen. The ashing activation energy of 0.42 eV in the surface-wave mode ashing is comparable to 0.5 eV with an ashing condition by atomic oxygen at the ground state [O(3P)](the so-called downstream state). These results indicate that the plasma in the surface-wave mode can realize a downstream ashing condition. On the other hand, ashing with a quartz window was done by plasma, where the activation energy is influenced by built-in high-frequency magnetic field. Moreover, the ashing rate distribution in the surface-wave mode characterized with the alumina window is more uniform than that in the volume mode with the quartz window.