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An investigation has been performed on the improved solder wettability of oxidized aluminum (Al) with lead-free solder (96.5Sn-3.5Ag) using Ar-H₂ plasmas. The lead-free solder wettability was raised from 62.2 per cent wetting for Al oxidized in air at 250 C for 4 h to 98.4 per cent wetting of oxidized Al modified by Ar-H₂ plasmas at a certain H₂ flow rate. This study aims to gain insight on the surface characteristics of Al affecting the solder wettability with a liquid lead-free solder.

Ar-H₂ plasmas at certain H₂ flow rates are intended to reduce Al oxides on the surfaces of oxidized Al substrates both by physical bombardments via Ar plasmas and chemical reductions with H₂ plasmas, while Al substrates are exposed in Ar-H₂ plasmas to improve the solder wettability with a liquid lead-free solder.

Surface characteristics of oxidized Al substrates have been identified to play key roles for enhanced lead-free solder wettability using Ar-H₂ plasmas. A decrease in polar surface free energy and an increase in dispersive surface free energy on the surfaces of oxidized Al substrates are exploited to advance the lead-free solder wettability. Decreased composition ratios of O to Al, detected by X-ray photoelectron spectroscopy (XPS) for oxidized Al substrates, are crucial for improved lead-free solder wettability.

XPS is typically used to analyze the surface compositions of Al oxides. To provide a rapid and non-expansive method to identify the surfaces of Al substrates prior to soldering to assure lead-free solder wettability, this study proposes a measurable skill, a so-called sessile drop test method, to investigate surface free energies such as total, polar and dispersive surface free energy on the surfaces of Al substrates, to illuminate how the lead-free solder wettability of oxidized Al is improved by Ar-H₂ plasmas.

This article was based on the information from The 5th International Conference of Institutes and Libraries for Chinese Overseas Studies held in the University of British Columbia in Vancouver, BC, Canada in which the author was a presenter in session 4.2.9a of the Early life of Yuan Shikai and the formation of Yuan family. The paper aims to include comprehensive analysis and development of the history of Chinese migration. An annotated bibliography of suggested readings was offered to highlight the subject knowledge for further research in this area.

The paper includes comprehensive analysis and development of the history of Chinese migration and the experiences and family histories of overseas Chinese in Canada. An annotated bibliography of suggested readings was offered to highlight the subject knowledge for further research in this area.

The paper offers full description and comprehensive analysis of the history of Chinese migration and overseas Chinese studies in Canada. A bbibliography of suggested readings was offered for further research in this area.

This research study has a strong subject focus on Chinese migration, overseas Chinese studies, and resource-sharing in the subject area. It is a specific field for research in Asian studies.

The result of this study will assist students, researchers, and the general public in the area of overseas Chinese studies and developing their interests in the social and historical value of Chinese migration history and resource-sharing in the area.

Very little research has been done in the area of Chinese migration and historical development. The paper would offer historians, sociologists, ethnologists, librarians, administrations, professors, as well as students in the fields of Asian history, anthropology, sociology, political science, geography, and other Asian-related interdisciplinary studies.