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Semiconductor packaging industry has in recent years tightened the tolerance criteria for acceptable solder void size in the semiconductor packages due to the high usage in automotive applications. Semiconductor packaging component makers have strengthened the quality of the solder joint and its electrical conductivity by controlling the maximum solder void size reduction from 10-15% to 5% or below over die size. This paper aims to reduce the solder void size to minimum level that current industry could not achieve and introduce a new soldering processes by combining vacuum reflow and pressure cure to effectively reduce solder void.

This study is using the empirical data collection to prove the feasible in achieve the goal. It is an engineering approach. This research study is even considering sufficient data (>22 units) in each evaluation to represent the actual performance.

Successfully eliminate all the hollow solder void that current industry claimed as solder void. EDX analysis showed that the compressed solder voids remained in the solder are filled with solid carbon-based substances which could be originated from the trapped flux residues. It is empirical data proven in feasibility stage.

The study is able to produce solder void-less. This method is suitable for high volume manufacturing process also. This may lead a new pave way for industry to resolve solder void problem. The current pressure cure machine could not apply more than 200°C temperature which limits medium and high temperature solder paste or alloy testing. Therefore, only low temperature solder alloy Pb37Sn63 was able to be evaluated.

This study is original and has not been published elsewhere to produce high efficiency product in semiconductor packaging performance in electrical path and heat dissipation. It also improves package reliability due to solder joint used as interconnect in semiconductor packaging.

The paper aims to explore the road to independence of the less-fortunate women in early Hong Kong society and their means in passing of wealth after death. In the 1970s, about 400 Chinese wills from the 1840s to the 1940s were dug up on a construction site in Hong Kong. One-fourth of these were from women who had held a substantial amount of property. How they obtained this property intrigued us because, at that time, women were seen as subordinate to men and excluded from the labor market. Why they had wills led to further questions about Hong Kong society of that time and the role of women in it.

The analysis of this paper is based on archival data gathered from the Hong Kong Public Records Office. These data include 98 women’s wills filed from the 1840s to the 1940s and a 500-page government investigation report on the prostitution industry released in 1879. The former recorded valuable information of brief testators’ family and personal life history, amount of assets, and profolio of investment, etc. The latter included testimonials of brothel keepers and prostitutes and their life stories and the background of legalizing prostitution in early Hong Kong. Apart from basic quantitative analysis on women’s marital status, number of properties, nature of wills and number of brothels, qualitative analysis is directed to review the testator’s life of self-reliance, wealth accumulation and reasons of using wills for arranging wealth transmission after death.

In this paper, the authors found that because the colonial government declared prostitution legal, and only women could obtain employment by becoming prostitutes or brothel keepers, they earned their own livelihood, saved money and finally became independent. However, because these professions were not seen as “decent”, and these women were excluded from the formal marriage system, intestacy could cause problems for them. Through their socio-business connections, they became familiar with the Western concept of testate inheritance. So, they tended to use wills – a legal document by which a person assigns someone to distribute his or her property according to his or her wishes after his or her death – to assign their property.

Because only archival data are chosen for analysis, the research results may lack generalizability. Follow-up researches to examine whether the studied women acquired their wealth through their own work or simply as gifts from others are required.

This paper explores the understudied women’s life and method of estate passing after death in the early Hong Kong society. It fills the academic gap of women’s contribution to Hong Kong’s success and enriches our understanding on the important factors that could attribute women’s real independence.