Expanded Usage Window of Molding Compound to Reduce Material Wastage in Manufacturing Line

This paper discusses about direct material wastage brought by expiring molding compound particularly for QFN-mr Packages. An Engineering problem solving methodology was used to identify the material, its consumption, cost, the root cause, and solution of the problem. The study aims to solve huge amount of compound material disposed in the manufacturing line. By challenging the current 24hours suppliers thawing time, it is shown that at 16hours thawing time, molding compound already reached the required room temperature (23°C ± 3°C). To maximize the usage window of molding compound, the existing floor life of 24hrs was also reviewed and after experiment, it was found out that it can still be extended to another 24hrs or 48hrs total floor lifetime. Combining the 2 improvements, a total of 56hrs usage window for the molding compound from 24hrs usage window.

A laser-cutting-centered STEM course for improving engineering problem-solving skills of high school students in China

<p style='text-indent:20px;'>STEM (science, technology, engineer, mathematics) education and engineering education are receiving an increasing amount of interest worldwide, but related research on the influence of STEM courses on students' engineering problem solving in China is scarce. Considering the rapid prototyping function of laser-cutting tools, this study was conducted to develop a STEM course based on laser cutting and to explore how the course affected high school students' engineering problem-solving abilities. A 9-week curriculum was implemented in a science, technology, and fabricating club of a high school in Zhejiang, China. The data were collected by pretest and posttest questionnaires and presentations of group assignments. The results were as follows. First, when presented with an engineering problem, the students demonstrated problem-solving abilities because they followed principles of engineering design, such as sketching, modeling and modifying. Second, while completing the assignment, the students proposed solutions with comprehensive factors in many aspects. They showed high-level thinking, such as consideration of the background, limiting conditions, and multidisciplinary knowledge, and they used technological tools to complete the task. However, some students ignored the assessment and redesign of their solutions. Further research could use a larger sample from different grades and explore how a STEM course combined with technology tools could influence students' high-level thinking skills.</p>