ModuleWorks (Romania)

A critical review of literature was conducted to examine the student's motivation level in science subject using Augmented Reality (AR). Augmented Reality technology is used widely because it allows enhancing the understanding of complex concept at most educational levels. The two main primary approaches used to review of literature are the topical and critical review approaches. This article mainly discusses about the critical review that was carried out using 5 steps method. The methods are (1) exhibiting a research objective and research question, (2) evaluating sample of sources in the literature observed, (3) analyzing the data that was collected, (4) interpreting the findings from critical analysis using descriptive statistics and finally, (5) discussing effects and implications from these results that were identified. The author collected total number of 45 articles from index journal and 14 articles are chosen after sorting. The critical review made the author to determine 4 main themes which were constructed into a conceptual framework based on continuity. This critical review gives benefit to learners to improve the level of motivation in learning using AR. Overall, the result shows Augmented Reality in teacher education is considered very valuable and should be implemented in pedagogical problem-solving skills, such as mathematics, physics, chemistry and biology in future studies.

ABSTRACT Solder voiding in Ball Grid Array (BGA) package solder joints may compromise the solder joint integrity depending on the extent, size and location of the solder voids. This is especially true in cases where the size of the solder void is greater than 25% of the area of the solder joint, after assembling the component on to a Printed Circuit Board Assembly (PCBA), and is located at the pad interface of the solder joint. Constraints in the real estate area and move towards fine pitch array are some of the reasons warranting the use of via-in-pad designs. A concern associated with via-in-pad design is entrapped air within the micro via. The entrapped air has been shown to lead to the formation of solder voids. Filling and over plating the via (capping) is one way of preventing air entrapment within the micro via. Formations of large solder voids in (non-micro) via-in-pad designs, which are plugged with resin and capped, however, is another concern that needs to be investigated. This research paper explores the effect of factors such as the density or number of vias present within the given area array, via capping thickness, via plugging material, surface finish & baking on the formation of large solder voids in via-in-pad BGAs. Through a series of design of experiments the effect the different levels, for each of the factor, has on the solder void formation has been studied. Based on the results from these experiments guidelines to prevent the formation of large voids in via-in-pad ball grid arrays have been established and presented in this paper.