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The purpose of this paper is to study the effect of conformal coating on the thermal cycling reliability of anisotropically conductive adhesive film (ACF) joined flip chip components on FR‐4 and polyimide (PI) substrates.

Test chips were joined using flip chip technology and an anisotropically conductive adhesive. The conformal coating used was parylene C and it was applied using the vapour deposition polymerisation method. The reliability of ACF joined flip chip components on FR‐4 and PI substrates was evaluated using −40/+85°C thermal cycling testing. Test lots with and without parylene C coating were studied. Additionally, one test lot with initial moisture inside the coating layer and a PI substrate was subjected to the test. The reliability results were analyzed using Weibull analysis and failure analysis was performed to study the failure mechanisms using cross sectioning and optical and scanning electron microscopy.

The results show a clear difference between the FR‐4 and PI substrate materials. PI substrate material proved to be reliable enough to withstand the thermal cycling testing. Two different occurrences of the first failures are seen and analyzed with FR‐4 substrates. The conformal coating layer did not seem to impair the reliability. Parylene C coating proved to be a reliable choice to protect, and even improve, the thermal cycling reliability of flip chip devices.

Usually, conformal coatings are studied in humidity tests. However, it is also vital to know whether the conformal coatings affect the reliability in thermal cycling and there is a lack of reliability studies in this area. This paper gives reliability data for conformal coating users about the influence of thermal cycling.

The purpose of this study is to investigate the effect of chip and substrate thickness on the thermal cycling reliability of flip chip joints assembled with anisotropic conductive adhesives (ACA) on FR‐4 substrates.

Four test lots were assembled with two substrates and two test chips. The thicknesses of the substrates were 710 and 100 μm and the thicknesses of the chips were 480 and 80 μm. To study the effect of the bonding pressure each test lot contained four test series bonded with four different bonding pressures. The reliability of the test samples was studied using a temperature cycling test.

The reliability of the test lots varied widely during the test. The test lot with a thin substrate and thin chip demonstrated considerably better reliability than the other test lots. In addition, the test lots had different failure mechanisms. After the test delamination was found in every test lot except the one assembled with the thin chip and the thin substrate.

The work shows that the thermal cycling reliability of ACA flip chip joints can be markedly increased by using thinned chips or reducing the thickness of the substrate.

The purpose of this paper is to examine the long-term reliability of an anisotropic conductive adhesive (ACA) attached polyethylene terephthalate (PET) flex-on-board (FOB) assembly for industrial application used in harsh environments. In addition, the possibility of reducing reliability testing time was studied.

A−40/+125°C thermal cycling test with 5- and 14-minute soak times was used to study the reliability. To study the functionality of the FOB assembly during testing, a real-time resistance measurement was used together with a 90° peel strength test. Failure analysis was performed on samples using scanning electron microscopy and cross sectioning.

No failures or noticeable increase in the measured resistance values were seen during testing. The peel strength, however, decreased significantly with both soak times used. The highest drop in the mechanical strength occurred at the start of the temperature cycling tests. The time spent at the high temperature extreme seemed to have a greater impact on the peel strength than the number of temperature cycles. The failure mode of peel tested samples changed due to temperature cycling from interfacial delamination to cohesive failure. The temperature cycling was also observed to induce voiding inside the adhesive.

The paper illustrates the applicability of ACA attached PET flex in high reliability industrial applications. Additionally, testing methods for high reliability adhesive interconnections are discussed. Especially, the effect of temperature cycling soak time on peel test results and reliability testing time is studied.

The purpose of this paper is to investigate the effect of substrate material and thickness on the thermal cycling reliability of flip chip joints assembled with anisotropic conductive adhesives (ACA).

Four test lots are assembled using three different substrates. Two of the substrates are made of FR‐4. The thicknesses of these substrates are 600 and 100 μm. The third substrate is made of liquid crystal polymers (LCP) and is flexible. With the thicker FR‐4 substrate two test lots are assembled using both normal and two‐step bonding profiles to study how the bonding profile affects the deformation of the substrate. Four different bonding pressures are used to study the effect of pressure on reliability and the failure mechanism of the ACA joints. The reliability of the test samples is studied using a temperature cycling test.

The reliability of the test lot with the LCP substrate is considerably better than that of the test lots with the FR‐4 substrates. Additionally, the thinner FR‐4 substrate has better reliability than the thicker FR‐4 substrate. The failure mechanisms found varied among the test lots. The effect of the two‐step bonding process on the deformation of the substrate is found to be minor compared with the effect of the glass fibres.

The work shows that the thermal cycling reliability of ACA flip chip joints is markedly influenced by the thickness and material of the substrate. It is also seen that the substrate used influences the failure mechanisms formed during thermal cycling testing.

The purpose of this study is to investigate the reliability of flip chip joints made with anisotropic conductive adhesives (ACA) on flexible polyimide (PI) and liquid crystal polymer (LCP) substrates.

Six test series using two ACAs and an LCP substrate were made with varying bonding pressure. The ACAs had the same matrix and conductive particles. To lower the CTE of one of the adhesives silica had been added to it. The reliability of the test series was studied in a temperature cycling test. The purpose of these test series was to find the optimal bonding pressure for both the adhesives used. According to the results from these initial tests, further test series were made with both LCP and PI substrates. The reliability of these test samples was studied using a temperature cycling test and a constant humidity test. The adhesion strength of the joints was studied before testing.

Both substrates had excellent reliability during the temperature cycling test. However, the reliability of the PI substrates during the constant humidity test was markedly lower than that of the LCP substrates. Additionally, the adhesion strength of the adhesives on to PI substrates was clearly less.

The work shows how the substrate material used affects the reliability of flip chip joints. In addition, the work shows how the addition of silica to the ACA matrix affects the reliability of the joints.

Big data analytics (BDA) increasingly provide value to firms for robust decision making and solving business problems. The purpose of this paper is to explore information quality dynamics in big data environment linking business value, user satisfaction and firm performance.

Drawing on the appraisal-emotional response-coping framework, the authors propose a theory on information quality dynamics that helps in achieving business value, user satisfaction and firm performance with big data strategy and implementation. Information quality from BDA is conceptualized as the antecedent to the emotional response (e.g. value and satisfaction) and coping (performance). Proposed information quality dynamics are tested using data collected from 302 business analysts across various organizations in France and the USA.

The findings suggest that information quality in BDA reflects four significant dimensions: completeness, currency, format and accuracy. The overall information quality has significant, positive impact on firm performance which is mediated by business value (e.g. transactional, strategic and transformational) and user satisfaction.

On the one hand, this paper shows how to operationalize information quality, business value, satisfaction and firm performance in BDA using PLS-SEM. On the other hand, it proposes an REBUS-PLS algorithm to automatically detect three groups of users sharing the same behaviors when determining the information quality perceptions of BDA.

The study offers a set of determinants for information quality and business value in BDA projects, in order to support managers in their decision to enhance user satisfaction and firm performance.

The paper extends big data literature by offering an appraisal-emotional response-coping framework that is well fitted for information quality modeling on firm performance. The methodological novelty lies in embracing REBUS-PLS to handle unobserved heterogeneity in the sample.

The purpose of this paper is to provide a contemporary review of the research on racial disparities in police decision making.

State of the art literature review.

The findings are mixed on racial disparities in the primary policing domains of stops, arrests, use of force, and neighborhood deployment. While minorities are often overrepresented among those subjected to police enforcement actions, these findings vary considerably. Almost all of the current studies that have reported racial disparities in the exercise of police authority lack the methodological rigor or statistical precision to draw cause and effect inferences.

Efforts underway to document the impact of body-worn cameras on citizen complaints and force used by police could be extended to examine the impact of cameras on racial disparities in other enforcement-related outcomes such as arrests, stops and frisks, or searches. In addition, evaluating the effects of police training, such as anti-bias training or training on police legitimacy, on reducing racial disparities in police enforcement outcomes is another promising line of research inquiry.

This paper provides a concise review of the current state of the literature on a topic that is dominating the national conversation currently underway about the role of the police in American society.

The purpose of this paper is to explore the association between Mexicans’ support for the criminalization of immigration and level of police contact, fear of deportation and the perceived personal impact of immigration enforcement.

This analysis uses data from the 2008 National Survey of Latinos, a representative random sample of 1,153 self-identified Latino/as residing in the USA. The authors sought to identify the prevalence of Latino support for local police actively identifying undocumented immigrants and to examine the relationship between acculturation, confidence in the police and/or fear that immigrants increase neighborhood crime and support for the criminalization of immigration. The authors use logistic regression analysis and post-estimation techniques to explore the relationship between support for the criminalization of immigration and acculturation, discrimination, perceptions of crime and confidence in the police.

The authors found that Latino policy attitudes are not monolithic but differ by nativity and citizenship status and vary according to their level of confidence in fair and proper police enforcement of the law. Within levels of confidence, the authors found that the perception that immigrants increase local crime rates was a significant predictor of policy attitudes. Contrary to the authors’ expectations, neither previous contact with the criminal justice system nor being stopped and asked about immigration status predicted support for criminalizing immigration. Nor did level of support vary according to proficiency in English and perceptions of discriminatory treatment.

This study has implications for understanding how citizenship statuses influence public opinion on issues that are presumed to be reflective of a unified political voice.

This study has implications for understanding the role of social stigma and political socialization and their relationship to Mexican citizens and non-citizens policy preferences.

No study to date has explored associations between Latinos’ policy attitudes on the criminalization of immigration and acculturation, fear of crime and confidence in the police.