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The purpose of this paper is to demonstrate laser microvia drilling of polyimide thin films from multiple sources before metallic sputtering. This process flow reduces Flexible Printed Circuit Board (FPCB) material, chemical and operational costs by 90 per cent in the construction of flexible circuits.

The UV laser percussion drilling of microvias in 25 μm thick polyimide films with low coefficients of thermal expansion (CTE) and elastic modulii was investigated. Results were obtained using Scanning Electron Microscopy and Surface Profilometry. Polyimide films tested included: Dupont™ Kapton^® EN; Kolon^® GP and LV; Apical^® NPI; and Taimide™ TA‐T.

There was no direct relationship between the top and bottom diameters and ablation depth rates between the polyimide films tested using the same test conditions. There was a direct relationship with exit diameters and etch rates at different laser pulse frequency rates and fluence levels. Laser pulse rates at 30 kHz produced 20 per cent larger exit diameters than at 70 kHz, however at 70 kHz the first pulse etched 16.5 per cent more material. High fluence levels etched more material but with a lower etch efficiency rate. Other microvia quality concerns such as surface swelling, membrane residues on the bottom side and surface debris inside the microvias were observed. Nanoscale powder‐like surface debris was observed on all samples in all test conditions.

This is the first comparison of material specifications and costs for films from multiple polyimide manufactures and laser microvia drilling. The paper also is the first to demonstrate results using a JDSU™ Lightwave Q302^® laser rail. The results provide the first insights into potential microvia membrane issues and debris characteristics.

This paper aims to assess the relationship between oil price and inflation in the Organization for Economic Co-operation and Development (OECD) countries. This paper contributes to knowledge in a number of ways.

First, we carry out a comparative analysis between the developed and developing countries of the OECD. Second, we check if the global financial crisis (GFC) of 2008 altered the oil price–inflation relationship. We further extend our analysis to capture asymmetries using the non-linear autoregressive distributed lag model. Lastly, we use the Campbell and Thompson (2008) forecast evaluation test to comparatively assess the predictive ability of the symmetric (restricted) and asymmetric (unrestricted) models.

Our results show that asymmetries matter in the oil price–inflation nexus. Also, the effect of the GFC of 2008 is stronger for the developed countries in the short run, and the developing countries in the long run. Lastly, accounting for asymmetries in oil price yields a better forecast for inflation in both groups.

The paper adds some interesting innovations to the oil price–inflation relationship in the OECD countries. It is the study with the widest scope for such country group under two classifications of developed and developing countries. It also inculcates the role of asymmetries, financial crisis, as well as the predictive ability of oil price on inflation.

This paper aims to assess the asymmetric effects of oil price shocks and the impact of oil price volatility on the Eurozone’s supersector returns, with a particular emphasis on the impact of the subprime crisis and the euro debt crisis (EDC) on this relationship.

Empirical data consist of daily observations of the 19 EURO STOXX supersector indices and the Brent crude oil price index for the period January 2001 to August 2015. This paper uses a non-linear multifactor market model. This model accounts for heteroscedasticity and breakpoints that are identified by the Bai and Perron (1998, 2003) tests.

The results show that supersector returns are sensitive to oil price shocks. However, in most cases, their responsiveness to oil price volatility is not significant. The relationship between oil price shocks and supersector returns changes through time and depends on the sector. Financial turbulence affects the oil-stock market nexus. In most cases, the subprime crisis has had a positive impact on the oil-stock market relationship, whereas the EDC has had an overall negative effect. Before the subprime crisis, there is an evidence of asymmetric effects for some supersectors. Meanwhile, for most sectors, the asymmetric effects disappear after 2008.

The study improves understanding of the interaction between oil price risk and the Eurozone sector indices returns. Furthermore, it enables global investors to manage the risk inherent to the portfolio managers’ positions.