Solar cells integration in over-molded printed electronics

The continuous drive to have smart flexible systems in different application areas as automotive, households, and consumer electronics utilize the development of different integration approaches to include many electronic functionalities in 3D structures. This article reports a new conceptual idea that may be used as a platform for the integration of photovoltaic (PV) cells in plastic products. By using over-molding techniques, a thin flexible power source can be produced using amorphous silicon photovoltaic modules integrated into a thermoplastic material. Moreover, a clear benefit is achieved from such a combination of solar cells applied on flexible printed foils and the use of injection molding manufacturing process. The advantages include: being lightweight, flexibility as well as cost-effectiveness. The fabrication process is explained on both single and a matrix of PV modules. Different materials used for adhesion between the cells and the printed foils are discussed in this article. Each integrated sample consisted of a flexible substrate with a PV module assembled and fixed as an insert in the mold of the injection molding machine. A polymer is over-molded on it and a plastic part is formed. Afterwards, the solar cells are tested using IV measurements to confirm the feasibility of the technology to act as a thin light power source for different applications

Arbitrarily shaped rigid and smart objects using stretchable interconnections

In this paper, we present the developments of a new technology to realize 2.5-/3-D electronic circuits. The starting point is an electronic circuit embedded in a hard thermoplastic material, which is transformed into a 2.5-/3-D shape using a thermoforming process. The electronic circuit consists of stretchable copper interconnections in combination with electronic components. The circuit is produced using conventional printed circuit board process steps: a copper sheet is laminated on a thermoplastic material, such as Polycarbonate (PC) or Polyethylene Terephthalate Glycol (PET-G). The copper is structured using lithography and wet etching, and the electronic components are assembled using conductive adhesives. We investigated the use of different designs for stretchable interconnects to overcome the stretching of the electronic circuit by thermoforming it. A semispherical-shaped mold was used for this purpose where the local strain of the substrate can reach 100% with a sharp bending. It was shown that meander-shaped interconnects could accommodate the gradual deformation during the forming of the substrate either for PC and PET-G. However, at the mold's edge, the copper-meandered tracks showed a delamination of the copper from the substrate. In the meanwhile, the electrical conductivity of the copper tracks did not show any significant variation. Another meander design based on an elliptical shape (in order to increase the length of the track) is proposed and compared with the first design

Arbitrarily shaped 2.5D circuits using stretchable interconnections and embedding in thermoplastic polymers

AbstractThis contribution describes considerations and very preliminary results in the technology development of thermoplastically deformable electronics and sensor circuits, with the intention to eventually achieve the low-cost fabrication of 2.5D free-form rigid smart objects. The technology is based on the one for elastic circuits, developed and characterized before, which is using soft elastic polymers as materials for the circuit carrier. For 1-time deformable circuits the elastic carrier needs to be substituted by a thermoplastic material. An additional step of thermoforming is necessary after the entire circuit is fabricated on a flat surface, which is the normal industrial practice for circuit fabrication and which thus is also pursued here. First tests have been executed and simple circuits fabricated, using meandered Cu tracks as 1-time stretchable interconnects, PET-G as the thermoplastic carrier and SMD LEDs and zero-ohm resistors as circuit components

The Tunisian experience of participatory health governance: the Societal Dialogue for Health (a qualitative study)

Abstract Background Tunisia has been engaged in the Societal Dialogue (SD) for Health process since 2012, a participatory health governance process aimed at bringing in people’s voice into health policy-making. Its first success was the recently released National Health Policy 2030. This paper aims to document the SD process and to bring out the lessons learned to inspire other countries. Methods This study was based essentially on a qualitative analysis of semi-structured interviews with citizen jury members and health experts that took place from May to September 2018. The qualitative analysis adopted an inductive-deductive approach according to a cross-matrix between the themes of the interview of the two groups of interviewees. Results The qualitative analysis of the data highlighted that the Societal Dialogue created a health democracy dynamic with inclusive dialogue spaces for the population, communities, and civil society to participate in health system design. It constituted a multi-actor and multidisciplinary coordination platform to increase consensus building among actors. Initial government support and high levels of volunteer commitment allowed the process to achieve a certain level of sustainability. However, this process faced and still faces many challenges such as overreliance on volunteers; a crisis of trust; political instability and the lack of an effective communication strategy. These challenges negatively influence the policy uptake of recommendations made by the Societal Dialogue for Health. Conclusion The Tunisian societal dialogue experience highlights both the successes and challenges of a structured participatory platform, as well as the effort and perseverance it takes to keep such a process functional and relevant. A key lesson from this study is that this model of participatory health governance eventually reaches a stage where population, community, and civil society participation needs to be more institutionalized within the government routine so that it can credibly feed into health policy review processes and inform decision-makers on a regular basis