Abstract
Novel continuous and mass customizable light-emitting diode (LED) lighting foil system, capable to produce adequate lighting levels for general lighting, was designed, processed, and characterized. Lighting element substrate was processed by roll-to-roll (R2R) printing using silver ink and automatic bonding of LEDs and current regulators on polyethylene terephthalate (PET) substrate using isotropic conductive adhesive (ICA). Demonstrator consisting of two basic lighting elements contained 98 LEDs and produced 860 lm when running with 25 mA operational current through the LEDs when using total electrical driving power of 8.4 W. Measured power conversion efficiency of the demonstrator was 31 % and efficacy 102 lm/W. Element produced 460 lx illumination level measured by an illumination level meter at element’s central axis at distance of 1 m. At a distance of 2 m, illumination level was 110 lx, respectively. Temperature measurements with T3Ster thermal characterization instrument showed that when driving LED with maximum nominal driving current of 100 mA, LED junction temperature was about 120 °C, when lighting element was in air in room temperature. Accelerated environmental stress tests consisting of 500 cycles from −40 … +80 °C in aging oven and 1000 h in +60 °C/95 % RH climate chamber were performed to test samples without any failures. In addition, over 700 bending cycles using 20 mm bending radius were performed to test samples without any failures, so bonding of LEDs were shown reliable according to these tests. Achieved results proved that thin, flexible, and large area high luminous flux lighting elements and systems can be processed based on plastic foil manufactured using R2R silver ink printing and R2R automatic bonding of LEDs and regulator components using ICA on that foil.
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References
D’Andrade B, Forrest S (2004) White organic light emitting devices for solid state lighting”. Adv Mater 16:18
Blom P, van Mol T (2011) LEDs roll. PhysWorld 2011:32–35
van den Brand J et al (2008) Systems-in-foil—devices, fabrication processes and reliability issues. Microelectron Reliab 48:8–9
(2011) White Paper: OE-A Roadmap for Organic and Printed Electronics
Kim H, et al (2011) Unusual strategies for using indium gallium nitride grown on silicon (111) for solid-state lighting. Proc Natl Acad Sci USA 108
Kim Y et al (2012) Optimization of flexible substrate for COF (chip on flexible) LED packaging. Proc. 59th Electronic Components and Technology Conf, San Diego, pp 1953–60, May 2012
Park S et al (2009) Printed assemblies of inorganic light-emitting diodes for deformable and semitransparent displays. Science 325:5943
Keränen K et al (2012) Hot laminated multilayer polymer illumination structure based on embedded LED chips. IEEE Trans Compon Packag Technol 2:12
Wenzl F et al (2014) Foil based optical elements for beam shaping and color homogenization of phosphor converted white LED sources. Proc SPIE 9190:91900A1–7
Mukish P (2011) LED cost and technology trends: how to enable massive adoption in general lighting. LED Forum, Lyon, 2011;December 7th
Fjelstad J (2011) Flexible circuit technology. 4th ed. Seaside: BR Publishing Inc.; p. 146–147
MacDonald W et al (2007) Latest advances in substrates for flexible electronics. J Soc Inf Display 15:12
van den Brand J et al (2011) Flipchip bonding of thin Si dies onto PET foils: possibilities and applications. Proc. 18th european microelectronics and packaging conf, Brighton, September 2011. art. 6142415
Fjelstad J (2011) Flexible circuit technology. 4th ed. Seaside: BR Publishing Inc., p. 149
van den Brand J, et al (2010) A. Flip chip bonding of ultrathin Si dies onto PEN/PET substrates with low cost circuitry. In: 3rd Electronic system-integration technology conference (ESTC), IEEE, p. 1-6
Chang M et al (2012) Reliability of high-power LED packaging and assembly. Microelectron Reliab 52:5
Li Y, Wong C (2006) Recent advances of conductive adhesives as a lead-free alternative in electronic packaging: materials, processing, reliability and applications. Mater Sci Eng 51:1–3
van den Ende D et al (2013) Large area flexible lighting foils using distributed bare LED dies on polyester substrates”. Microelectron Reliab 53:12
Tapaninen O, et al (2014) Thermal management in flexible substrates for LEDs. IMAPS Nord Conf p. 1-6
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Manuscript was submitted at 24th of November 2014 for review. This work was supported in part by Painettavan Paalutus 2013 project, which was mainly funded by TEKES—the Finnish Funding Agency for Technology and Innovation.
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Keränen, K., Korhonen, P., Rekilä, J. et al. Roll-to-roll printed and assembled large area LED lighting element. Int J Adv Manuf Technol 81, 529–536 (2015). https://doi.org/10.1007/s00170-015-7244-6
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DOI: https://doi.org/10.1007/s00170-015-7244-6