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Fabrication and Evaluation of Heat Transfer Property of 50 Watts Rated LED Array Module Using Chip-on-board Type Ceramic-metal Hybrid Substrate

Chip-on-board 형 세라믹-메탈 하이브리드 기판을 적용한 50와트급 LED 어레이 모듈의 제조 및 방열특성 평가

  • Heo, Yu Jin (Nano Materials and Convergence Center, Korea Institute of Ceramic Engineering and Technology) ;
  • Kim, Hyo Tae (Nano Materials and Convergence Center, Korea Institute of Ceramic Engineering and Technology)
  • 허유진 (한국세라믹기술원 나노융합소재센터) ;
  • 김효태 (한국세라믹기술원 나노융합소재센터)
  • Received : 2018.12.04
  • Accepted : 2018.12.28
  • Published : 2018.12.31

Abstract

This paper describes the fabrication and heat transfer property of 50 watts rated LED array module where multiple chips are mounted on chip-on-board type ceramic-metal hybrid substrate with high heat dissipation property for high power street and anti-explosive lighting system. The high heat transfer ceramic-metal hybrid substrate was fabricated by conformal coating of thick film glass-ceramic and silver pastes to form insulation and conductor layers, using thick film screen printing method on top of the high thermal conductivity aluminum alloy heat-spreading panel, then co-fired at $515^{\circ}C$. A comparative LED array module with the same configuration using epoxy resin based FR-4 PCB with thermalvia type was also fabricated, then the thermal properties were measured with multichannel temperature sensors and thermal resistance measuring system. As a result, the thermal resistance of the ceramic-metal hybrid substrate in the $4{\times}9$ type LEDs array module exhibited about one third to the value as that of FR-4 substrate, implying that at least triple performance of heat transfer property as that of FR-4 substrate was realized.

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Fig. 1. Schematic illustration of chip-on-board (COB) type LED array module with ceramic-metal PCB: (a) single chip and (b) multichip mounted module.

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Fig. 2. Circuit diagram of 50 watts rated LED array module consisted of 36 LED chips.

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Fig. 3. Schematic illustration of LED array module with thermal-via type FR-4 PCB: (a) single chip and (b) multichip mounting module.

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Fig. 4. Optical images of fabricated 50 watts rated LED array module panels: circuit layout of 4 × 9 LEDs arrayed on ceramic-metal hybrid PCB panel (a) without top protection layer, (b) with top protection layer, and (c) comparative LED array module made with thermal-via FR-4 PCB.

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Fig. 5. Measurement of Ta in 50 watts LED array modules using multipoint temperature sensors (without thermal tape): (a) with COB type ceramic-metal PCB, (b) temperature measuring point, and (c) with thermal-via type FR-4 PCB.

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Fig. 6. (a) Thermal resistance data obtained by cumulative structure functions of 50 watts rated 4 × 9 LEDs array modules with (I) COB type ceramic-metal PCB and (II) thermal-via type FR-4 PCB and (b) equivalent thermal resistances and thermal capacitances circuit by Cauer-type RC ladder model.

Acknowledgement

Supported by : Small & Medium Business Administration (SMBA)

References

  1. Philips, "White Paper: Street Lighting", (2014), from www.philips.com.
  2. S. Liu and X. B. Luo, "LED Packaging for Lighting Applications: Design, Manufacturing and Testing", Wiley and Chemical Industry Press (2011).
  3. P. Mottier, "LEDs for Lighting Applications", Wiley (2008).
  4. H. W. Shin, H. S. Lee, J. H. Bang, S. H. Yoo, S. B. Jung, and K. D. Kim, "Variation of Thermal Resistance of LED Module Embedded by Thermal Via", J. Microelectron. Packag. Soc., 17(4), 95 (2010).
  5. M. Arik, C. Becker, S. Weaver, and J. Petroski, "Thermal Management of LEDs: Package to System", Third International Conference on Solid State Lighting, Proc. 48th SPIE. 5187, 64 (2004).
  6. M. Kang and S. Kang, "Influence of $Al_2O_3$ Additions on the Crystallization Mechanism and Properties of Diopside/anorthite Hybrid Glass-ceramics for LED Packaging Materials", J. Cryst. Growth., 326, 124 (2011). https://doi.org/10.1016/j.jcrysgro.2011.01.081
  7. J. K. Sim, K. Ashok, Y. H. Ra, H C. Im, B. J. Baek, and C. R. Lee, "Characteristic Enhancement of White LED Lamp using Low Temperature co-fired Ceramic-chip on Board Package", Curr. App. Phys., 12, 494 (2012). https://doi.org/10.1016/j.cap.2011.08.008
  8. Y. J. Heo, H. T. Kim, S. Nahm, J. H. Kim, Y. J. Yoon, and J. H. Kim, "Ceramic-metal Package for High Power LED Lighting", Frontiers of Optoelectronics, 5(2), 133 (2012). https://doi.org/10.1007/s12200-012-0252-3
  9. Y. J. Heo and H. T. Kim, "Low-temperature Co-firing of Camber-free Ceramic-metal Base LED Array Package," J. Microelectron. Packag. Soc., 23(4), 35 (2016). https://doi.org/10.6117/kmeps.2016.23.4.035
  10. H. M. Cho, H. J. Kim, C. S. Lee, K. S. Bang, and N. K. Kang, "Warpage of Co-fired High K/Low K LTCC Substrate", J. Microelectron. Packag. Soc., 11(3), 77 (2004).
  11. A. Poppe, G. Farkas, and G. Horvath, "Electrical, Thermal and Optical Characterization of Power LED Assemblies", Proc. 12th International Workshop on Thermal Investigations of ICs (THERMINIC 2006), Nice, France (2006).