9.5 Development Trend of LED Encapsulation Form
201
package [33]. Among them, the lead-type electronic package is a commonly used 3–
5 mm electronic package structure, which is commonly used for indicator. The LED
packages usually have low current (20–30 mA) and low power (less than 0.1 W).
The disadvantage of this type of package is that it has a large thermal resistance
(generally higher than 100 K/W) and short lifetime. Surface mount technology is
an electronic packaging technology that can directly attach and solder electronically
packaged devices to designated position of PCB. One of its main development trends
is currently applied to wafer level LED packages. COB is the abbreviation of Chipon-Board. It is an electronic packaging technology that directly bonds LED chips
onto PCB through adhesive or solder, and then electrically interconnects the chips
and PCB boards through wire bonding. In contrast with SMT, COB greatly increases
the power density of the electronic package while reducing the thermal resistance of
the electronic package. SiP (System in Package) is a new type of electronic package
integration method. It is developed on the basis of system on chip (SOC) in order
to meet the requirements of portable development and system miniaturization. SiPLEDs can be used to assemble multiple light-emitting chips in an electronic package.
They can also be integrated with other functional devices (such as power supplies,
control circuits, optical microstructures, sensors, etc.) for building a more complex
system.
References
1. L. Zhang, Y. Zhu, W. Wang et al., Study on Ag-plated Cu lead frame and its effect to LED
performance under thermal aging. IEEE Trans. Device Mater. Reliab. 14, 1022 (2014)
2. L. Zhang, Y. Zhu, H. Chen et al., Failure analysis on reflector blackening between lead frame
electrodes in LEDs under WHTOL test. Microelectron. Reliab. 55, 799–806 (2015)
3. J.W. Park, Y.B. Yoon, S.H. Shin et al., Joint structure in high brightness light emitting diode
(HB LED) packages. Mater. Sci. Eng. A 441(1), 357 (2006)
4. F.P. McCluskey, M. Dash, Z. Wang et al., Reliability of high temperature solder alternatives.
Microelectron. Reliab. 46, 1910 (2006)
5. C. Chen, C.M. Chen, R.H. Horng et al., Thermal management and interfacial properties in
high-power GaN-based light-emitting diodes employing diamond-added SAC305 solder as a
die-attach material. J. Electron. Mater. 39(12), 2618–2626 (2010)
6. Y. Tseng, F. Hung, T. Lui, Microstructure, tensile and electrical properties of gold-coated silver
bonding wire. Microelectron. Reliab. 55, 608 (2015)
7. D. Barton, M. Osinski, P. Perlin et al., Life tests and failure mechanisms of GaN/AlGaN/ InGaN
light emitting diodes, in Proceedings of 35th Annual IEEE International Reliability Physics
Symposium, 8–10 Apr, 1997 (Denver, 1997)
8. E.F. Schubert, Light Emitting Diodes, 2nd edn. (Cambridge University Press, 2006)
9. M. Li, J. Zhang, X. Hu et al., Appl. Phys. A Mater. Sci. Process. 119(2), 415 (2015)
10. M. Jeong, S. Jeon, S. Lee et al., Effective heat dissipation and geometric optimization in an
LED module with aluminum nitride (AlN) insulation plate. Appl. Thermal Eng. 76, 212 (2015)
11. K. Zhang, G.W. Xiao, C. Wong et al., Study on thermal interface material with carbon nanotubes
and carbon black in high-brightness led packaging with flip-chip technology, in Proceedings
of 55th Electronic Components and Technology Conference, May 31–Jun 4, 2005 (Lake Buena
Vista, 2005).
12. Z. Yan, D.L. Nika, A. Balandin, Thermal properties of graphene and few-layer graphene:
applications in electronics. IET Circuits Devices Syst. 9(1), 4–12 (2015)
201
package [33]. Among them, the lead-type electronic package is a commonly used 3–
5 mm electronic package structure, which is commonly used for indicator. The LED
packages usually have low current (20–30 mA) and low power (less than 0.1 W).
The disadvantage of this type of package is that it has a large thermal resistance
(generally higher than 100 K/W) and short lifetime. Surface mount technology is
an electronic packaging technology that can directly attach and solder electronically
packaged devices to designated position of PCB. One of its main development trends
is currently applied to wafer level LED packages. COB is the abbreviation of Chipon-Board. It is an electronic packaging technology that directly bonds LED chips
onto PCB through adhesive or solder, and then electrically interconnects the chips
and PCB boards through wire bonding. In contrast with SMT, COB greatly increases
the power density of the electronic package while reducing the thermal resistance of
the electronic package. SiP (System in Package) is a new type of electronic package
integration method. It is developed on the basis of system on chip (SOC) in order
to meet the requirements of portable development and system miniaturization. SiPLEDs can be used to assemble multiple light-emitting chips in an electronic package.
They can also be integrated with other functional devices (such as power supplies,
control circuits, optical microstructures, sensors, etc.) for building a more complex
system.
References
1. L. Zhang, Y. Zhu, W. Wang et al., Study on Ag-plated Cu lead frame and its effect to LED
performance under thermal aging. IEEE Trans. Device Mater. Reliab. 14, 1022 (2014)
2. L. Zhang, Y. Zhu, H. Chen et al., Failure analysis on reflector blackening between lead frame
electrodes in LEDs under WHTOL test. Microelectron. Reliab. 55, 799–806 (2015)
3. J.W. Park, Y.B. Yoon, S.H. Shin et al., Joint structure in high brightness light emitting diode
(HB LED) packages. Mater. Sci. Eng. A 441(1), 357 (2006)
4. F.P. McCluskey, M. Dash, Z. Wang et al., Reliability of high temperature solder alternatives.
Microelectron. Reliab. 46, 1910 (2006)
5. C. Chen, C.M. Chen, R.H. Horng et al., Thermal management and interfacial properties in
high-power GaN-based light-emitting diodes employing diamond-added SAC305 solder as a
die-attach material. J. Electron. Mater. 39(12), 2618–2626 (2010)
6. Y. Tseng, F. Hung, T. Lui, Microstructure, tensile and electrical properties of gold-coated silver
bonding wire. Microelectron. Reliab. 55, 608 (2015)
7. D. Barton, M. Osinski, P. Perlin et al., Life tests and failure mechanisms of GaN/AlGaN/ InGaN
light emitting diodes, in Proceedings of 35th Annual IEEE International Reliability Physics
Symposium, 8–10 Apr, 1997 (Denver, 1997)
8. E.F. Schubert, Light Emitting Diodes, 2nd edn. (Cambridge University Press, 2006)
9. M. Li, J. Zhang, X. Hu et al., Appl. Phys. A Mater. Sci. Process. 119(2), 415 (2015)
10. M. Jeong, S. Jeon, S. Lee et al., Effective heat dissipation and geometric optimization in an
LED module with aluminum nitride (AlN) insulation plate. Appl. Thermal Eng. 76, 212 (2015)
11. K. Zhang, G.W. Xiao, C. Wong et al., Study on thermal interface material with carbon nanotubes
and carbon black in high-brightness led packaging with flip-chip technology, in Proceedings
of 55th Electronic Components and Technology Conference, May 31–Jun 4, 2005 (Lake Buena
Vista, 2005).
12. Z. Yan, D.L. Nika, A. Balandin, Thermal properties of graphene and few-layer graphene:
applications in electronics. IET Circuits Devices Syst. 9(1), 4–12 (2015)