4
1 Introduction
source devices the light source failure caused by package is much larger than chip
itself [18]. Packaging process is an important part of LED production. Appropriate
packaging can protect the LED chip from damage, improve its mechanical performance and life,strengthen heat dissipation, reduce the junction temperature of the
LED chip, improve the photoelectric and thermal performance of the LED,optimize
the optical design, and improve the luminous efficiency of the LED. Imperfect packaging can lead to serious light loss, low luminous efficiency, uneven light color,
short service life and many other problems of LED devices. From the perspective of
packaging technology, LED packaging has gone through the development stages of
pin-type (Lamp LED), surface-mounted (SMT LED), on-board chip direct-mounted
(COB), system-mounted (SiP) and so on. It is now developing chip-scale wafer-level
packaging, IC packaging and other forms. Regardless of the packaging technology,
we must take into account the effects of thermal management, packaging materials, optical design, electrostatic protection and other factors on the photoelectric
performance, luminous efficiency and lifetime of LED [19].
In 2014, the Nobel Prize Committee stated: “Incandescent lamps will light up the
twentieth century, and LED lights will light up the twenty-first century.” In the past
20 years, the technology of group III nitride LED has been widely used not only
in lighting, backlight, display and other fields, but also in the progress of modern
lighting technology. It has gradually changed people’s way of life. It has been developing in the fields of biology, agriculture, medical treatment, health care, aviation,
aerospace and communication. Nitride LED has played an important role in social
progress and economic prosperity [20]. However, with the continuous expansion of
LED applications and the emergence of new applications, many new basic scientific
problems intersecting with communication, control, sensing, information processing,
electronics, software, optics and other fields will emerge. Such new scientific issues
need to be solved urgently.
Research on the technology of group III nitride light emitting diodes in China
began in the late 1990s. Especially since the launch of “Semiconductor Lighting
Project” in 2003, we have carried out a series of basic, prospective and strategic scientific and technological research. The most noticeable achievements are the manufacturing of MOCV equipment, the growth of epitaxy materials, chip manufacturing
process and packaging integration technology. We have done original works which
have been recognized internationally. The luminous efficiency of white LED developed by us has increased from 20 lumens/W in 2004 to 160 lumens/W in 2014 at
350 mA working current. The development of LED has also made tremendous contributions to energy saving, emission reduction and economic construction in China.
With the deepening of basic research and engineering application, the technology of
group III nitride light emitting diodes will further promote the development of the
third-generation semiconductor technology and industry in China.
1 Introduction
source devices the light source failure caused by package is much larger than chip
itself [18]. Packaging process is an important part of LED production. Appropriate
packaging can protect the LED chip from damage, improve its mechanical performance and life,strengthen heat dissipation, reduce the junction temperature of the
LED chip, improve the photoelectric and thermal performance of the LED,optimize
the optical design, and improve the luminous efficiency of the LED. Imperfect packaging can lead to serious light loss, low luminous efficiency, uneven light color,
short service life and many other problems of LED devices. From the perspective of
packaging technology, LED packaging has gone through the development stages of
pin-type (Lamp LED), surface-mounted (SMT LED), on-board chip direct-mounted
(COB), system-mounted (SiP) and so on. It is now developing chip-scale wafer-level
packaging, IC packaging and other forms. Regardless of the packaging technology,
we must take into account the effects of thermal management, packaging materials, optical design, electrostatic protection and other factors on the photoelectric
performance, luminous efficiency and lifetime of LED [19].
In 2014, the Nobel Prize Committee stated: “Incandescent lamps will light up the
twentieth century, and LED lights will light up the twenty-first century.” In the past
20 years, the technology of group III nitride LED has been widely used not only
in lighting, backlight, display and other fields, but also in the progress of modern
lighting technology. It has gradually changed people’s way of life. It has been developing in the fields of biology, agriculture, medical treatment, health care, aviation,
aerospace and communication. Nitride LED has played an important role in social
progress and economic prosperity [20]. However, with the continuous expansion of
LED applications and the emergence of new applications, many new basic scientific
problems intersecting with communication, control, sensing, information processing,
electronics, software, optics and other fields will emerge. Such new scientific issues
need to be solved urgently.
Research on the technology of group III nitride light emitting diodes in China
began in the late 1990s. Especially since the launch of “Semiconductor Lighting
Project” in 2003, we have carried out a series of basic, prospective and strategic scientific and technological research. The most noticeable achievements are the manufacturing of MOCV equipment, the growth of epitaxy materials, chip manufacturing
process and packaging integration technology. We have done original works which
have been recognized internationally. The luminous efficiency of white LED developed by us has increased from 20 lumens/W in 2004 to 160 lumens/W in 2014 at
350 mA working current. The development of LED has also made tremendous contributions to energy saving, emission reduction and economic construction in China.
With the deepening of basic research and engineering application, the technology of
group III nitride light emitting diodes will further promote the development of the
third-generation semiconductor technology and industry in China.