LG Innotek of Seoul, Korea reported that the company developed an ‘advanced flip chip LED package’ that attains high efficiency and high luminous flux without deteriorating performance even after it goes through a 300℃ soldering process. The company explained that it utilized state-of-the-art semiconductor technology to create the flip chip LED package with dramatically improved reliability. As a result of these advances, LG Innotek says that commercialization of high efficiency and high luminous flux lighting products at both medium and high power became possible.
The company points out that the flip chip LED configuration has garnered the attention of the BLU (Back Light Unit) makers for about three years to serve as a high-powered LED backlight source for displays. According to the company, this attention is because the chip’s electrode directly attaches to the top surface of the PCB substrate without a connection wire, preventing wire disconnection and ensuring excellent heat dissipation.
Notably, such flip chip LED packages were commercialized only as high power LED light sources in the form of CSP (Chip Scale Package) in which reflective white resin is omitted, and the process is relatively simple. However, LG Innotek says that existing packages distributed in the market have a significant problem.
In such packages, when exposed to high temperature, the bonding between the chip and the substrate melts to dislocate the chip and reduces the brightness by about 10%. Some of the processes for fabricating lighting modules and finished products reach 250℃ or more. Therefore, producing flip chips that withstand such temperatures without melting the bonding has been difficult, the company noted.
LG Innotek says that its new 220 lumens per watt (LPW) LED package features bonding between the chip and the substrate that does not melt even at the high temperatures of 250 to 300℃. According to a representative from the company, lighting companies can use this flip-chip LED package to produce premium bulbs, tubes, and flat-panel lightings without sacrificing the light quality.
LG Innotek reportedly improved the internal structure of the package, designed its own production process, and enhanced the existing flip chip mounting technology. LG Innotek says that the newly designed internal structure employs the company’s proprietary technology for maximum efficacy and heat dissipation. Also, the company conducted a reliability test of more than 6,000 hours. The flip chip LED package achieved stable performance even when applied to the high-temperature thermal shock.
Development of the New Product Took Two Years
With the company’s strict quality verification process, it took them two years to develop the product, which is substantially longer than the period needed to develop general LED packages.
LG Innotek says it has taken thorough measures to secure its proprietary core technologies and to help its customers focus on manufacturing and sales of the modules and finished products without worrying about patent disputes related to the light source.
Its primary product family consists of high-efficiency middle-power, models for each color temperature, such as the 220 LPW class 5630 3V products and 215 LPW class 3030 3V products. In particular, LG Innotek has achieved 6V, 9V, and 12V flip chip LED packages in series of two and also for two in parallel in the 3030 product family.
A company official commented, “This high-quality flip-chip LED package is an innovative product that can advance the reliability of premium lightings to the new level.” He also added, “We expect that its application range will be greatly expanded as the product replaces the existing LED packages.”