2024-01-16

CSP packaging market dilemma

Different voices come from questioning the naming of "no package" and "no package". In the market, many people call "white chip" as "pack-free chip", in fact, the LED industry has never produced chips that can be used without packaging. The main reason why non-packaging is not feasible is that the packaged line, whether it is a wire or flip-type electrical connection area, will be exposed to moisture in the air oxidation, and then fail. In order not to let the electrical connection fail, it is inevitable to wrap the chip and the welding area with a transparent material that is water and gas proof to complete the LED optical component. Since the flip chip is a co-metal welding process instead of the typical wire process, the fluorescent layer is coated with the sapphire and the side wall of the chip as the light outlet window, so it appears to eliminate most of the packaging process. In practical application, it is necessary to use transparent colloid with appropriate refractive index as the outer sealing medium, whether for optical type or for optical output. Therefore, "free packaging" never existed.

Skeptics also pointed out that CSP is still in essence in the original lm/$trajectory, nothing more than to seize the market share of other packaging, one did not expand the industry living space, two did not reduce the competitive pressure of the industry, even if the implementation of 2500lm/$, there is no value. Supporters emphasize that the earliest use of CSP is the backlight and flash, the current Apple and Samsung mobile phone flash are using CSP unpackaged chips, Samsung and LG ultra-thin TV part of the use of CSP unpackaged chips; In the lighting industry, CSP has a wide range of applications because of its small size and high flexibility.
In addition, the LED lighting industry from the ascendant to gradually mature, the discussion of standardization has never stopped. The homogenization of the original LED high-power products is serious, and CSP has gradually gained a certain degree of recognition in the market after the emergence of CSP, and the development trend is good. However, because the CSP market has not fully erupted, the product has not yet formed a standard specification.

CSP is considered by its supporters to be the future development trend of LED. First of all, from the performance point of view, it not only solves the development of miniaturization of the package volume and improves the heat dissipation problem, but also can realize the simplification and miniaturization of the package of a single device, which can greatly reduce the material cost of each device, so the capacity of mass production is very large. Secondly, from the existing development model, the development of the industry from the "chip factory + packaging factory + application business" model to the "chip factory + application business" model, eliminating the packaging link, shortening the industrial chain, will reduce the entire circulation cost, so that the LED price closer to the people. Finally, from the perspective of the previous packaging process, the high power package is based on the thinfilm wafer, and then the wafer is bonded to the ceramic substrate, and then the phosphor coating, while the low and medium power package is mostly based on the horizontal wafer, using a wire holder and requiring a wire process, or using the QFN package type, in the way of spraying phosphor. CSP technology offers new options for high power and medium power packages.

Cheng Shengpeng, general manager of stereo Optoelectronics, said that CSP has many advantages: 1, better stability, without gold wire and support, the failure rate is lower. The chance of damage during installation, transportation and storage is greatly reduced, reducing production losses. 2, smaller size, higher optical density, more conducive to light control. 3, lower thermal resistance, direct contact with the bottom of the chip plating pad, reduce the thermal resistance layer. 4, better flexibility, can be arbitrarily combined into a variety of power and series and number. 5, more cost-effective, reduce the amount of support and silica gel, reduce the circulation link of packaging, and reduce the overall cost.