White light chip (packaging) impact on the LED Market

The fluorescent powder in the LED packaging unit is directly connected with the wafer, and is independently produced as a novel product capable of directly lighting the white light".

White chip package

Perhaps we should give a more rigorous definition of white chips:

1) the phosphor layer is tightly coated with the wafer (Conformal Coating).

2) the wafer surface should be coated with a perfect five smooth surface (Pentahedral Coating).

3) the thickness of the phosphor layer should be adjusted to the optimum proportion (The Most Appropriate Phosphor Thickness) of the wafer to maximize the efficiency of the white light.

White chip products, from crystal to promote the concept of "free packaging", it has attracted market attention. Packaging as a product name, it is no provocation to the packaging industry. LED employees or have great interest, or, as in droves, sniff at or think it is venomous serpents and wild beasts, the rebirth of the operation, business development or as a stumbling block, in any case, is since 2012, the most talked about topic for the LED industry.

In the market, many people call "white chips" as "non packaged chips"; in fact, the LED industry has never produced a chip that can be used without packaging. Packaging is not feasible, the main reason is that after the packaging of the line, whether it is the line or flip type of electrical connection area, will be exposed to the air in the air oxidation, and thus failure. In order not to let the electrical connection failure, we inevitably have to use the gas barrier transparent material wrapped in the wafer and weld area, in order to complete the LED optical components.

The term "free packaging" comes from the flip chip. The flip chip adopt eutectic welding process, instead of the typical winding process of the fluorescent layer is coated on the sapphire wafer and as a side light windows on the wall, so look like most of the program can be exempted from the package. In practical application, it is necessary to use the appropriate refractive index of the transparent colloid as the external sealing medium, either for the light type or for the light output rate. So free package never existed.

The truth of the process of packaging the chip?

"Under the term free package stirred up the wafer", the hidden process is actually the truth, as the current production of mixed light coating process, it is difficult to be used for wire type chip, a fluorescent layer will be more or less applied to the electrode, resulting in subsequent welding difficulties. In the current process, even if the electrode can be avoided, the yield of the white light wafer is too low to be popular. Under the premise of manufacturing difficulties, vertical white light chip or a small number of companies can produce a small amount of white light on the surface of the chip has been unable to launch.

Up to now, most of the process of LED packaging process has become more sophisticated equipment and shape; the only difficulty is to control the proportion of the amount of phosphor in each lump of glue. In the dispensing process, the value of the error per thousand dispensing volume has shrunk from 2000 in early 7% to the current 3%, but even if only about 3% of the amount of phosphor error, but also enough to cause the naked eye color deviation. The color deviation of the naked eye can identify, in order and within 3 macadam, using the typical packaging dispensing process, the degree of precision only the color deviation is reduced to 5 order macadam. Visible color deviation, has always been the main reason for the loss of LED packaging factory inventory; especially in the United States issued a new energy star standards, universal color deviation of the LED light source requirements more stringent. This allows the packaging plant had to seek more accurate mixing process.

The appearance of white chips is a kind of redemption of packaging process. In theory, after the LED packaging factory to obtain white light chips, it is no longer necessary to mix color big brains. The color of the responsibility will be moved to the end of the wafer manufacturing, as long as the package end control of purchase, inventory or waste risk can be reduced effectively; along the way, as long as the next white wafer supply stability, packaging factory can reduce the manufacturing process of color light mixing and capital expenditure.

Overall, the emergence of white chips seems to be beneficial to the packaging industry. But from the old risk, the new risk is also followed: when the responsibility of mixed color shift to the end of the chip, the importance of the packaging plant will be reduced.

Therefore, white chips, arguably, will cause a great impact on the LED packaging industry. However, the foregoing analysis is based on the development of a "line type white light chip" can be a large number of manufacturing conditions will occur. In line type white light chip, especially in the "horizontal chip" as the bulk, at least 80% of the market share.

In the end who can break through the technical bottleneck, a large number of production level white chips, the entire LED industry innovation? Let's wait and see.

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