WICOP LEDs without the need for packaging

WICOP is a new concept for an LED product which has overcome the limits posed by the existing CSP solutions. Seoul Semiconductor succeeded in developing and producing the product for the first time worldwide in 2012. As it is designed to directly connect the chip to PCB, there is no need for packaging processes, such as die bonding or wire bonding. In addition, as there is no intermediate substrate, the size of the chip and package is 100% the same. It is characterised by the super small size and high efficiency. It is also good for the high luminance and thermal conductivity.

In the case of the widely available product TOP LED, a variety of equipment is required for the production, such as die bonding machines to attach the chip to the lead frame, and wire bonding machines to connect electrodes to the gold wire. Due to this packaging process, a conventional LED results in a package size larger than the actual chip size, and so space is limited as the size of the chip could not be made smaller to meet specification requirements.

CSP technology, derived from silicon, is a technology developed to minimise the size of semiconductor parts to the size of a chip. Generally, when the size of the package does not exceed more than 1.2 times the chip, it is classified as CSP. This technology was applied to the LED industry and other companies announced products using this technology in 2012. However, as products using this technology need die bonding equipment, intermediate substrate or ceramic and silicon material to attach the chip to the PCB, it is difficult to see the technology as a complete CSP.