High-power LED cooling needs to be improved, replacing substrate technology into hot spots

In the current LED applications, applications such as LCD TV backlighting and lighting are accelerating, and the use of high-power LEDs is increasing, and related cooling technologies are becoming increasingly important. In order to pursue a better heat dissipation solution, various LED epitaxial and chip manufacturers have invested in various alternative substrate technologies, including metal substrate technologies such as copper, and ceramics, diamond coatings and other materials as substrates. Improve the heat dissipation of high power LEDs. At present, some manufacturers have started a small amount of trial production and shipment, but in general they have not reached the mass production stage.

The so-called alternative substrate technology, currently more manufacturers are investing in the development of metal substrate technology, that is, after crystal growth on the sapphire substrate, the substrate is removed, and a layer of metal is replaced to replace the underlying layer. The development of this new technology is mainly due to the high heat dissipation requirements of high-power LEDs, because the metal has better thermal conductivity and better heat dissipation. But the demand for sapphire substrates has not changed.

Ideally, the LED industry is now also investigating the use of alternative substrate technology, replacing sapphire substrates, and the ability to reuse sapphire substrates, just like recycling. That is, after extending the sapphire on the outside, the substrate can be removed, and the crystal growth can be taken back. However, the difficulty is still large, because the substrate is easily damaged after being crystallized, thereby affecting the effect of reuse.

At present, among LED epitaxial and chip manufacturers, Taiwan LED manufacturers are quite active. Jingdian and Taigu have invested in other technologies that can replace sapphire substrates, hoping to achieve better heat dissipation for high-power LEDs. At the same time, the direction of research and development is not limited to metal substrates. It is understood that the metal is hot and cold, and the two metals of different properties are prone to cracking under the hot environment.

Yuyuan has actively invested in the development of LED chips for copper-tungsten substrate technology. At this stage, it is mainly used to produce micro-projection light source LED products . It is reported that the sapphire substrate has low driving power and cannot conduct heat, and the copper-tungsten substrate can drive 6W-7W power, which is suitable for micro-projection products.

The company has cooperated with international companies to launch patents and launch high-brightness green LED chips for micro-projectors. It started small-scale trial production in May this year and will be shipped in volume from June. It is estimated that by the end of this year, the green light chip will account for 10% of the revenue of the company, and the monthly shipment will reach more than 1 million. The company expects that future copper-tungsten substrate LEDs will also have the opportunity to be applied to lighting or some backlight products.