LED substrate sapphire is king

The LED substrate material is the basic material of the semiconductor lighting industry, which determines the development route of semiconductor lighting technology. At present, materials that can be used as LED substrates include Al2O3, SiC, Si, GaN, GaAs, Zno, etc., but the most widely used ones are Al2O3, SiC, and Si, thus forming three different technical routes. From the current development of the LED substrate industry, the sapphire substrate is still the mainstream of the LED substrate. The silicon substrate is cost-effective and is expected to lead the market. At the same time, under the steadily growing market of LED downstream applications, the upstream LED substrate Material demand will continue to grow.

The sapphire substrate is still the mainstream of the LED substrate, and the market share is over 95%. Sapphire is the most important substrate for LED chips on the market, accounting for more than 95% of the market share of LED chips. Most of the major LED manufacturers in the industry use sapphire substrates. The main representatives are Nichia, OSRAM Opto, Lumileds, Seoul Semi, Epistar and Sanan Optoelectronics. The cost of silicon carbide substrates is high, and the representative manufacturer is Cree, Inc. Monopoly, almost no other manufacturers involved; silicon substrate technology started late, the industry scale is relatively small, the market share is not high, the main representative manufacturers using silicon substrates are Jingneng Optoelectronics and Samsung.

The comprehensive cost performance of silicon substrates is obvious, and it is expected to lead the development trend. Although the current mainstream uses sapphire or silicon carbide substrates for epitaxial growth, both of them are expensive and monopolized by large foreign companies. The advantage of a silicon substrate is that it is less expensive than sapphire and silicon carbide substrates, enabling the fabrication of larger sized substrates, increasing the utilization of MOCVD and thereby increasing die yield. For China, where the price of LED chips is extremely serious, the low cost and low price of silicon substrates are undoubtedly very advantageous.

In addition, since the silicon substrate LED is single-sided light, it is especially suitable for lighting such as automobile lighting, searchlights, miner's lamps, mobile lighting, and the like. Although there are still technical problems to be solved in the current silicon substrate LED, such as large lattice mismatch between the silicon substrate and the GaN material, the dislocation density inside the GaN is high and the internal quantum efficiency of the LED is affected, but the silicon substrate It provides a feasible technical route for domestic manufacturers outside the sapphire and silicon carbide substrates. It is the only opportunity that can break through the foreign patent blockade and is expected to lead the market in the future.

The downstream application market has grown steadily, injecting momentum into the upstream substrate materials. In the future, benefiting from the continued support of national policies and the awareness of citizens’ energy conservation and environmental protection, the global LED lighting market is expected to continue to expand. According to the OFweek Industry Research Institute, the global LED lighting market will maintain a growth rate of around 8% in the next three years. By 2021, the global market is expected to exceed 740 billion RMB. At the same time, the demand for small pitch and Mini/Micro LEDs has driven the LED display market to continue to grow steadily. By 2021, the global LED display market has exceeded 50 billion RMB. The steady growth of LED downstream applications will drive the continued growth of the substrate materials market.