Third-generation semiconductors are experiencing investment boom. Why are SiC substrates the key to development?

The third-generation semiconductors have become a new battleground. Major countries such as China and the United States have also introduced policies to promote their development, and domestic and foreign companies are also competing to invest.

According to Tech News, Yang Ruilin, research director of the Industrial Technology Research Institute's International Industrial Science Institute, believes that third-generation semiconductors have become a hot focus of attention for governments and industries in recent years, mainly due to three major catalysts.

First, Tesla, a major American electric car manufacturer, was the first to adopt the third-generation semiconductor silicon carbide (SiC), allowing SiC components to actually take advantage of their good heat dissipation and improve the endurance of electric vehicles.

Second, global environmental awareness is on the rise. In order to achieve carbon neutrality and net zero carbon emissions, governments have set timetables for phasing out fuel vehicles, prompting automakers to accelerate their transition to electric vehicles.

Third, in order to learn from the lesson of being controlled by others in silicon-based semiconductors, mainland China has introduced policies to strongly support the development of third-generation semiconductors.

Unlike China's approach of spending money on subsidies, Yang Ruilin said that the infrastructure plan promoted by the US government will massively build charging stations, which will create a market for SiC in the third-generation semiconductors.

Yang Ruilin further pointed out that SiC substrates are the biggest key to the development of third-generation semiconductors. SiC transistors and silicon carbide-based GaN transistors are two products with higher growth potential, with annual compound growth rates of 27% and 26% respectively, and both require the use of SiC substrates.

In addition, the cost structure of SiC power components is also dominated by substrates, which include crystal growth, cutting, and grinding, accounting for the largest proportion, up to 50%.

Yang Ruilin mentioned that the difficulty in manufacturing SiC substrates is the main reason for the high cost. Thermal field control and seed control are very critical, but they can only follow the traditional steelmaking method, learning by doing and learning by doing. Moreover, the efficiency of SiC crystal growth is 100 to 200 times slower than that of Si. Si crystal growth can produce a 200 cm high crystal rod in about 3 days, while SiC takes 7 days to grow a 2 to 5 cm crystal ball. In addition, SiC is hard and brittle, and it is difficult to cut, grind and polish, which will result in a lot of waste.

Currently, Cree is the world's leading SiC substrate manufacturer, with a market share of over 60%. Currently in my country, Shengxin Materials and Wensheng Materials, both subsidiaries of Guangyun Group, have invested in the SiC substrate field.

Yang Ruilin emphasized that SiC substrates not only account for a high proportion of the cost of power components, but are also closely related to product quality. SiC substrates will be a key to the development of SiC. Manufacturers including STMicroelectronics (ST) are actively developing upstream SiC substrates to enhance their competitiveness, which is worthy of reference for mainland and Taiwanese manufacturers.