Diamond wafers have broad development prospects

In May 2025, Fuji Economy conducted a survey on the global power semiconductor wafer market and released a forecast up to 2035. Among them, the silicon carbide (SiC) wafer market is particularly noteworthy, with its size expected to expand from 143.6 billion yen in 2024 to 619.5 billion yen in 2035, an increase of about 4.3 times.

 

The latest survey covers eight types of power semiconductor products, including silicon chips, SiC bare chips, SiC epitaxial chips, gallium nitride (GaN) chips, gallium oxide chips, diamond chips, aluminum nitride chips, and germanium dioxide chips. The survey will take place from February to March 2025.

 

The focus this time is on the SiC chip market. In 2024, the slowdown in demand for SiC power semiconductors has had an impact. In this environment, sales have increased, mainly targeting Chinese wafer manufacturers, with a year-on-year increase of 81.9% in sales by quantity (area). However, due to the increase in cheap products, the price of 6-inch wafers has decreased. In terms of value, it only increased by 46.1% compared to the previous year.

 

We expect sales volume and revenue to increase by approximately 20% year-on-year in 2025. The reason is that power semiconductor manufacturers have postponed capital investment in SiC power semiconductor 8-inch production lines. The 8-inch wafer market is expected to expand in the future, but due to the decline in unit prices, it is believed that the growth rate of the amount will not be as high as the growth rate of sales.

 

From the perspective of SiC wafer market size, 6-inch wafers account for over 90% of sales and will continue to be the mainstream in the future. Although some regions such as China are still selling 4-inch wafers, demand is declining. On the other hand, countries such as China have started selling 8-inch wafers to the outside world, and it is predicted that demand will increase significantly after 2026.

 

The diamond wafer market size is expected to reach 4.6 billion yen by 2035

Another market worth paying attention to is next-generation semiconductor wafers such as diamond wafers, aluminum nitride wafers, and germanium dioxide wafers. The diamond wafer market is expected to take off from 2026. Especially the commercialization of 2-inch wafers is expected to accelerate the development of the diamond power semiconductor market, which is expected to reach a market size of 4.6 billion yen by 2035.

 

The 4-inch aluminum nitride wafer samples have started shipping. The application scope is constantly expanding, and it is expected that this technology will achieve full mass production in the future. The germanium dioxide chip is planned to be developed as a 6-inch epitaxial wafer and is expected to start sales around 2030.

 

In terms of silicon wafers, the market will shrink in 2024 along with the silicon power semiconductor market. It is expected to steadily increase from 2025 onwards. It is expected that with the practical use of 6-inch wafers, the market for GaN single crystal wafers and gallium oxide wafers will expand.