Gallium nitride is on the "trend", and the entire industry is making a "tackling" plan

According to Jiwei.com news, in March, the "Outline of the 14th Five-Year Plan for National Economic and Social Development of the People's Republic of China and the Long-Term Goals for 2035" (hereinafter referred to as the "Outline") was announced to the public. In the field of "integrated circuits", special mention was made of the development of wide bandgap semiconductors such as silicon carbide and gallium nitride.

Why are silicon carbide and gallium nitride so important?

The reason why third-generation semiconductors are given so much attention is, on the one hand, closely related to their wide range of applications.

According to the "Top Ten Technology Trends in 2021" released by DAMO Academy, the first major trend predicted is "the third-generation semiconductors represented by gallium nitride and silicon carbide are experiencing a huge application explosion". DAMO Academy pointed out that in recent years, the cost-effectiveness of third-generation semiconductors has gradually emerged and is opening up the application market: SiC components have been used as automotive inverters, and GaN fast chargers have also been launched in large quantities. In the next five years, electronic devices based on third-generation semiconductor materials will be widely used in 5G base stations, new energy vehicles, ultra-high voltage, data centers and other scenarios.

Huaan Securities pointed out that since the third-generation semiconductor materials are more excellent and the gap with foreign countries is relatively small, the country hopes to elevate the third-generation semiconductors to a strategic level through the "14th Five-Year Plan". The third-generation semiconductors may become an opportunity for my country's semiconductor industry to overtake others. Guosen Securities also pointed out that the third-generation semiconductors are an opportunity for China's semiconductor industry to lead the world.

On the other hand, because the research work on SiC and GaN materials and devices started relatively late in China and the level is lower than that of foreign countries, the important factor hindering the progress of domestic third-generation semiconductor research is the problem of original innovation. This time, "the development of wide-bandgap semiconductors such as silicon carbide and gallium nitride" appears in the "Strengthening original and leading scientific and technological research" section of the "Planning Outline".

What other aspects of GaN need to be tackled?

As early as the 1960s, gallium nitride has been used in LED products. In recent years, as the technology has gradually matured, the application scope of gallium nitride has begun to expand to fields such as radio frequency and power. From the perspective of specific downstream applications, gallium nitride devices are currently used in 5G communication base station radio frequency transceiver units, consumer electronics fast chargers, electric vehicle chargers OBC, etc.

In terms of RF devices, since the heat dissipation and power characteristics of gallium nitride (GaN) materials can better meet the requirements of 5G base stations, and as the cost of GaN devices decreases and the process matures, gallium nitride (GaN) materials are expected to become the mainstream material for base station PAs.

In terms of power devices, fast charging has become its biggest driving force. When applied to the charger field, fast charging, small size, and high power are its most obvious features. GaN chargers solve the pain points of traditional PD chargers, such as high heat generation and poor heat dissipation.

Judging from the current development situation, GaN technology is relatively mature and prices have also fallen; GaN chargers have been favored by many consumers for their unique advantages, and the realization trajectory of the fast charging market is becoming more and more obvious.

It is understood that Navitas GaN Fast gallium nitride power chips have been widely adopted by first-tier brand customers such as Lenovo, Dell, OPPO, Xiaomi, etc., and are used in the design of fast charging chargers up to 200W. The shipment volume has exceeded 13 million and successfully achieved zero failures. This also reflects that the global mobile consumer electronics market is accelerating the adoption of gallium nitride chips to achieve fast charging of mobile devices and related equipment.

From the perspective of the industrial chain, according to the Yole report, the gallium nitride industry chain basically includes substrates, epitaxial wafers, device manufacturing and other links. Currently, mainstream gallium nitride manufacturers are still concentrated in European countries and Japan, and Chinese companies have not yet entered the first echelon on the supply side.

Although relatively backward, a relatively complete industrial chain system has been formed in China. In the field of gallium nitride, the companies engaged in the growth of gallium nitride single crystals mainly include Suzhou Navitas, Dongguan Zhonggai, Shanghai Gatech and Xinyuanji; the domestic manufacturers engaged in gallium nitride epitaxial wafers mainly include Sanan Optoelectronics, Saiwei Electronics, Hailu Heavy Industry, etc.; the manufacturers engaged in gallium nitride devices mainly include Sanan Optoelectronics, Wingtech Technology, Saiwei Electronics, Jucan Optoelectronics, Qianzhao Optoelectronics, etc.

Gallium nitride has significantly improved performance, efficiency, energy consumption, size, etc. compared to mainstream silicon power devices on the market, but its development also faces many problems.

Shortage of raw materials. Gallium nitride is a substance that does not exist in nature and must be completely synthesized artificially. Gallium nitride does not exist in liquid form, so it cannot be pulled out using the Czochralski method of single crystal silicon production technology. It is synthesized purely by gas reaction. Due to the long reaction time, slow speed, many reaction by-products, demanding equipment requirements, extremely complex technology, and extremely low production capacity, gallium nitride single crystal materials are extremely rare.

In addition, my country currently lacks the preparation of SiC wafers, and most equipment is imported from abroad. Mainstream GaN device companies all use silicon carbide substrates, because GaN devices based on silicon carbide substrates have better performance and higher yield than GaN devices based on silicon substrates, which can better reflect the advantages of GaN materials, but the cost of silicon carbide substrates is higher.

The packaging cost of GaN is extremely high. GaN is mainly packaged in metal ceramics, and the packaging cost accounts for one-third to one-half of the total device cost. Although the industry has been trying to replace metal ceramic packaging with pure copper, plastic packaging, and cavity plastic packaging, metal ceramic packaging is still the preferred packaging for GaN devices due to its advantages in performance, heat dissipation, and reliability.

It is reported that in the field of 5G radio frequency, the technical barriers of radio frequency are much higher than those of power electronics. Power electronics technology mainly involves materials, device design, front-end process and back-end packaging and testing. However, radio frequency devices have an additional technical dimension of electromagnetic waves, involving radio frequency circuits, radio frequency power amplifiers and microwave electronics, and have a higher technical threshold.

How the dual drive of "policy + capital" can help the industry overcome difficulties

New energy and 5G communications are driving the rise of third-generation semiconductors. With the support of national policies and the leadership of industry giants, the prospects for the third-generation semiconductor industry represented by GaN and SiC are optimistic.

According to TrendForce, as the epidemic situation eases, the demand for 5G base station RF front-end, mobile phone chargers and automotive energy will gradually increase. It is expected that the revenue of GaN communication and power devices in 2021 will be US$680 million and US$61 million respectively, a year-on-year increase of 30.8% and 90.6%. The revenue of SiC device power field can reach US$680 million, a year-on-year increase of 32%.

The Shanghai Lingang New Area has released a special plan for the integrated circuit industry (2021-2025). The plan proposes to promote the construction of 6-inch and 8-inch GaAs, GaN and SiC process lines, and accelerate the verification and application of compound semiconductor products for application scenarios such as 5G and new energy vehicles.

Recently, six departments including the Ministry of Science and Technology, the National Development and Reform Commission, and the Ministry of Industry and Information Technology issued the "Plan for the Construction of the G60 Science and Technology Innovation Corridor in the Yangtze River Delta" (hereinafter referred to as the "Plan"). The "Plan" clearly states that a number of leading enterprises with international competitiveness will be cultivated in key areas, and a number of future industries such as quantum information, brain-like chips, and third-generation semiconductors will be accelerated.

In addition to policy support, domestic companies also need to make further breakthroughs in technology and preparation equipment, and accelerate their layout in mass supply.

On February 26, Hitech High-Tech stated on the investor interaction platform that the company has made breakthroughs in the RF gallium nitride foundry process technology for 5G macro base stations, and can already achieve foundry manufacturing in the wafer process.

On March 18, China Electronics Technology Group Corporation learned that at the China International Semiconductor Equipment and Materials Exhibition, the group's Electronics Equipment successfully released vertical LPCVD (low-pressure chemical vapor deposition) equipment. As a key manufacturing equipment for third-generation semiconductors, it will provide a solid guarantee for my country to quickly catch up with the international advanced level in the field of third-generation semiconductors.