Diamond semiconductors: How far is industrialization?
Diamond semiconductors are one of the focuses in the new round.
On October 9, 2025, the Ministry of Commerce and the General Administration of Customs jointly issued four announcements to implement export controls on certain items, including diamond, in accordance with the Export Control Law of the People's Republic of China, the Foreign Trade Law of the People's Republic of China, the Customs Law of the People's Republic of China, and the Regulations of the People's Republic of China on Export Control of Dual - Use Items, in order to safeguard national security and interests and fulfill international obligations such as non - proliferation.
In fact, diamond has long been the focus of attention in the future semiconductor market. In 2022, the Bureau of Industry and Security (BIS) of the U.S. Department of Commerce issued a temporary final rule in the Federal Register to implement export controls on four "emerging and foundational technologies", two of which are ultra - wide bandgap semiconductor materials such as gallium oxide and diamond.
Diamond, the Semiconductor of the Future
Currently, semiconductor materials have developed to the fourth generation.
The first - generation semiconductor materials are mainly silicon and germanium; the second - generation semiconductor materials are mainly gallium arsenide (GaAs) and indium phosphide (InP); the third - generation semiconductor materials are mainly silicon carbide (SiC) and gallium nitride (GaN).
The fourth - generation semiconductor materials refer to semiconductor materials with extreme bandgaps, including two categories: ultra - wide bandgap (UWBG) and ultra - narrow bandgap (UNBG). Among them, the bandgap of ultra - wide bandgap semiconductor materials exceeds 4 eV, and they can withstand harsh environments such as high voltage, high temperature, and high radiation. Diamond is one of them, and there are also gallium oxide, aluminum nitride, etc. The bandgap of ultra - narrow bandgap semiconductor materials is less than 0.5 eV, and they can achieve excellent performance such as low power consumption, high sensitivity, and high speed. Representative materials include gallium antimonide, indium arsenide, etc.
Diamond has a bandgap of about 5.5 eV. It is the material with the highest performance among the fourth - generation materials and is regarded as the "ultimate semiconductor material". It has excellent thermal conductivity, 13 times that of silicon, and is suitable for high - frequency, high - power, and high - temperature electronic devices.
As silicon - based semiconductors approach the physical limit of "Moore's Law", the third - generation semiconductor materials have become the key direction for the industry to break through. After silicon carbide and gallium nitride, diamond semiconductors, with the triple characteristics of "ultra - wide bandgap, ultra - high thermal conductivity, and ultra - strong voltage resistance", are opening up new imagination spaces in fields such as high - power, high - frequency, and extreme environments.
In high - power scenarios, "heat dissipation" and "voltage resistance" are the two core pain points. Traditional silicon devices are prone to overheating and losing control under high voltage and large current. Although silicon carbide has improvements, it still cannot meet the needs of next - generation high - power devices. The ultra - high thermal conductivity and excellent breakdown field strength of diamond semiconductors happen to be the key to solving this pain point.
As new energy vehicles are upgraded to the 800V high - voltage platform, the short - comings of traditional silicon - based IGBTs (Insulated Gate Bipolar Transistors) in voltage resistance and heat dissipation are becoming more and more obvious. Diamond can withstand higher voltages, directly improving the performance and safety of the whole vehicle.
In the field of high - frequency communication, the "frequency limit" and "signal loss" are the keys restricting performance. The high carrier mobility of diamond semiconductors is making it an "ideal carrier" for high - frequency signal transmission. For example, it plays a role in applications such as radar systems and satellite communications.
The diamond - based gallium nitride heterojunction device can achieve a performance breakthrough of reducing the junction temperature by 50% and increasing the power density by 3 times through interface thermal resistance optimization. The reliability of this type of device has been verified in low - orbit satellite communication modules and 5G millimeter - wave base stations.
In terms of quantum computing, the color centers in diamond, especially the NV centers, can be used as qubits due to their unique quantum properties and are used to perform operations in quantum computing. Secondly, the color centers in diamond have extremely high quantum manipulation accuracy, which is crucial for building high - performance quantum computers. The qubits in diamond can also operate at room temperature, which is in contrast to many other quantum computing platforms that require extremely low - temperature environments, helping to reduce the complexity and cost of quantum computing systems.
Japan, Leading the Way
Japan's progress in diamond semiconductor technology is remarkable. It is expected that multiple practical applications will be realized between 2025 and 2030.
Saga University in Japan has been at the forefront of this innovation. In 2023, it developed the world's first power device made of diamond semiconductors. This breakthrough was achieved in cooperation with the Japan Aerospace Exploration Agency (JAXA), focusing on high - frequency components for space communication.
In addition, Orbray, headquartered in Tokyo, has developed mass - production technology for 2 - inch diamond wafers and is moving towards the goal of realizing 4 - inch substrates. Once the commercialization of 4 - inch diamond substrates is achieved, it will solve a key bottleneck in production, making the feasibility of widespread industrial applications a step closer and enabling Japan's semiconductor industry to set new standards globally.
Orbray is also cooperating with Anglo American plc to promote its synthetic diamond substrate business, focusing on the development of large - diameter diamond substrates for power semiconductors and communication. The company plans to expand its production facilities in Akita Prefecture, Japan, and is expected to conduct its initial public offering in 2029.
Power Diamond Systems, a Japanese startup spun off from Waseda University, successfully developed a technology in 2023 to improve the current - carrying capacity of diamond power devices. The company plans to launch samples in the next few years and has established a partnership with Kyushu Institute of Technology.
The potential for the accelerated commercialization of diamond semiconductors has attracted more attention to related businesses. For example, JTEC specializes in producing precision equipment for research institutions and has developed a plasma technology for polishing the surfaces of high - hardness materials.
EDP is the only company in Japan engaged in the production and sales of synthetic diamond seeds for gemstones and has the world's largest single - crystal production mechanism. The company is also engaged in the production of diamond semiconductor substrates and tool materials.
With the development of diamond semiconductor technology, the quality and stable supply of synthetic diamond have become increasingly important. Sumitomo Electric Industries produced the world's largest synthetic diamond single crystal in the 1980s, named "SumiCrystal", using high - quality materials for industrial applications.
In recent years, some diamond semiconductor startups have emerged in the United States. Most of these companies use years of academic R & D expertise to promote the commercialization of semiconductor diamond devices. For example, Diamond Foundry, Diamond Quanta, Advent Diamond, etc.
Accelerating the Industrialization of Domestic Diamond Semiconductor Technology
In January 2024, according to the official website of Xi'an Jiaotong University, the research team led by Professor Wang Hongxing of Xi'an Jiaotong University independently developed 2 - inch heteroepitaxial single - crystal diamond self - supporting substrates through 10 years of painstaking research using microwave plasma chemical vapor deposition (MPCVD) technology and successfully achieved mass production, reaching the world - leading level.
In December 2024, the Dongguan Institute of Optoelectronics of Peking University released the latest research results. A joint research team composed of the institute, Southern University of Science and Technology, and the University of Hong Kong made important progress in the preparation and application of diamond film materials and successfully developed a preparation method capable of mass - producing large - size, ultra - smooth, and flexible diamond films.
In February this year, the team led by Professors Liu Bingbing and Yao Mingguang of Jilin University, in cooperation with Professor Zhu Shengcai of Sun Yat - sen University, published a paper in the international top - tier journal "Nature Materials", announcing the first successful synthesis of high - quality hexagonal diamond bulk materials. Its hardness and thermal stability far exceed those of traditional cubic diamond. By simulating the extreme environment of a meteorite hitting the Earth's core (ultra - high pressure of 50 GPa and 1400°C), the team found that graphite can be transformed into hexagonal diamond, with a hardness of 155 GPa, 40% higher than that of cubic diamond, and its thermal stability exceeds 1100°C.
In the same month, when answering investors' questions on the interactive platform, Northern Huachuang said that it is closely following the research progress in the field of fourth - generation semiconductors and can provide research - type equipment such as crystal growth, etching, and thin - film deposition for research institutions.
Huawei has also shown in - depth layout in the field of diamond chips. In 2024, Huawei and Harbin Institute of Technology jointly applied for a patent for "a hybrid bonding method for a three - dimensional integrated chip based on silicon and diamond". This technology uses Cu/SiO2 hybrid bonding technology to three - dimensionally integrate silicon - based and diamond substrate materials, providing a heat - dissipation channel for three - dimensionally integrated silicon - based devices and improving the reliability of the devices.
Huawei has also cooperated with Xiamen University and made breakthrough progress in the integrated chip - diamond heat - dissipation technology of advanced packaging glass interposers. When the power density of the chip hot - spot is about 2 W/mm², the integrated diamond heat - dissipation substrate can reduce the maximum junction temperature of the chip by up to 24.1°C and reduce the thermal resistance of the chip package by 28.5%.
In addition to the research progress of scientific research institutions, some enterprises in China are also accelerating the industrialization of diamond semiconductors.
Among listed companies, the main enterprises in synthetic diamond include LiLiang Diamond, Huanghe Whirlwind, Huifeng Diamond, Sinomach Precision Industry, Zhongbing Hongjian, Sifangda, Wald, Guangpu Co., Ltd., Hengsheng Energy, etc.
Zhongbing Hongjian said that the company's functional diamond products can be used in fields such as semiconductors, optics, heat dissipation, and quantum.
Huanghe Whirlwind said that the company's technology in the field related to diamond semiconductors is still in the R & D stage.
Wald said that the company focuses on the research of diamond functional materials in tool - grade, heat - sink - grade, optical - grade, and electronic - grade aspects.
A wholly - owned subsidiary of LiLiang Diamond signed a project on high - power diamond semiconductors for semiconductors with Jiesiao Enterprise Co., Ltd. in Taiwan, China, and is committed to researching functional diamond materials for semiconductor heat dissipation.
Guangpu Co., Ltd. said that the diamond heat - sink chips of the company - invested Huajie Jidian can be used for chip heat dissipation.
Hengsheng Energy said that its subsidiary Huamao Technology will actively conduct R & D on the application of diamond in semiconductor wafers.
In the semi - annual reports of many new material and equipment enterprises in the first half of 2025, diamond has gradually been included in the R & D and industrialization directions of more enterprises. Three companies, Tianyue Advanced, Srui New Materials, and Zhishang Technology, have maintained development in their main businesses such as silicon carbide substrates, copper - based alloys, and equipment manufacturing, and at the same time, they have carried out exploration in diamond - related fields. Combining with future technological trends such as AI computing power, optical communication, new energy, and semiconductors, the potential of diamond is being released at an accelerated pace.
Tianyue Advanced is conducting research on single - crystal diamond growth through the MPCVD method, trying to break through the technical bottleneck of large - size, high - quality substrate preparation, and improving the processing ability with laser cutting and step - by - step processing technology. Srui New Materials has also clearly proposed to layout the R & D of copper - diamond materials. Zhishang Technology's semiconductor polishing equipment can be applied to the grinding and polishing of silicon carbide, silicon nitride, quartz glass, and diamond.
Four Challenges in Diamond Industrialization
Currently, diamond semiconductors are at a critical stage from R & D to practical application. Although certain application results have been achieved in fields such as heat - sink substrates and radiation detectors, they still face many challenges.
Material growth is the primary problem in the industrialization of diamond semiconductors. The current mainstream 12 - inch silicon wafers have achieved large - scale application, which can significantly reduce the unit cost of chips. However, the size of diamond single - crystal substrates is far less than 8 inches, directly limiting the chip integration and production volume. Small - size substrates not only cannot meet the high - density layout requirements of large - scale integrated circuits but also increase the shared costs such as equipment depreciation and raw material consumption, weakening the price competitiveness.
There are also bottlenecks in the preparation technology. Chemical vapor deposition (CVD) is the mainstream method, but the growth rate is only a few microns to dozens of microns per hour, which is difficult to meet the efficient production needs of the semiconductor industry. Moreover, it requires precise control of multiple parameters, and the equipment and operation costs are high. Although the high - temperature and high - pressure method (HTHP) can produce diamond, it is easy to introduce impurities and defects and cannot be directly used for semiconductors. The crystal quality and uniformity of diamond prepared by the CVD method still need to be improved.
In terms of doping technology, both p - type and n - type are in trouble. P - type doping mainly relies on boron atoms, but the ionization energy of boron is as high as 0.37 eV, and it is difficult to be completely ionized at room temperature, resulting in an extremely low carrier concentration. If heavy doping is carried out to increase the concentration, it will lead to an increase in lattice stress and surface defects, intensify electron - hole recombination, and increase the device turn - on voltage and on - resistance.
In theory, phosphorus atoms can be used for n - type doping, but its atomic radius is much larger than that of carbon atoms, and doping will cause serious lattice distortion. This distortion will greatly increase the probability of carrier scattering, resulting in a sharp decline in mobility. At present, it is still difficult to obtain high - concentration and high - quality n - type doped diamond, which limits the application of related devices.
However, some experts predict that in the next 3 - 5 years, 4 - inch diamond substrates are expected to achieve mass production, and their excellent electrical conductivity characteristics are expected to solve the global problem of the lack of efficient p - type devices in wide - bandgap semiconductors.
In device manufacturing, the compatibility between traditional semiconductor processes and diamond is poor. In the photolithography process, the surface characteristics of diamond are special, and ordinary photoresists are difficult to adhere uniformly, which is likely to cause pattern distortion and uneven lines. In the etching process, diamond has extremely strong chemical stability, and most traditional etchants have weak effects, making it difficult to precisely control the etching depth and shape.
The ultra - hard characteristics of diamond also pose challenges to processing. Silicon and silicon carbide polishing wafers need to reach atomic - level flatness (roughness RMS ≤ 0.1 nm). However, due to the extremely high hardness of diamond, ordinary grinding tools wear out quickly. Even when using diamond grinding wheels, there are still problems such as low efficiency and easy thermal damage, making it difficult to meet the "substrate - grade" surface quality requirements.
This article is from the WeChat public account "Semiconductor Industry Insights" (ID: ICViews), author: Feng Ning, published by 36Kr with authorization.