The RF power supply is a high-frequency power supply that can generate a fixed frequency sine wave and a certain frequency. It is mainly composed of a RF signal source, a RF power amplifier and an impedance matcher. It is a supporting power supply for plasma. Among them, RF power amplifier is considered to be the core of RF power supply, so RF power amplifier is a key factor restricting the development of RF power supply.
Depending on the type of power amplifier used, RF power supplies can be divided into tube RF power supplies and transistor RF power supplies. From the tube RF power supply in the 1980s to the current transistor RF power supply, RF power supplies have experienced a long development process. The power ranges from watts, hundreds of watts, kilowatts, to megawatts, and the frequencies include 2, 4, 13.56, 27.12, 40.68MHz, 60MHz and other different ranges. At present, RF power supplies are widely used in semiconductor process equipment, LED and solar photovoltaic industries, plasma generation in scientific experiments, RF induction heating, medical cosmetology, and atmospheric pressure plasma disinfection and cleaning.
The development of radio frequency power amplifiers was relatively slow. It was not until the emergence of electron tubes in 1904 that they began to be officially used in various fields. The electron tubes themselves had many problems - first of all, their size was too large, which limited the application of tube RF power supplies in some precision fields. ; Secondly, the life of the tube RF power supply is less than half that of the transistor RF power supply; and the most important thing is that its manufacturing process is very complex. Compared with electronic tubes, transistor RF power supplies are much smaller in size. At the same time, they have low losses, long life, and generate very little heat. Therefore, with the development of transistors, electronic tubes are gradually being eliminated.
Main characteristics of the development of semiconductor RF power supply industry
1. With the development of power electronics technology, radio frequency power supplies have developed from electron tube power supplies to the current transistor radio frequency power supplies. As a typical representative of the third generation of wide bandgap semiconductor materials, gallium nitride GaN has a wide bandgap, high critical breakdown field strength, high electron saturation drift velocity and high conduction AlGaN/GaN heterojunction two-dimensional electron gas 2DEG Etc. Compared with silicon power devices, GaN power devices have the characteristics of low on-resistance and small input/output capacitance. These characteristics enable GaN power devices to have high switching speed and low loss. Based on the Class E power RF power supply, an all-solid-state RF power supply experimental prototype with a switching frequency of 4 MHz and adjustable power was designed and produced using GaN power devices. Through circuit design and optimization, when the output power of the prototype is 21.4 W, the efficiency reaches 96.7%. At the same time, Si power devices specially produced for radio frequency power supplies are used to replace the GaN devices on the prototype. The experimental data verifies the switching speed of the GaN device. It is fast and has low loss, which can greatly improve the efficiency of RF power supply.
2. RF power supply generally consists of RF signal generator, RF power amplifier circuit, power supply line and RF power detector. According to the core components of the amplifier circuit, it can be divided into tube-type RF power supply and solid-state RF power supply. The tube-type RF power supply uses electron tubes as the power amplification component, while the solid-state RF power supply uses transistors as the power amplification component. At present, the products of domestic manufacturers are mainly tube-type RF power supplies. Although they have a large impedance mismatch tolerance, they can only be used for general teaching and scientific research due to their shortcomings such as easy aging, unstable output power and high working voltage. components in the equipment. Mainstream foreign manufacturers, such as U.S. Instruments, XP Power and Wanji Instruments, all use transistors as power amplification components, and the solid-state RF power supplies they provide have been widely used in mainstream semiconductor process production lines.
3. The development of digital power supply. The control unit of the power supply is connected to the RF clock generator unit and the voltage-adjustable DC power supply respectively. The output of the RF clock generation unit and the output of the voltage-adjustable DC power supply are both connected to the power amplification unit. The power amplification unit After the power output is synthesized by the power combiner, and then the incident power and reflected power are measured by the directional coupler, the measurement signal output of the directional coupler is connected to the control unit. The power supply controls the RF power output by adjusting the height and width of the drive pulse of the power driver stage. It has high working efficiency and reliable control. Moreover, the important working parameters of the power supply can be collected and analyzed in real time through the main CPU in the control unit, and The control parameters are set through the main CPU in the control unit. If the parameters are abnormal, the power supply can be protected in time, thus greatly improving the working efficiency and reliability of the RF power supply.
Overview of the overall development of the semiconductor RF power supply industry
Semiconductor RF power supply is a high-frequency power supply that can generate a fixed-frequency sine wave and a certain frequency. It is mainly composed of a RF signal source, a RF power amplifier and an impedance matcher. The RF power supply is used as a supporting power supply for plasma, and the frequency is within the radio frequency range. Widely used in semiconductor etching, CVD and PCV fields.
At present, there is still a certain gap between the radio frequency power supplies used by my country's advanced plasma equipment and similar foreign power supplies. To catch up with the international level, a lot of work still needs to be done:
- Most of my country's RF power supplies use electron tubes or hybrid circuits of electron tubes and transistors, which are large in size and limit their application. And most of the transistors used are imported from abroad. Therefore, it is necessary to develop my country's own core transistors, develop new technologies, and new components to miniaturize the radio frequency power supply.
- Our country still uses manual impedance matching devices, which are easily affected by environmental factors. However, foreign countries have begun to use automatic impedance matching devices, which play an important role in the field of industrial automation. Therefore, high-precision, high-speed automatic impedance matching devices are the future an inevitable trend of development.
- Compared with foreign RF power supplies, the types of RF power supplies in my country are relatively single. In the future, different types of RF power supplies such as broadband power supplies, microwave power supplies, and high-power RF power supplies should be developed.
Global semiconductor RF power supply market sales and growth rate
According to statistics, global semiconductor RF power supply market sales will reach US$726 million in 2022, and are expected to reach US$1.457 billion in 2029, with a compound annual growth rate of 11.18%. From a regional perspective, the Chinese market has changed rapidly in the past few years. The market size in 2022 will be US$96.6 million, accounting for approximately 13.31% of the global market. It is expected to reach US$188.52 million in 2029, accounting for 12.94% of the global market. In the next few years, the important market position of the Asia-Pacific region will become more prominent. In addition to China, Japan, South Korea, India and Southeast Asia will also play important roles. Furthermore, Germany is expected to maintain its leading position in Europe over the next six years.
From the production side, North America and Japan are two important production regions, accounting for 36.04% and 23.17% of the market respectively in 2022. It is expected that China will maintain the fastest growth rate in the next few years, and its share is expected to reach 2029 11.71%. In terms of product types, 13.56MHz occupies an important position, and its share is expected to reach 32.1% in 2029, followed by the 27.12Mhz type. At the same time, in terms of application, the share of etching in 2022 will be approximately 36.56%, and the CAGR in the next few years will be approximately 11.09%.
In terms of manufacturers, the core manufacturers of semiconductor RF power supplies worldwide mainly include Wanji Instruments, U.S. Instruments, Japan's Osaka Transformer Co., Ltd., XP Power and TRUMPF, etc. In 2022, the world's first echelon manufacturers mainly include Wanji Instruments, U.S. Instruments, and Osaka Transformer Co., Ltd. of Japan. The first echelon accounts for approximately 52.95% of the market share; the second echelon manufacturers include TRUMPF, Comet, and Kyosan Manufacturing Co., Ltd., Northen lights Technology, ULVAC, Japan Electronics Co., Ltd., Adtec Plasma Technology, New Power Plasma, etc., occupy a total share of 33.99%.
