GaN power semiconductors have recently entered a new stage of development regardless of market applications or technological progress. Coupled with the catalysis of a single-type integrated process of research institutions, the market outlook is expected to gradually grow from the power supply market.
Gallium nitride (GaN) power semiconductors are expected to be a big city. With the advent of the 5G and AIoT era, many innovative technology applications such as self-driving cars, electric vehicles, wireless charging, augmented reality (AR), industrial intelligence, drones, and even 5G base stations will significantly increase energy efficiency requirements. . GaN technology, which can achieve higher conversion efficiency than today's silicon (Si) power devices, has become the focus of attention from all walks of life, and has attracted many semiconductor players to invest in the layout.
According to market research institution Yole Développement, compared with the $ 32.8 billion output value of silicon power semiconductors, the GaN power market is still quite small, but the technology has begun to penetrate into various application areas, among which power supply is the main application. Such as the fast charger for mobile phones.
It is understood that Anker can be said to be the most active manufacturer of mobile peripheral devices to introduce GaN power technology on the market. Its mobile charger PowerPort Atom PD is the first to third generation, as well as some PowerPort products, and another PowerCore Fusion , Have begun to introduce GaN technology. In addition, manufacturers such as Aukey, RavPower, Mu One have also adopted.
In addition to mobile chargers, LiDAR, data center servers, electric vehicles, and wireless charging are also growing applications for GaN power semiconductors. Yole believes that GaN power semiconductors can bring higher energy-saving benefits, so the R & D energy of related technologies has continued to increase, and commercial products have also begun to come out. The overall GaN power component market size has gradually increased since 2016; if the situation is optimistic, it is estimated that 2017 The compound growth rate (CAGR) from ~ 2023 can reach 93%, reaching a scale of US $ 423 million.
Large factories join the mass production ranks
In June 2018, Infineon, a large power semiconductor manufacturer, officially announced that it will begin mass production of CoolGaN 400V and 600V e-mode high electron mobility transistors (HEMT) at the end of the year.
Yole Technology and Market Analyst Ezgi Dogmus believes that the announcement of the start of mass production of GaN by this power solution leader is an important symbol for the GaN power device market. Infineon already has many customers using their silicon solutions, and these customers have the opportunity to migrate to GaN technology in the future.
Not long after Infineon announced the mass production of GaN, STMicroelectronics also announced that it would expand from the original development of silicon carbide (SiC) to the field of GaN technology and will cooperate with the French technology research institute CEA-Leti Developed GaN-on-si technology and used Leti's 8-inch R & D line for diode and transistor development. Both parties expect to complete the validation project samples in 2019. At the same time, STMicroelectronics also expects to build a fully compliant production line (including GaN-on-Si heteroepitaxial process) in the company's former wafer fab in Tours, France in 2020, as an initial production Use.
In addition to the growing strength of integrated component manufacturers (IDMs), new companies focusing on GaN power component developers have also emerged in recent years. The aforementioned EPC, Transphorm, and GaN Systems were established relatively early. There are also Tagore, Exagan, Navitas, VisIC, Dialog Semiconductor, GaNPower International, NEXGEN Power Systems and domestic InnoSec.
Most of these start-ups are Fabless companies, and they choose to use the business model of outsourcing production to fabs. Most of them use TSMC, Episil or X-Fab as their main choice. In the future, once the market scale expands, the business model of foundry will allow these fabless startups to grow rapidly. Of course, there are also some IDM manufacturers in the new GaN companies, which is more common in China, and InnoSec is one of them.
At present, integrated GaN power devices on the market can be roughly divided into two types. One is the integration at the packaging level. Integrating GaN transistors and drivers into a single package will mostly target applications above 650V. The integration of GaN transistors and drivers is also called so-called Monolithically Integrated. Such product suppliers are represented by EPC and Navitas, which are mostly targeted at consumer applications below 600V.
Due to the huge demand for consumer applications such as mobile device chargers, it is an important nutrient for GaN players. Therefore, in order to meet the design requirements of the market's lightweight appearance, it is imperative to move towards a highly integrated design solution.
imec process technology assists GaN to achieve monolithic integration
In view of the market's development needs for higher integration GaN power components, nanoelectronics and digital technology research and innovation center imec, using its GaN-on-SOI and GaN-on-QST technology platforms, released a single driver and driver Integrated and fully functional GaN half-bridge IC.
A half-bridge is a secondary circuit commonly found in power systems and is composed of discrete components, especially for applications in the higher voltage range. To use GaN-on-Si technology to implement a half-bridge circuit on a chip is very challenging, especially for high-voltage design. This is because a half-bridge circuit designed based on GaN-on-Si technology will have a "back-gate effect." (Back-gating Effect) ", which in turn negatively affects the high-side switch of the half-bridge circuit, and switching noise will also cause interference to the control circuit and inhibit overall performance.
imec's solution is based on imec's GaN-on-SOI and GaN-on-QST technology platforms. Through buried oxide and oxide-filled deep trench isolation designs, power components, drivers, and The control logic can be electrically isolated. This isolation mechanism can reduce the negative impact of the harmful back-gate effect on the high-side switch of the half-bridge, and can reduce the interference of switching noise on the control circuit.
In addition, imec's technology platform also integrates a level shifter (used to drive high-side switches), a dead-time controller (used to avoid repeated gate input waveforms), and Pulse width modulation circuit to achieve a highly integrated buck-boost converter.
Imec business development manager Denis Marcon said that some people might think that using SOI or QST wafers to replace silicon wafers will result in more expensive technology. However, with GaN-on-Si technology, many discrete components must be individually packaged (using advanced packaging to improve GaN's fast switching performance) and connected to their drivers and other components at the board or package level. In contrast, the use of imec's GaN-IC technology can achieve a complete converter and integrate the driver and analog circuit blocks, which can be packaged by simple packaging technology (because frequency-sensitive components have been Link), which will save the cost of the final power system.
Stefaan Decoutere, director of imec GaN's power electronics program, said that by reducing parasitic inductance and intangible size reduction, high-end power systems will have the potential to significantly improve performance in terms of switching speed, operating frequency, or energy efficiency. It is expected to further enhance the use of GaN in consumer power supplies and renewable energy.