The space industry is undergoing a transformative shift to “New Space,” driven by the increasing demand for ubiquitous connectivity and the emergence of innovative business models. One of the key elements of this transformation is the adoption of gallium nitride (GaN) technology in space applications. GaN holds immense potential due to its impressive radiation hardness, high system efficiency and lightweight characteristics.

In a discussion with EE Times Europe, technology and market analysts at Yole Intelligence, part of Yole Group, explained how New Space—the low Earth orbit (LEO) mission segment, with a typical satellite lifespan of three to five years and lower reliability requirements—has become a focal point for GaN adoption. As a result, power GaN devices are being adopted for various satellite systems, including DC/DC converters, point-of-load systems, motor drives and ion thrusters.

The space market for power GaN devices is expected to exceed US$28 million by 2028, with a 26% CAGR from 2022 to 2028, according to Yole Intelligence’s Power GaN 2023 report. “As of 2023, the power GaN market for space applications is dominated by non-EU players, such as U.S.-based EPC Space and Canada’s GaN Systems [which, in March 2023, accepted an offer to be acquired by Infineon],” Ayari and Ghorbel said. “GaN Systems is partnering with Teledyne to provide space-grade products. For the EU, it is mainly the satellite and system makers, such as Airbus and Thales Alenia, that are actively working on power GaN projects. As of 2023, there is no European power GaN device supplier for the space industry.”

In parallel, satellite communication has emerged as a significant market for radio-frequency (RF) GaN technology. This segment is expected to reach a market size of US$270 million by 2028, with a substantial CAGR of 18% from 2022 to 2028, according to Yole Intelligence’s RF GaN 2023 report. RF GaN power amplifiers (PAs) have become instrumental in enabling higher data throughput, reducing antenna size, increasing bandwidth and enhancing overall efficiency in satellite communication.

GaN vs. other semiconductor materials for space applications
GaN has become a potential choice for use in space. It has especially shown promise in two key areas: power GaN high-electron–mobility transistors (HEMTs) and RF GaN PAs. Traditional silicon (Si) MOSFETs don’t work as well as power GaN HEMTs in terms of radiation tolerance or hardness, which have better efficiency and smaller form factors at the system level. In addition, GaN devices cost less to manufacture than their silicon counterparts. Si MOSFETs are usually made in dedicated, low-volume lines with specific designs for space uses. GaN devices for space can share production lines with high-demand applications like cars, reducing costs. GaN is a good choice for power uses in space systems because it is both cost-effective and more efficient.

According to Yole Intelligence, from the perspective of RF GaN technology, GaN high-power amplifiers demonstrate exceptional characteristics for uplink transmitters in satellite communication systems. They offer high output power, high power-added efficiency, ruggedness and durability.

“As of 2023, satellite communication systems mainly use GaAs power amplifiers due to their low cost,” Ayari and Ghorbel said. “On the other hand, GaN-based power amplifiers could offer attractive performance/cost ratios as well as superior thermal management compared with GaAs solutions. Over the 2020–2023 period, GaN has gained market share since its performance meets the new requirements going to higher frequencies. GaN technology can afford higher data throughput, larger bandwidth to cover more spectrum with better efficiency, and smaller antenna size.”

Competitive landscape for GaN technology
As of 2023, the market for space applications in the EU is beginning to offer a competitive landscape of interest for GaN technology. While Yole Intelligence has not identified any active EU-based power GaN device manufacturers for space applications, several major competitors are active in the RF GaN market. These include Ommic, which is now a subsidiary of U.S.-based Macom, UMS, Ampleon, Altum RF and others, who all offer GaN PAs designed for aerospace applications.

Ommic
Ommic’s GaN-on-Si technology is unusual in the RF GaN industry: It is an advanced technology node of 40 to 100 nm. The RF GaN industry standard, GaN-on-silicon-carbide (SiC), competes with this technology and is more common.

STMicroelectronics
STMicroelectronics is currently heavily invested in GaN technology, with two GaN fabs in Europe: one for power GaN in Tours, France, and one for RF GaN in Catania, Italy. ST’s goal is to become a key global supplier of GaN semiconductors, and ramping up production in these fabs is critical.

In research and development, ST is focusing heavily on power and RF GaN, which are known for their excellent resistance to total-dose radiation and single-event effects (SEEs). While not developing GaN technology solely for space, ST is conducting radiation testing on its parts to ensure suitability for space applications.

Recognizing the market trends for GaN technology in the European space industry, ST notes that GaN is becoming essential for LEO satellites, especially for points of load and power generation and distribution. The company sees the industry currently in an early adoption phase but anticipates wider adoption and integration with system-in-package (SiP) and system-on-chip (SoC) technologies in the future.

ST’s future strategy aligns with the broader semiconductor market, focusing on providing high-quality GaN products to high-volume customers at competitive prices. The company plans to continue its GaN deployment strategy and explore product integration with SiPs and SoCs.

Overall, ST plays a significant role in shaping the European space industry by offering GaN technology alongside other semiconductor solutions, contributing to the growth and competitiveness of the EU space industry, from LEO to deep-space missions.

EPC Space
EPC and EPC Space are actively involved in advancing GaN technology for space applications. Over the past four years, EPC Space has focused on the development of radiation-hardened GaN devices, both in hermetically sealed packages and chip-scale packaging. EPC’s ongoing research efforts include valuable physics of failure studies to enhance reliability predictions, making its GaN epitaxy increasingly robust for space use.

EPC Space has developed a range of discrete GaN devices with voltage ratings from 40 V to 300 V, offered in various packages ranging from 8.9 mm2 to 44.8 mm2, including compact chip-scale options. It has successfully tackled challenges related to SEE immunity in its rad-hard devices. Collaborations with a key European space partner have been instrumental in achieving these milestones.

GaN technology is gaining momentum, with increasing interest from European companies and the European Space Agency (ESA) for its potential in space power applications. EPC Space envisions a future where GaN becomes the standard in satellite power design, offering more efficient, smaller and more cost-effective solutions, thus contributing significantly to the competitiveness and growth of the EU space industry.

“Power GaN technology in the EU is new, but it’s finding good traction, as many EU companies and the ESA are conducting reliability testing to understand more about GaN device physics and to see how GaN can be utilized effectively for space applications,” said Bel Lazar, CEO of EPC Space. “Our prediction is that direct shipment of GaN to EU countries will start seeing volume deliveries in 2024 and by 2025–2026, it will be used in most of the new power designs for space.”

Emerging startups and disruptive technologies
While the power GaN industry has seen the emergence of several startups and companies, those companies’ primary focus tends to be on high-volume markets with relatively fast time-to-market requirements.

In the RF GaN industry, which is more established, there have been fewer newcomers in recent years. One notable exception is Gallium Semiconductor, although it’s worth mentioning that this company is located outside the EU. The RF GaN sector has reached a level of maturity with established players, and the emergence of disruptive technologies or startups with a significant impact on the EU-based space application market remains limited in 2023.

Technology assessment and challenges
In recent years, the EU has seen technological advancements and innovations in GaN for space applications. These developments encompass various aspects of GaN technology, including substrates, devices and the establishment of a foundation for a robust ecosystem.

Starting with substrates, Yole said that SweGaN, a spinoff of Linköping University (Sweden), specializes in the epitaxy of GaN-on-SiC substrates, which are crucial for both RF and power applications. This technology allows for high-quality GaN material growth, enhancing the performance of GaN-based devices.

“On the device front, Ommic has set itself apart by delivering RF GaN power amplifiers capable of addressing high frequencies up to Ku/Ka bands,” Ayari and Ghorbel said. “Their advanced technology nodes of 40, 60 and 100 nm for GaN-on-Si enable the development of high-performance RF components, essential for space communication and satellite systems.”

Additionally, European Altum RF, along with Chinese-Dutch Ampleon and European UMS, are notable players offering GaN-on-SiC technology. GaN-on-SiC has become something of a standard in the RF GaN industry due to its exceptional performance characteristics, making it a crucial technology for space applications.

Yole said that the EU has carefully focused on building a European power GaN ecosystem that includes design, production, processing, qualification/testing and more. This is because the space industry is very sensitive to geopolitics. EleGaNT, SAGAN and SCOPS are some of the groups that have gotten funding to help with this effort. The goal of these projects is to encourage teamwork and new ideas in the European GaN space sector. This will help create cutting-edge technologies and meet the high standards for quality and dependability that are needed for space missions. Yole Intelligence finds a number of important challenges and opportunities in the GaN space market in the EU, mainly when it comes to space applications.

Challenges
Cost-effective manufacturing: Making GaN-based parts for space uses that don’t cost too much is one of the biggest problems in the EU GaN space market. The space industry needs materials that are both high-performance and resistant to radiation. However, it is still hard to find materials that are cost-effective and that keep these qualities.

Supply chain vulnerabilities: Space projects may be at risk because they need a global supply chain to get GaN materials and parts. It is very hard to make sure that the supply chain for important GaN parts is safe and reliable.

Regulatory compliance: The space industry operates under stringent regulations and standards. Adhering to these regulations while pushing technological boundaries with GaN-based systems can be a complex task.

Integration complexity: It can be difficult to integrate GaN technology into extant space systems and architectures. Compatibility concerns and the requirement for exhaustive testing and validation can hinder the adoption of GaN-based solutions.

Opportunities
Satellite communications growth: The increasing focus on satellite communications presents a significant opportunity for the EU GaN space market. With the advent of the New Space sector, there is a growing demand for high-performance GaN-based RF and microwave devices to enable advanced satellite communication systems.

5G coverage via satellites: Space X’s plans to provide 5G coverage through satellite technology open up new opportunities for GaN-based components. GaN amplifiers and transceivers can play a crucial role in achieving high-speed and reliable satellite-based 5G connectivity, especially in remote or underserved areas.

Global connectivity: GaN technology can help bridge the digital divide by providing reliable phone network coverage in remote and rural regions. The EU GaN space market can contribute to the vision of a world where everyone has access to seamless communication services.

Space exploration: GaN-based components can enhance the performance of spacecraft, enabling advanced scientific missions, deep-space exploration and improved satellite constellations. These opportunities align with the EU’s ambitions in space exploration and technology development.
R&D and innovation: The EU has a strong tradition of R&D in semiconductor technologies. Investing in GaN research and innovation can position the region as a leader in advanced space technology, fostering economic growth and technological leadership.

Regulatory evolution and GaN adoption: navigating the New Space paradigm
In the fast-changing New Space industry, the expanding preference for commercial off-the-shelf components is reshaping regulatory standards and certifications. For Yole Intelligence, this transition toward more flexible regulations and increased integration with terrestrial applications, such as automotive, is accelerating the adoption of GaN technology. GaN’s allure rests in its capacity to expedite development timelines and simplify the historically complex qualification processes mandated by government agencies in the conventional space industry. Existing protocols are primarily intended for silicon technology. However, as GaN acquires popularity, there is a pressing need for customized testing procedures, particularly for power GaN devices, as they are primarily designed for silicon technology. To capitalize on the full potential of this transformative trend, businesses operating in the GaN space sector must remain vigilant and adaptable to these regulatory shifts.

This article is reprinted from EETimes.