Silicon on insulator: from inception to cutting-edge research

Here, Electronic Specifier takes a look into the evolution of SOI technology from its early days to the breakthroughs that are shaping its future applications.

The evolution of Silicon on Insulator

SOI technology began to take shape in the late 1960s and early 1970s as researchers sought to enhance the performance and reliability of silicon-based electronic devices. By introducing a thin insulating layer, typically silicon dioxide, between the silicon layer and the substrate, engineers aimed to reduce parasitic capacitance and improve device efficiency. This structure proved advantageous, leading to a wave of innovation in semiconductor manufacturing processes.

During the 1980s, advancements such as SIMOX (Separation by IMplantation of OXygen) and BESOI (Bond and Etch-back SOI) notedly improved the practicality of SOI technology. These methods enabled better quality and more widespread applications, particularly in high-performance computing and specialised areas. By the 1990s, SOI was gaining commercial traction, with notable adoption in microprocessors and RF devices.

The 2000s marked a period of maturation for SOI technology, as it found its way into consumer electronics, automotive systems, and various industrial applications. This era saw improvements in manufacturing processes, making SOI more cost-effective and accessible. By the 2010s, SOI had become a mainstream technology, integral to the development of more compact, efficient, and powerful electronic devices.

Recent advancements in SOI technology

Recent research has propelled SOI technology into new realms, particularly in areas such as artificial intelligence (AI), quantum computing, and high-performance electronics.

One of the most notable advancements is the development of femtosecond-laser-induced colour centres in SOI substrates. Researchers have successfully created G and W colour centres using this method, which is crucial for the integration of quantum photonic devices. These colour centres enhance the performance and scalability of quantum technologies, making them more reliable and effective for quantum computing and communication applications​​.

Another development involves Fully-Depleted Silicon on Insulator (FD-SOI) technology, which is being explored for ultra-low power AI applications. Researchers at the National University of Singapore (NUS), in collaboration with industry partners like Soitec, NXP, and Dolphin Design, are working on decentralising AI computation from the Cloud to Edge devices. This approach improves privacy, reduces latency, and effectively manages data loads. The FD-SOI and IoT Consortium has been established to foster collaboration and accelerate the adoption of these technologies, ensuring rapid development and innovation in AI-connected chips​.

Additionally, the integration of high-mobility materials such as germanium and III-V compounds with SOI substrates represents another frontier in SOI research. These materials offer superior electronic properties, leading to faster and more efficient transistors. This advancement is critical for the next generation of electronic devices, providing significant performance improvements and enabling advanced functionalities​​.

The journey of SOI technology from its inception to its current state underscores its importance in the evolution of semiconductor devices. Recent advancements such as those mentioned above continue highlight the contant innovation in this field. These developments promise to drive the future of semiconductor technology, offering enhanced performance, energy efficiency, and new capabilities for a wide range of applications.

As SOI technology continues to evolve, its impact on the electronics industry will undoubtedly grow, enabling new breakthroughs and fostering the development of next-generation devices that are faster, more efficient, and more capable than ever before.