Spänt germanium: Ett genombrott för kvantchip

Från kisel tillbaka till germanium

Silicon-based semiconductors are increasingly reaching multiple technical limits. Not only are transistors in the most advanced chips made of merely a few atoms, but the very physical characteristics of silicon atoms are becoming a limitation that cannot be overcome for further improvements.

This is especially true for the most advanced forms of computing, such as spintronics and quantum computing.

As a result, researchers and semiconductor companies are turning to other metals and elements to find new potential designs.

One in particular, germanium, is enjoying renewed popularity. First used in the 1950s in the earliest transistors, it was initially replaced by silicon thanks to factors like production costs and ease of manufacturing.

Today, germanium, which is crucial for electronics and infrared optics—including sensors on missiles and defense satellites—is mostly produced from zinc and molybdenum mines.

It could also be used for other applications; for example, magnetiska järn‑germaniumkristaller forming unique structures could be used to create superconductors. Filmer gjorda enbart av germanium kan också vara supraledande.

But germanium also has unique physical properties that make it a potential replacement for silicon semiconductors in specific cases.

Researchers at the University of Warwick and the National Research Council of Canada found that germanium can be more than 15,000x better than silicon in some aspects. They published their results in Materials Today, under the title “Hålrörlighet i komprimerat spännt germanium på kisel överstiger 7 × 10⁶ cm²·V⁻¹·s⁻¹”.

Flytta hål, inte elektroner

When dealing with electronics and semiconductors, the exact atomic structure of a material can be as important as the elements of which it is made.

This is the case with germanium as well. The researchers created a nanometer-thin germanium layer that is compressively strained and grown on silicon.

The idea is to optimize the transport of electric charges using “high-mobility holes”, instead of the usual movement of electrons.

In this case, instead of electrons moving and carrying information, we measure the property representing how easily positive charge carriers (“holes,” or missing electrons) move through a material under an electric field.

Compared to traditional electron movement, hole mobility has superior “stark spin‑bana‑koppling, undertryckt hyperfin interaktion och effektiv hel‑elektrisk spinkontroll”.

In less technical language, this means that this property is perfect for encoding information in spintronic and quantum computing systems.

But until now, hole mobility materials were too vulnerable to disturbance from the environment to be useful for actual computing. Impurity and difficult manufacturing hindered this idea further.

Komprimerat germanium

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A new production method has recently emerged, called compressive strain, which alters semiconductor materials’ crystal structure, influencing electron energy levels and charge transport.

Using this method, the researchers managed to create a thin layer of compressed germanium onto a layer of silicon, which displayed a hole mobility of 7.15 million cm² per volt-second (compared to ~450 cm² per volt-second in industrial silicon).

This represents an exponential improvement over germanium-based electronics for this metric.

Källa: Materials Today

Because the electric charges can move significantly faster (>15,000x) in this material, this opens the door to creating electronics that are much faster and much less energy-consuming.

“Detta sätter en ny referenspunkt för laddningstransport i grupp‑IV‑halvledare – materialen i hjärtat av den globala elektronikindustrin.

Det öppnar dörren till snabbare, mer energieffektiva elektronik‑ och kvantenheter som är fullt kompatibla med befintlig kiselteknik.

Dr. Sergei Studenikin – Principal Research Officer, National Research Council of Canada

Hur spännt germanium kan driva kvant- och lågenergi‑chip

This new cs-GoS platform is inherently compatible with CMOS technology (Complementary Metal-Oxide-Semiconductor), a staple of semiconductor manufacturing used for sensors, low-power circuits, and PC memory.

It can also be scaled up to a wafer-size layer, making it directly applicable to current semiconductor manufacturing methods.

“Traditional high-mobility semiconductors such as gallium arsenide (GaAs) are very expensive and impossible to integrate with mainstream silicon manufacturing.”

Dr. Sergei Studenikin – Principal Research Officer, National Research Council of Canada

It opens the way for using hole mobility in quantum computer designs, or integrating this type of germanium-based circuit in low-energy consumption chips and spintronic devices.

So the conversion of a lab prototype to a working mass-produced chip should not be as difficult as is often the case for more exotic designs.

Källa: Materials Today

“Our new compressively strained germanium-on-silicon (cs-GoS) quantum material combines world-leading mobility with industrial scalability — a key step toward practical quantum and classical large-scale integrated circuits.”

Dr. Sergei Studenikin – Principal Research Officer, National Research Council of Canada

Investera i tillverkning av halvledare

TSMC – Taiwan Semiconductor Manufacturing Company

Semiconductor production is an industry dominated by the combination of very niche and complex expertise, and the need to mass-produce at scale to reduce costs.

No company has been as successful at mastering this business model as TSMC, the Taiwanese company leading the world in the manufacturing of ultra-advanced chips.

TSMC primarily produces silicon chips, including the most powerful 3nm and 2nm node chips. And as it produces the most advanced and expensive chips, it controls more than half of the global revenues of the semiconductor foundry industry.

Källa: Eric Flaningam

TSMC is currently evolving to start producing silicon chips in the US, särskilt med en massiv investering i sina nya Arizona‑foundries.

Still, TSMC is also an expert at advanced germanium-based transistors and other semiconductors.

So while the company is mostly driving its current profit from advanced chips and the manufacturing of AI-hardware for the likes of Nvidia (NVDA ), it could also be one of the main beneficiaries of the discovery that common semiconductor manufacturing methods can produce high-performance chips, including those using germanium.

(You can also read more about TSM’s history and business in our investment report dedicated to the company.)

Senaste TSMC (TSM) aktienyheter och utvecklingar

Studie refererad:

^{1. Myronov, M., Bogan, A., & Studenikin, S. (2025). Hålrörlighet i komprimerat spännt germanium på kisel överstiger 7 × 10⁶ cm²V⁻¹s⁻¹. Materials Today, 90, 314–321. https://doi.org/10.1016/j.mattod.2025.10.004}