Cosmic Supply Chains

Silicon is the second most abundant element in Earth’s crust (approx. 25–28% by mass), surpassed only by oxygen; however, the atoms that make up the sand beneath our feet - and the computer chips inside our phones - were not “always here.” In the early universe, the Big Bang produced mostly hydrogen and helium; the heavier elements were cooked later, inside giant stars, and scattered across space when those stars died.

In 2025, astronomers caught an unusually revealing stellar death: a supernova named SN 2021yfj, seen from about 2.2 billion light‑years away, that had shed its outer layers before it exploded. That stripping exposed core interior material, offering rare direct evidence of where those elements form inside stars. Massive stars are often described as “onion‑like,” with layers of different elements built up over their lifetimes: lighter elements outside, heavier ones deeper in, and iron at the centre. It had previously proved difficult to observe these inner plasma layers directly - most supernova spectra (analysis measuring the wavelengths of light emitted) are dominated by outer material. SN 2021yfj was different. Researchers directly observed a thick silicon/sulphur‑rich shell expelled shortly before the dying star’s explosion, offering an unprecedented glimpse into its massive deep interior, where heavier elements are formed in advanced burning stages.

This is the origin of the raw materials that ultimately resulted in life on our planet, with silicon playing a crucial role based on its physics, chemistry and biology.

The natural wonders of silicon

Silicon sits in the Periodic Table next to carbon. Chemically, it mimics carbon’s four-bond structure but prefers forming incredibly stable silicate networks with oxygen, creating the rocks and glass that make up the Earth's crust. Physically, it maintains its integrity at extreme temperatures, making it more durable than carbon in harsh environments. In biology, while not the primary building block for life, it provides essential structural support for organisms like diatoms and certain plants.

Notwithstanding all this, one could argue silicon’s most noteworthy characteristic stems from its role as a versatile semiconductor, enabling humankind to control the flow of electrons and making it the bridge between the natural mineral world and our high-tech digital reality.

Mini supernovas on Earth

To turn silicon into modern microprocessors, chipmakers must print impossibly tiny patterns - features measured in nanometres - onto silicon wafers. EUV (extreme ultraviolet) lithography is the leading technique that enables this miniaturisation, using light at about 13.5 nanometres in wavelength, to pattern extremely fine details.

So how is this EUV light generated? One dominant approach uses laser‑produced plasma: tiny droplets of tin are shot through a vacuum chamber, hit with powerful laser pulses, and briefly turned into a hot plasma that emits EUV radiation. These bursts of radiation resemble “tiny star explosions”—not in scale, of course, but in the underlying physics: hot plasma, rapid energy release, and radiation that carries information about what the plasma is made of.

So here we find a second silicon bridge: both astrophysicists and semiconductor engineers care about what light reveals about plasma. Astronomers analyse supernova spectra to infer composition and structure—exactly how the silicon and sulphur in SN 2021yfj were identified. Meanwhile, chip engineers model how laser energy couples into tin droplets, how plasma expands, and how efficiently it emits EUV at the desired wavelength. In other words, the same physics toolkit - plasma behaviour and radiation modelling - connects these two worlds, from supernovas spanning light‑years to plasma bursts spanning millimetres.

Electrons and the Strait of Hormuz

The world’s biggest technology story – AI – is increasingly constrained not by software imagination but by physical supply chains. The US–Iran conflict and disruption around the Strait of Hormuz is triggering a major energy supply shock, and the ripple effects run straight through the world’s most concentrated semiconductor manufacturing hubs in Asia. It is estimated Taiwan holds about 66% of global advanced foundry capacity (UEV lithography), with South Korea next, while the US and China follow behind. This means the world’s most advanced chip production is disproportionately exposed to events that impact East Asian manufacturing ecosystems; power reliability, shipping, and geopolitics. Semiconductor fabrication is electricity‑intensive, capital‑dense, and schedule‑sensitive. Even small interruptions - whether from power prices, grid instability, or input shortages - can create outsize impacts because production is tightly optimised and global downstream demand (including AI) is unforgiving.

Implications for portfolios

Energy prices are becoming an increasingly significant factor influencing compute capacity. Moreover, with advanced chipmaking concentrated in a region which is highly reliant on energy imports, the AI economy inherits a geopolitical fragility that has become all too clear – this is even before we consider the China/Taiwan issue. We have entered an era where the strategic race is not only about algorithms and data; it’s about the reliable production of photons, silicon wafers and - above all - electrons.

Silicon begins life as a result of the most violent natural events we know, exploding stars.  On Earth we refashion that cosmic material using EUV light, via physics which mimic supernovas. In ‘the AI era’ energy shocks are no longer just a consumer‑price story – they are a direct risk to semiconductor throughput and therefore to the digital economy’s growth engine. When related supply routes wobble, the world’s most concentrated chipmaking base feels it first with the consequences rippling from factories to financial markets.

The modern world appears dominated by complex, futuristic, digital world themes; the rise of artificial intelligence and electrification of the global economy. However, these remain inextricably grounded by the realities of the physical world – acutely dependent on timely and efficient access to a plethora of basic materials and forms of energy. The US-Iran war and the closure of the Strait of Hormuz have brought these vulnerabilities sharply into focus – further underpinning some of our highest conviction views, expressed in client portfolios.

Sources:

https://www.bbc.co.uk/sounds/play/m002t2v2

https://www.weizmann.ca/giant-star-laid-bare-reveals-birthplace-of-silicon-and-sulphur

https://spectrum.ieee.org/euv-light-source

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