Minneslagring för hög temperatur närmar sig verkligheten med senaste genombrottet

Ultra‑hög temperatur‑elektronik

As mankind pushes its technology ever further, it keeps dealing with more and more extreme conditions, including heat. This is often handled with advanced materials like composite ceramics or special rare metals like volfram, titan, or rodium (follow the links for a detailed investing guide for each metal).

Dealing with extreme conditions gets a little more complicated when electronic components get involved. A rocket titanium shell might withstand heat but will not block the heat from entering in the long run.

Most computer chips are designed to perform complex operations at the nanometer scale, making them very sensitive to changes in temperature. And while some hardening can be done, past a certain temperature threshold, no classical electric circuit can keep functioning.

To keep electronic controls in spaceships, nuclear power plants, or drilling systems, advanced cooling systems are used to shield the electronic elements from the surrounding environment.

This is why a newly developed form of digital memory that can store and write information at temperatures over 1100°F (600°C), or the melting temperature of steel, could be a game changer.

This achievement by researchers of the University of Michigan and Sandia National Laboratories’ was published in the scientific journal device, under the title “Icke-flyktigt elektrokemiskt minne vid 600°C möjliggjort av fasseparering av sammansättning¹”.

Syrebaserat minne

This memory method works by moving negatively charged oxygen atoms rather than electrons. Above 300°F (150°C), conventional silicon-based semiconductors start conducting uncontrollable levels of current.

The result is that in classic electronics, high temperatures can wipe out information in the device’s memory. However, oxygen ions are not affected by the heat.

Hur det fungerar

The oxygen atoms are moved between two layers in the memory—the semiconductor tantalum oxide and the metal tantalum.

Källa: Cell Device

The movement is allowed by a solid electrolyte that acts as a barrier by keeping other charges from moving between the layers. The tantalum and tantalum oxide layers do not mix, similar to oil and water, so these new layers will not revert back to the original state until the voltage is switched.

The oxygen ions are guided by a series of three platinum electrodes.

This is actually very similar to how a battery charges and discharges, except that this process optimizes the structure retention of information instead of chemical energy.

Källa: Cell Device

The information states can be stored above 1100 °F for more than 24 hours.

Endast ett första steg

This scientific publication was really a proof of concept more than anything else. The initial device only retains one bit of information, but there is no theoretical limit to a much larger memory capacity.

“Hittills har vi byggt en enhet som lagrar en bit, på samma nivå som andra demonstrationer av högtemperaturdatorminnen. Med mer utveckling och investeringar skulle den teoretiskt kunna lagra megabyte eller gigabyte data.”

Yiyang Li – U-M adjungerad professor i materialvetenskap och teknik

In itself, this technology is relatively similar in its performance to other materials that have been developed for re-writable, high-temperature memory (like ferroelectric memory and polycrystalline platinum electrode nanogaps).

It has, however quite a few unique advantage,s making it more likely to be worth improving:

• Den kan fungera vid lägre spänningar än vissa av de ledande alternativen.
• Den kan erbjuda fler analoga tillstånd för beräkning i minnet.
  • Finare kontroll av syregradienten kan möjliggöra beräkning i minnet, med mer än 100 resistansnivåer istället för ett enkelt binärt.
• Beräkning i minnet kan bli möjlig, vilket tillåter enkla beräkningar att utföras av minnet utan att lägga till en klassisk kiselbaserad krets.

AI vid hög temperatur?

Such analog capacity with complex data encoding instead of the simpler 0 & 1 of binary could help drastically reduce power consumption.

This could be a game changer for using anything close to AI technology in high-temperature environments. Conventional computing would be too power consuming, itself a source of heat that is sometimes difficult to deal with in normal conditions. Doing so in 500-600°C conditions is nearly impossible.

“Det finns stort intresse för att använda AI för att förbättra övervakning i dessa extrema miljöer, men de kräver kraftfulla processorchips som förbrukar mycket energi, och många av dessa extrema miljöer har också strikta energibudgetar.

In‑memory‑computing‑chips kan hjälpa till att bearbeta en del av datan innan den når AI‑chipsen och minska enhetens totala energiförbrukning.”

Alec Talin – Seniorforskare i avdelningen för kemi, förbränning och materialvetenskap vid Sandia National Laboratories

Begränsningar

One major limitation of this technology is that it only works at high temperatures. New information can only be written on the device above 500°F (250°C).

So, if the memory needs to be used in both high and low temperatures, this could be a serious issue. And while the researchers suggest a heater could solve the problem for devices that must also work at lower temperatures, this is likely not ideal.

Tillämpningar

This sort of high-temperature memory and electronic systems would be ideal for measuring data and doing computation in extreme environments.

For example:

• Rymdteknik: I jetmotorer, där interna temperaturer kan vara extremt höga, kan denna minnesteknik möjliggöra omborddatainsamling och realtidsövervakningssystem som fungerar pålitligt utan behov av omfattande kylsystem.
• Energisektor: Geotermisk energiextraktion innebär utrustning som utsätts för höga underjordiska temperaturer. Implementering av detta värmebeständiga minne kan förbättra hållbarheten och effektiviteten hos nedgrävda övervakningsinstrument, vilket leder till mer effektiv resursförvaltning.
• Industriell tillverkning: Processer som metallsmide och glasproduktion sker vid förhöjda temperaturer. Integration av denna minnesteknik i styrsystem kan förbättra processtyrning och automatisering, minska driftstopp och underhållskostnader.
• Rymdforskning: På planeter med extrema yttemperaturer, som Venus, misslyckas traditionell elektronik. Detta framsteg kan underlätta utvecklingen av sonder och rovers som kan genomföra längre uppdrag i sådana hårda förhållanden, vilket utökar våra utforskningsmöjligheter.
• Kärnkraft: Komponenter utsätts för intensiv värme och strålning. Användning av detta robusta minne kan förbättra motståndskraften och livslängden hos reaktorövervakningssystem, vilket bidrar till säkrare och mer effektiv energiproduktion.

Tantalum Electronic Company

Vishay Intertechnology

As tantalum-based electronics are finding new applications for high-temperature conditions in advanced technology like aerospace and geothermal energy, current leaders in the segment might benefit in the long term.

Tantal används för närvarande mest för kondensatorer, allowing for a very thin dielectric layer and providing high capacitance values in smaller case sizes.

Vishay offers surface mount and through-hole tantalum capacitors for use in automotive, military, portable consumer devices, medical devices, and many other applications.

Källa: Vishay

The company also produces power electronics (silicon carbide) and other electronic components: diodes, MOSFET (metal-oxide-semiconductor field-effect transistor), optoelectronics sensors, resistors, magnets, and other types of capacitors.

The largest categories are by revenues: resistors, MOSFETs, and diodes.

This gives Vishay the “world’s largest portfolio of discrete semiconductors and passive components”.

Källa: Vishay

Most of the company’s sales come from Asia (39%) and Europe (35%), with manufacturing facilities in North America, Asia, and Europe.

The company’s expertise in producing electronics made of electronic material will be an asset as the industry is expanding beyond silicon chips and new materials.

The company is currently undergoing a restructuring program, closing 3 facilities by the end of 2026 and reducing headcount by 6%, in order to save $23M annualized. At the same time, it is expanding production where needed, with a $2.6B investment in capacity expansion over the next 4 years. This should be compared to a revenue of $720M in Q3 2024, and a policy of returning to shareholders around $100M.

Overall, Vishay’s manufacturing expertise in complex electronic components in power and semiconductor applications, using exotic metals like tantalum, should come in handy in growing its sales from the development of renewables, 5G telecoms, EVs, and aerospace.

Studierreferens:

^{1. Li, J., et al. (2024). Icke-flyktigt elektrokemiskt minne vid 600°C möjliggjort av fasseparering av sammansättning. Device. https://doi.org/10.1016/j.device.2024.100623}