A nanometre essentially means a small unit of measurement. An extremely small unit of measurement. If you take one strand of your hair and divide its width into eighty thousand equal slices, each one of those slices is roughly one nanometre. A nanometre is such a small measurement that you can’t see it with the naked eye. And when things get that tiny, the rules of behaviour – physical and chemical – change. Enabling innovation at the nanometre scale allows for the fine-tuning of material properties. This is one of the reasons nanometre technology underpins some of the most consequential innovations being built today across electronics, medicine, energy, defence, construction, and manufacturing.
What is a nanometre?
A nanometre (nm) is one billionth of a metre, or 10⁻⁹ m. But how does that translate into something tangible? A few examples are:
- A human hair is approximately 80,000-100,000nm wide
- A sheet of standard office paper is roughly 100,000nm thick
- A single atom is typically 0.1-0.3nm across
The nanoscale is defined as the range from one to 100 nanometres, though in practice engineers and materials scientists work with structures up to a few hundred nanometres where the properties of the nanoscale still apply.
Why scale changes everything
Changing a material’s geometry changes its performance. If you make a beam thinner, it bends more easily. Add surface area to a heat exchanger, and it transfers heat faster. At the nanoscale, the outcomes aren’t changed, exactly, but the effects are notable and operate through such different mechanisms that the resulting materials can feel like entirely new substances.
There are two main reasons for this.
Surface area expansion
When you break a bulk material down into nanoscale particles, the ratio of surface area to volume increases enormously. The US National Nanotechnology Initiative explains it like this: a solid cube of material one centimetre on each side has about six square centimetres of surface area. Break the same amount of material into particles 10 nanometres in diameter, and the total surface area approaches the size of a football pitch.
Chemistry, whether that’s reactivity, catalysis, bonding, or dissolution, happens at the surface level, and so a nanoparticle has a much higher proportion of its atoms sitting on or near its surface than a bulk particle of the same material – making it much more reactive. This is why nanoscale gold particles are highly chemically active, despite bulk gold being inert.
Quantum effects kick in
Below around 100nm, quantum mechanical effects start to dominate material behaviour. Electrons in a bulk material use quasi-continuous bands of energy. But if you confine them to a nanoscale space, the bands break into discrete energy levels. This is what’s known as quantum confinement, and it means a material’s electronic, optical, and magnetic properties become dependent on its size and shape rather than just its chemical composition.
To use a visual cue for this, if we look at gold. Bulk gold is gold-coloured. But if it is reduced to nanoparticles of around 20nm, it appears deep red or purple. Reduce it further, and it changes to orange. The particles are made of the same atoms – only their size has changed. This effect is caused by how the nanoparticles interact with light through localised surface plasmon resonance, and it underpins everything from cancer diagnostics to the colour in some stained glass windows.
The surface area effect and quantum confinement explain why nanotechnology is not just about making things smaller. It is about accessing a fundamentally different set of material properties.
Where did it come from?
The intellectual origin of nanotechnology is usually traced to a lecture given by the physicist Richard Feynman in 1959, called ‘There’s Plenty of Room at the Bottom.’ Delivered to the American Physical Society at Caltech, it explored the theoretical possibility of manipulating matter at the atomic scale.
However, the lecture had less impact at the time than its later reputation suggests. Nature Nanotechnology noted in a 2009 retrospective that it was cited just seven times in the two decades after it was first published, and that many scientists active in the early development of the field did not consider it a direct influence on their work.
Advances in instrumentation drove the field forward.
The invention of the scanning tunnelling microscope (STM) in 1981 by Gerd Binnig and Heinrich Rohrer at IBM Zurich gave researchers a tool that could, for the first time, resolve and interact with individual atoms.
The term nanotechnology, as we use it today, was popularised by Eric Drexler in his 1986 book ‘Engines of Creation’, though the word itself was coined by the Japanese engineer Norio Taniguchi in 1974 in reference to thin-film manufacturing processes.
The US government formalised the field’s importance in 2000 with the establishment of the National Nanotechnology Initiative (NNI), which has since directed almost $47 billion in federal investment towards nanotechnology research.
Working at the nanoscale
Working at the nanoscale requires both new ways of building and new ways of seeing.
Building
There are two basic approaches to nanofabrication: top-down and bottom-up.
Top-down starts with a bulk material and removes or shapes it down to nanoscale precision. Semiconductor manufacturing is the canonical example: chip makers use photolithography (and now extreme ultraviolet, or EUV, lithography) to etch features a few nanometres wide into silicon wafers. This approach is widely used in microelectronics.
Bottom-up works in the opposite direction, whereby structures are assembled atom by atom or molecule by molecule. Self-assembly – where molecules organise themselves into structures under the right conditions – is the most practically scalable form of this. It is how DNA nanotechnology works, and how lipid nanoparticles for drug delivery are formed.
Seeing
Visible light has a wavelength of roughly 380-700nm. This means a conventional optical microscope cannot resolve anything smaller than a few hundred nanometres, which is too coarse for nanoscale work.
The following three instrument families have defined the field because they are not just observation tools; they are engineering platforms.
- Electron microscopes: use beams of electrons, whose wavelengths are smaller than visible light, to image features down to the sub-nanometre scale
- Scanning probe microscopes: physically sense a surface using a sharp tip, building an image by measuring the forces between the tip and surface atom by atom. They can both image and manipulate matter at atomic resolution
- X-ray diffraction and scattering: these techniques probe the internal structure of nanomaterials without direct imaging
Where nanometre technology is already at work
Nanotechnology is already embedded in many of the products and systems that engineers design, specify, and maintain today.
Some examples are:
Electronics: the transistors in modern chips are measured in single-digit nanometres. TSMC and Samsung both now manufacture at 3nm nodes, with 2nm in commercial production.
Sunscreen: zinc oxide and titanium dioxide nanoparticles have been used in sunscreen formulations for years, providing effective UV absorption while staying transparent on the skin.
Medicine: the COVID-19 mRNA vaccines were administered to billions of people using lipid nanoparticles (LNPs) – engineered nanoscale capsules that protect the fragile mRNA molecule, transport it into cells, and release it intracellularly.
Stain-resistant fabrics: textiles treated with nano-silica or similar coatings create a hydrophobic surface that repels water and stains without altering the fabric’s feel. Silver nanoparticles embedded in medical and athletic fabrics inhibit bacterial growth.
Energy storage: nanostructured silicon electrodes in lithium-ion batteries deliver specific capacities more than double that of conventional graphite electrodes.
Structural composites: carbon nanotubes and graphene incorporated into polymer composites improve tensile strength, electrical conductivity, and thermal performance.
However, these applications are only what has already been established. Every day, more and more research and development are in the pipeline, in areas such as cancer therapy, renewable energy, and environmental remediation.
Nanoscale = big opportunity
The nanotechnology market is expected to steadily rise from around $85–$105 billion in 2024–2025 to around $265–$400 billion by the mid-2030s. Since its inception, the US National Nanotechnology Initiative has allocated over $45 billion to nanotechnology research.
More than 1.07 million nanotechnology patents have been granted globally between 2000 and 2025, with China alone accounting for 43% of that total.
Nanoscale challenges
As with any technology, there are ups and downs, and nanometre technology does not come without its complications.
Measuring nanoscale features at production volumes is hard, and the properties of nanomaterials are extremely sensitive to manufacturing conditions. Not only this, but they can vary from batch to batch in ways that bulk materials do not.
Standardisation bodies, including ISO and IEC, are developing measurement frameworks, but this is an ongoing engineering challenge.
The same properties that make nanoparticles useful also raise questions about their behaviour in the body and the environment. Nanoparticles inhaled or ingested may interact with biological systems in ways their bulk-scale counterparts do not.
Many nanofabrication techniques that work brilliantly in the laboratory are slow, expensive, or inconsistent at industrial scale. Bridging that gap between proof-of-concept and manufacturable product is one of the biggest engineering challenges in the field.
Conclusion
Nanometre technology isn’t just a measurement. It’s a variable that changes what materials can do. The same atoms, arranged at a different size, behave in ways bulk matter never could, and the technology is already running through the smartphone in your pocket, the vaccine in your arm, and the sunscreen on your skin.
What started as a theoretical possibility in the 1950s has become one of the most heavily invested and most competitive fields in science, with governments and industries racing to turn atomic-scale control into commercial advantage.
The field has its challenges, but they’re the usual growing pains of an engineering discipline that’s still finding its footing. And once those footholds become stable, much more of what’s possible at the nanoscale will open up.
