Have you sat through a Marvel Avenger movie and thought, how on Earth is Iron Man able to create a suit of armor that seemingly rebuilds and reshapes itself from nothing? I mean, it’s quite impressive, but how is it even possible?

Well, it’s because of nanotechnology. It’s a term you’ve probably heard of, but not many people know what it means.

Nanotechnology is used to create many things we use and see in our daily lives, and you might not even realize it. It’s used in all our electronic devices, the vehicles we drive, and even the cosmetics we put onto our skin.  

Although there isn’t an Iron Man-like suit available yet, we could see something like it built in the near future, and it’s all possible due to nanometers – the measurement of particles on a nanoscopic scale. But what is a nanometer?

That’s precisely what this article will explore. We’ll take a holistic view of a nanometer, how it is measured, what it can be used for, how it relates to nanotechnology, and much more.

A nanometer is a unit of length that is equal to one billionth of a meter. It has the symbol nm and is part of the metric system, also known as the International System of Units (SI).

Nanometers are typically used to measure tiny things that are not visible to the human eye, such as high-frequency wavelengths, atoms, and molecules. There’s a whole industrial field behind the use of nanometers called Nanotechnology, and it even has its own measurement scale called the nanometer scale – sometimes referred to as the nanoscopic scale.

How big is a nanometer?

A single nanometer is so small that it is invisible to the human eye and can only be viewed using specialized microscopes. For most people, it’s hard even to comprehend how small a nanometer is. Here is how one nanometer compares to other small objects:

  • One DNA molecule is around 2nm thick
  • One bacteria cell is between 1,000 and 2,000 nm thick
  • One strand of human hair is between 40,000 and 100,000 nm thick
  • One sheet of paper is between 75,000 and 100,000 nm thick
  • The head of a pin is 1,000,000 nm thick
  • Your fingernail grows at an approximate length of 1 nm per second
  • If the size of the Earth represented one meter, a single tennis ball would be the equivalent of one nanometer

As you can see from these examples, it's incredibly difficult for the human brain to fathom the size of one nanometer. In fact, it's hard for the brain to imagine one billion or one billionths of anything – the difference in scale is too large. 

For instance, suppose you were converting seconds to days and years. One million seconds equates to roughly 11.5 days. However, one billion seconds equates to 11,574 days, resulting in a staggering 31 and a half years – crazy, right? The difference between one to one million is an already hard concept to imagine. But the difference between one million and one billion is staggering, let alone conceptualizing one to one billion.

Another example is if you had a savings goal of one billion dollars ($1,000,000,000) and were putting away $100 each day towards it. It would take you a whopping 27,397.26 years to achieve that goal, which is over 300 lifetimes. 

This works the other way as well when you’re scaling down from one to one billionth, as is the case with going from one meter to one nanometer – in fact, and it’s probably even harder to imagine. But, the examples shown above can hopefully give you an idea of the minute scale of nanometers. 

What is a nanometer used to measure?

Nanometers are used to measure objects on an atomic scale, such as atoms, biological cells, and wavelengths of light and radiation. For instance, a helium atom is measured to have a diameter of around 0.06 nm, and the wavelength of visible light ranges from 375 to 725 nm in length. Nanometers are also used in nanotechnology, which has applications in electronics, biology, medicine, and engineering – more on that later.

How are nanometers measured?

Nanometers are typically measured using specialized microscopes, such as an atomic force microscope (AFM), scanning electron microscope (SEM), transmission electron microscope (TEM), or optical microscope. 

In truth, various measurement methods have been developed that use slightly different techniques. As such, they all have pros and cons, and the best instrument for the job will depend on the object you’re trying to measure, how detailed an image you need, and what information you’re looking to extract.

For instance, an atomic force microscope has an incredibly fine needle-like tip that runs over the surface of a particle or material like a stylus. Essentially, it feels the shape of the surface and its atoms which a computer then uses to create an image. The advantage of an AFM is that it creates a high-contrast 3D image that helps you see the physical properties of an object.

On the other hand, a scanning electron microscope fires a beam of electrons onto the surface. As the electrons bounce back, the information is detected to create an image of the object’s surface and structure. As opposed to an AFM, an SEM only provides a 2D image. But, it has a high depth of field and is great for understanding the chemical composition of a particle or material.

A specialized optical microscope uses light and works similarly to the optical microscopes you’d see in a lab or school classroom. Light microscopes have the benefit of not having to prepare the object you measure in a vacuum as you would with the previous two microscopes. But, the trade-off is that you sacrifice the image quality, which is not as accurate as an AFM or SEM.

There’s a whole subfield in metrology – the science of measuring – dedicated to measuring nanometers called ‘nanometrology’. The technological advances in nanometrology led to the development of these measurement instruments mentioned above, and the greater our ability to measure nanometers as accurately as possible, the greater our ability to understand and manipulate particles and atoms on a nanoscopic scale. That’s why it forms the backbone of nanotechnology.

What are the uses of nanometers?

When we talk about the use of nanometers, we typically refer to objects and things that can be measured on a nanoscopic scale – i.e., individual atoms and molecules. But, once we’re able to measure them on such a scale, we’re also able to manipulate them and measure changes, and that’s exactly what the field of nanotechnology is.

Nanotechnology, as a science, has uses cases in a vast array of fields such as engineering, medicine, biology, electronics, and more. Let’s explore them in more detail.

Material Science and Engineering

Every year, billions of dollars go into researching and developing new materials. The goal is to alter the structure of materials on a molecular and atomic scale to achieve a particular property. In doing so, materials can be made stronger, more durable, lighter, more energy efficient, better conductors of electricity, etc. 

Examples include nanoscale films that are put on windows, eyeglasses, or computer displays, which can make them antimicrobial, scratch-resistant, water-repellent, anti-glare, etc. 

Or carbon nanotubes which are put on solar panels. They increase the heat and electric conductivity of the panels while being strong structurally, flexible, and low in weight, thus improving their overall energy efficiency.

Nanotechnology is also heavily used in household products to create materials and products that are better at removing stains, filtering or purifying the air, and resisting dirt or bacteria. They’re also used in skincare products such as sunscreens to protect you from UV rays better while appearing invisible to the naked eye.

Biology and Medicine

Nanotechnology is widely used in biology and medicine for a variety of purposes. For instance, new tools for the diagnosis and early treatment of diseases and infections are constantly being tested and developed. One example of how this is done is by detecting certain proteins in the blood, which can show early signs of cancerous or malignant cells. 

Nanotechnology is also used in genetic engineering. Scientists can enhance or eliminate certain characteristics by making changes to the individual genes in a deoxyribonucleic acid (DNA) molecule. This is particularly relevant for plants where these changes can help improve disease resistance, growth, and reproduction efficiency.

Tying into the previous point, nanotechnology is heavily used in agriculture. Examples include creating pesticides and fertilizers that improve the crop’s yield while minimizing toxicity to humans, detecting pathogens and toxins in soils, and improving the health and productivity of livestock.

Information Technology and Electronics

We’ve mentioned the use of nanotechnology in engineering, material science, and medicine. Still, it could be argued that the field where it’s had the most impact is electronics and information technology (IT). 

The use of nanoparticles in microchips, transistors, capacitors, displays, etc., has allowed electronics to become progressively faster, more portable, and more efficient. For instance, you can buy a high-resolution flat-screen TV where the colors seem to 'pop' because certain nanoparticles have been altered to absorb particular wavelengths. This results in the colors seeming more vibrant and 'real'.

Another example is the microchip. As nanotechnology is used to create smaller and smaller transistors, this has resulted in more transistors being able to fit on a single microchip, thus increasing performance. A great illustration of this is the creation of the Apple M1 chip, which took the computing world by storm in 2020. Apple was able to fit 16 billion transistors onto its small chip, which was more than all its competitors, thus producing extremely small machines by size but powerful in performance. 

These are but a few examples of how nanometers and nanotechnology are used in our daily lives. Some of the greatest medicinal, engineering, and information technology innovations we’ve come to appreciate are due to changes made on a nanoscopic scale.

History of nanometer

The term ‘nanometer’ was first introduced in 1960. Still, the measurement scale for what we now refer to as a nanometer has existed for many years. Before 1960, it was known as the millimicrometer – shortened to millimicron – and had the symbol 

It combined two prefixes, ‘milli–’ and ‘micro-’. Milli- refers to one thousandth, and micro- refers to one millionth. Therefore, one micrometer – or one micron – equated to one-millionth of a meter, and millimicron meant one-thousandth of a micron, which equated to one-billionth of a meter. 

However, in 1960, the General Conference on Weights and Measures (GCPM) approved the plan to standardize the metric system globally. This was done by creating the International System of Units (SI), which – among many other things – consisted of a revamp of certain prefixes. 

Describing one billionth of a unit as millimicro- was considered too long and confusing and was thus replaced by a new prefix, nano-. ‘Nano’ is derived from the Greek word ‘nanos’, which translates to “dwarf”. Much like its predecessor, the nano- prefix can be added to any base unit, including a meter. 

Summary

Nanometers are metric units of measurement that are used to measure objects or particles that are invisible to the human eye. Examples include atoms, molecules, and wavelengths of light. 

Specialized microscopes are used to measure objects on such a small scale. They can then be used to manipulate them and record the changes. This is called nanotechnology, and it has applications in various fields, such as medicine, IT, engineering, and biology.