We are constantly inspired by nature’s remarkable design and engineering capabilities when it comes to our work. That’s why we strive to create pieces that elegantly capture the sense of wonder that arises through our connection with nature.

EUV lithography brings many advantages that could lead to future developments in microchip production. Here are two of the reasons why semiconductor companies like Intel are investing so much in the technology:

Light on prismformula

The generated light is gathered and directed through a series of mirrors and optics through a mask or reticle as a circuit pattern is placed in the path of the EUV light, in a manner loosely analogous to using a stencil to paint a pattern on a board. A material called photoresist on the wafer is sensitive to EUV light, and the areas exposed to it go through a chemical change and are then etched. New materials may then be deposited in the etched areas to form the various components of the microchip. This process can be repeated up to 100 times with different masks to create multilayered, complex circuits on a single wafer.

Moreover, for each wavelength of light, there’s a different degree of refraction. The two elements are inversely proportional: the shorter the wavelength of light, the higher the amount of refraction.

EUV light is used in microchip lithography to produce the patterns necessary to create a microchip, though at far smaller sizes than from previous lithographic techniques. However, because of its novelty, only one company—ASML—makes machines that use it, and they are costly. As the technology matures, it should play a central role in future developments in microchip production.

Extreme ultraviolet light is used in the production of microchips. EUV lithography prints a pattern on silicon wafers during the manufacturing process.

Newton determined through a series of experiments involving a triangular glass prism that white light is the sum of the seven colors of the visible spectrum—red, orange, yellow, green, blue, indigo and violet. His discovery replaced Aristotle’s theory of color, which suggested that all the colors result from the combination of white and black.

Every few years since then, ASML has delivered the next iteration of its EUV lithography systems with more capacity for production and wavelengths down to 13.5 nanometers. This allows for incredibly precise microchip designs and the densest possible placement of transistors on microchips—in short, it enables faster computer speeds.

Dispersion oflightthroughprism

While we did touch upon the subject of prisms when we talked about how a diamond’s cut influences its optical properties, in this blog, we’re going to present a more in-depth approach to how prisms interact with light.

Glasslight on prism

In the eastern culture, double rainbows are considered a symbol of transformation and growth, bringing good fortune to the observers. Also, the primary rainbow is often associated with the material world, while the secondary arc represents the spiritual world.

As we explained in the previous section, since the violet light is refracted most, it emerges on top. Also, the red light is refracted less, which means we can observe it at the top of the rainbow.

Refraction oflightthrough aprism

Brian Cardineau et al., via ScienceDirect. “Photolithographic Properties of Tin-Oxo Clusters Using Extreme Ultraviolet Light (13.5 nm).” Microelectronic Engineering, Vol. 127, September 2014, Pages 44–50.

During this process, white light is dispersed into the visible spectrum, the most intensity of light being found between 40° and 42°. Depending on the index of refraction of water for each wavelength, a different color will reach back to our eyes.

Another thing worth mentioning is that, in theory, all rainbows are full circles. However, from Earth, we can only see the rainbow as a semicircle, as our eyes can perceive only the wavelengths of light reflected above the horizon. The only way to see rainbows as a whole circle is from an airplane.

While major purchases of EUV lithography systems have been driving news in the superconductor industry, given the dramatic costs involved and the technological advances it could bring, DUV lithography is still more widely used. It has the advantage of already being in manufacturing facilities with staff trained in its use.

EUV lithography, with its extremely short wavelengths of about 13.5 nanometers, allows for finer etching of smaller features on chips. For its part, DUV lithography operates at wavelengths starting at 153 nanometers. While chipmakers can use this for designs with sizes as small as 5 nanometers or less, pushing the boundaries of physics, DUV light can only be used for sub-10-nanometer sizes with a loss in resolution quality.

Technology is frequently improving, and the demand for microchips with increasingly dense transistors continues. While EUV lithography is at the limits of the technology, research into technology that could improve upon or replace it continues. Multi-e-beam, X-ray lithography, nanoimprint lithography, and quantum lithography could all overtake EUV lithography in the future.

The history of computers is the history of the semiconductor industry, which in turn is the history of the relentless pursuit of miniaturization. In the sector’s initial phase from the 1950s to mid-’80s, photolithography was done through UV light and photomasks to project circuit patterns onto silicon wafers.

The industry is likely in a transition, and while EUV light will play an increasingly more central role in chip manufacturing, DUV lithography is still vital to the production of electronics used in our everyday lives.

Light on prismexperiment

A perfectly cut diamond has the optical qualities of a prism. Thus, the light entering the diamond and getting refracted and dispersed contributes to the vibrant flashes of color we see when tilting the gemstone.

EUV lithography systems not only come with the startup costs of newer technologies but also are inherently more expensive than the equipment and maintenance for DUV lithography. For example, EUV lithography systems installed by Intel in 2023 cost $150 million each. This cost makes DUV lithography systems preferred for uses where EUV lithography’s smaller size is unnecessary.

Many expect DUV lithography to remain popular for years to come. This is in part because of the price of EUV lithography and the technical issues that come with any new technology. In addition, DUV lithograph technology is not stuck in place, continuing to improve how it helps create the chips found in the many electronic devices of our everyday lives.

In essence, a prism breaks the light that enters it into the colors of the spectrum due to a combination of optical phenomena: refraction and dispersion. This special characteristic of prisms was documented by physicist Sir Isaac Newton in the 17th century.

Generally, the dispersion of white light is highly accentuated when it exits the prism and a second refraction occurs. That’s why we can clearly see the rainbow reflected on the other side of the prism.

Light on prismequation

Compared to how structural colors are formed in the wings of the Morpho butterfly, prisms create color through the interplay of optical phenomena.

Simply put, refraction happens because the air has a different index of refraction than glass, meaning that light travels faster in the air than inside a glass prism since it’s a less dense medium.

EUV light refers to the extreme ultraviolet light used for microchip lithography, which involves coating the microchip wafer in a photosensitive material and carefully exposing it to light. This prints a pattern onto the wafer, which is used for further steps in the microchip design process.

However, the diamond is just one example of natural prisms. The captivating appearance of a rainbow is also the effect of color dispersion. In this case, the suspended raindrops in the air start behaving like miniature liquid prisms.

ASML’s EUV lithography systems emit light with wavelengths of about 13.5 nanometers, which is significantly shorter than the wavelengths used in the previous generation of DUV lithography, thus enabling finer patterns to be printed on semiconductor wafers​. The most advanced microchips can have nodes as small as 7, 5, and 3 nanometers, which are made by repeatedly passing the semiconductor wafers through the EUV lithography system.

When light travels from one transparent medium to another—from air to the glass of a prism, for example—it causes the ray of light to slow down and bend, changing its propagation direction. This phenomenon is called refraction.

Moore’s Law says that the number of transistors on a microchip doubles about every two years. This means that computers get faster and more capable every two years, with that growth being exponential. The law is named after Gordon E. Moore, a co-founder of Intel. Though it held true for many years, some predict it will end in the 2020s.

Dispersion of whitelightby a glassprism

Newton’s findings were published in his work Optiks and represent an important milestone in the study of color in nature.

Though you won’t be able to follow these steps in your garage workshop to make semiconductors, they are important for understanding how the technology involved can be advanced and where potential investment funds might be best placed. First, a high-intensity laser is directed at a material (usually tin) to generate plasma (charged electrons and protons in motion). The plasma then emits the EUV light at a wavelength of about 13.5 nanometers.

During this time, Moore’s Law—the 1960s dictum that the number of transistors on a microchip would double every two years—started coming up against the physical limits of this process. This meant that the staggering increases in computing power and reduced technology costs for consumers were also in danger of hitting a limit. From the 1980s to the 2000s, deep ultraviolet (DUV) lithography drove the next generation of miniaturization, using shorter wavelengths in the range of 153 to 248 nanometers, which allowed for smaller imprints on the silicon wafers of semiconductors.

Harry J. Levinson, via IOPscience. “High-NA EUV Lithography: Current Status and Outlook for the Future.” Japanese Journal of Applied Physics, Vol. 61, No. SD, April 2022.

In leading up to the new millennium, researchers and competing firms worldwide looked for breakthroughs in making EUV lithography and its even shorter wavelengths possible. ASML completed a prototype in 2003, though it would take another decade to develop a system ready for production.

After these steps, the wafer undergoes further processes to remove impurities and get the chip ready to be sliced into individual chips. They are then packaged for use in electronic devices.

Extreme ultraviolet (EUV) light technology is a key driver of change in the semiconductor industry. Lithography, the method used for printing intricate patterns onto semiconductor materials, has advanced by using ever shorter wavelengths since the beginning of the semiconductor age. EUV lithography is the shortest yet.

What does aprismdo tolight

Sometimes, we might be able to spot a secondary rainbow in the sky. A double rainbow forms as the result of light reflecting twice within the raindrops. This type of rainbow appears at about 10° on the outer side of the primary rainbow, representing the reflection of the primary arc. That’s why its color order is reversed.

Christopher K. Ober et al., via ScienceDirect. “Recent Developments in Photoresists for Extreme-Ultraviolet Lithography.” Polymer, Vol. 280, July 2023.

In development for decades, the first EUV lithography machine bought in batches and ready for production was from ASML, the Dutch semiconductor company.

When a beam of light hits the spherical surface of a water droplet, it first refracts as it enters the droplet. After the light reflects off the back of the raindrop, it undergoes refraction again as it exists.

TJ Porter is a freelance writer with eight years of experience covering finance topics ranging from credit and real estate to stocks, options, ETFs, and mutual funds. His work appears on dozens of well-known finance sites, including Credit Karma.

To properly understand how a prism refracts and disperses white light forming the visible spectrum, it’s essential to briefly explain light’s dual nature.

This article is part of our Connect with Nature blog series, where we explore how colors are created in the natural world while focusing on the relationship between light and color.

After light enters the prism and gets refracted, it’s split into its component wavelengths or colors. This phenomenon is known as dispersion. The reason why chromatic dispersion happens is that the refractive index of the medium varies for each wavelength, thus making them bend at different angles.

Therefore, short wavelengths such as violet and blue are slowed down more and undergo more bending than longer wavelengths like red and orange.

In simple terms, light is made of particles (photons) with various wavelengths and frequencies. Short wavelengths have a high frequency (energy) and move faster, while longer wavelengths have a lower frequency and travel more slowly.

DUV lithography is also a known quantity: There is no need for additional training, new facilities, and other major capital investments that EUV light systems require. DUV light technology is still needed for many chips in phones, computers, cars, and robots, and it has proved robust and versatile. Its relatively simpler processes also mean that DUV lithography can produce more chips per unit of time than EUV lithography, an important point in its favor in light of the global demand for semiconductors.