Nanometers: what they are and how they affect our cpu

Have you ever heard of a processor's nanometers ? Well, in this article we are going to tell you all about this measure. And most importantly, what influence do nanometers have on electronic chips and the different elements that we refer to with these measurements.

What is the nanometer

Let's start precisely by defining what nanometers are, because this simple fact will give a lot of play not only for computing, but also in biology and the other sciences that matter studies.

The nanometer (nm) is a measure of length that is part of the International System (SI). If we consider that the meter is the standard or basic unit on the scale, a nanometer is one billionth of a meter or what would be the same:

In terms understandable to a normal human being, something that measures a nanometer, we can only see it through a high-powered electron microscope. For example, a human hair can have a diameter of approximately 80, 000 nanometers, so imagine how small an electronic component is that is only 14 nm.

This measure has always existed, it is obvious, but for the hardware community it has had a special relevance in recent years. Due to the strong competition of manufacturers to create integrated circuits based on increasingly smaller semiconductors or transistors.

The transistor

Transistor and electronic schematic

You have probably heard passive and active talk about the transistors of a processor. We can say that a transistor is the smallest element that can be found in an electronic circuit, of course, avoiding electrons and electrical energy.

Transistors are elements made of semiconductor material such as Silicon or Germanium. It is an element that can behave as a conductor of electricity or as an insulator thereof, depending on the physical conditions to which it is subjected. For example, a magnetic field, temperature, radiation, etc. And of course with a certain voltage, being the case of the transistors of a CPU.

The transistor is present in absolutely all the integrated circuits that exist today. Its enormous importance lies in what it is able to do: generate an output signal in response to an input signal, that is, allow or not the passage of current before a stimulus, thus creating the binary code (1 current, 0 not current).

Logic gates and integrated circuits

NAND ports

Through a lithography process , it is possible to create circuits with a certain structure made up of several transistors to form the logic gates. A logic gate is the next unit behind the transistor, an electronic device that is capable of performing a certain logical or boolean function. With a few transistors linked in one way or another, we can add, subtract, and create SI, AND, NAND, OR, NOT, etc gates. This is how logic is given to an electronic component.

This is how integrated circuits are created, with a succession of transistors, resistors and capacitors that are capable of forming what are now called electronic chips.

Lithography or photolithography

Silicon wafer

Lithography is the way to build these extremely small electronic chips, specifically it has derived in the name of photolithography and then nanolithography, since this technique in its beginnings was used to engrave content on stones or metals.

What is currently being done is using a similar technique to create semiconductors and integrated circuits. To do this, nanometer-thick silicon wafers are used which, through processes based on the exposure to light of certain components and the use of other chemical compounds, are capable of creating circuits of microscopic sizes. In turn, these wafers are stacked until they get a hell of a complex 3D chip.

How many nanometers do current transistors have?

The first semiconductor-based processors appeared in 1971 by Intel with its innovative 4004. The manufacturer managed to create 10, 000 nm transistors, or 10 micrometers, thus having up to 2, 300 transistors on a chip.

Thus began the race for supremacy in microtechnology, currently renowned for nanotechnology. In 2019, we have electronic chips with a 14nm manufacturing process that came with Intel's Broadwel architecture, 7nm, with AMD's Zen 2 architecture, and even 5nm tests are being carried out by IBM and other manufacturers. For us to put ourselves in a situation, a 5nm transistor would be only 50 times larger than the electron cloud of an atom. A few years ago, it was already possible to create a 1 nm transistor, although it is a purely experimental process.

Do you think that all manufacturers make their own chips? Well, the truth is that no, and in the world, we can find four great powers that are dedicated to the manufacture of electronic chips.

• TSMC: This micro-technology company is one of the world's leading chip assemblers. In fact, it makes the processors from brands like AMD (the core part), Apple, Qualcomm, Nvidia, Huawei or Texas Instrument. It is the key manufacturer in 7nm transistors. Global Foundries - That's another of the silicon wafer manufacturers with the most customers, including AMD, Qualcomm, and others. But in this case with 12 and 14 nm transistors among others. Intel: The blue giant has its own processor factory, so it does not depend on other manufacturers to create its products. Perhaps this is why the 10nm architecture is taking so long to develop against its 7nm competitors. But rest assured that these CPUs will be brutal. Samsung: The Korean company also has its own silicon factory, so we are on the same terms as Intel. Creating your own processors for smartphone and other devices.

Moore's law and the physical limit

Graphene transistor

The famous Moore's Law tells us that every two years the number of electrons in microprocessors doubles, and the truth is that this has been true since the beginning of semiconductors. Currently, chis are sold with 7nm transistors, specifically AMD has processors in this lithography for desktops, the AMD Ryzen 3000 with the Zen 2 architecture. Similarly, manufacturers such as Qualcomm, Samsung or Apple, also have 7nm processors for mobile devices.

The 5 nm nanometer is set as the physical limit to make a Silicon based transistor. We must know that the elements are made up of atoms, and these have a certain size. The world's smallest experimental transistors measure 1nm, and are made of graphene, a material based on much smaller carbon atoms than silicon.

Intel Tick-Tock Model

Intel Tick Tock Model

This is the model that the manufacturer Intel has adopted since 2007 to create and evolve the architecture of its processors. This model is divided into two steps which is based on reducing the manufacturing process, and then optimizing the architecture.

The Tick step occurs when the manufacturing process decreases, for example from 22nm to 14nm. While the Tock step what it does is maintain that same manufacturing process and optimize it in the next iteration instead of further decreasing the nanometers. For example, the 2011 Sandy Bridge architecture was the Tock (an improvement from Nehalem's 32nm), while the Ivy Bridge was the Tick in 2012 (decreased to 22nm).

A priori, this plan what he intended was to make a year Tick and he continues Tock, but we already know that the blue giant has abandoned this strategy from 2013 with the continuation of 22 nm in Haswell and the move to 14 nm in 2014. Since then, the whole step has been Tock, that is, the 14 nm have continued to be optimized until reaching the 9th generation Intel Core in 2019. It is expected that this same year or early 2020 there will be a new Tick step with the arrival of 10 nm.

The next step: the quantum computer?

Possibly the answer to the limitations of semiconductor-based architecture lies in quantum computing. This paradigm completely changes the philosophy of computing from the beginning of computers, always based on the Turing machine.

A quantum computer would not be based on transistors, nor on bits. They would become molecules and particles and Qbits (quantum bits). This technology tries to control the state and the relationships of the molecules in the matter by means of electrons to obtain an operation similar to that of a transistor. Of course, 1 Qbit is not equal to 1 bit at all, since these molecules can create not two, but three or more different states, thus multiplying the complexity, but also the ability to perform operations.

But for all this we have some small limitations, such as needing temperatures close to absolute zero (-273 ^o C) to control the state of the particles, or having the system mounted under vacuum.

• For more information on all this, visit this article that we studied a while ago about what is the quantum processor.

What do nanometers influence processors?

We leave behind this exciting and complex world of electronics in which only manufacturers and their engineers really know what they are doing. Now we will see what benefits it has to decrease the nanometers of a transistor for an electronic chip.

5nm transistors

Higher transistor density

The key is transistors, they determine the number of logical ports and circuits that can be put inside a silicon of only a few square millimeters. We are talking about almost 3 billion transistors in a 174 mm ² matrix such as the 14nm Intel i9-9900K. In the case of the AMD Ryzen 3000, about 3.9 billion transistors in a 74mm ² array with 7nm.

Higher speed

What this does is provide the chip with much more processing power, since it is capable of locking with many more states on a chip with a higher density of semiconductors. In this way, more instructions per cycle are achieved, or what is the same, we raise the processor's IPC, as for example if we compare the Zen + and Zen 2 processors. In fact, AMD claims that its new CPUs have increased their Core CPI up to 15% compared to the previous generation.

Greater energy efficiency

By having transistors with fewer nanometers, the amount of electrons that pass through them is less. Consequently, the transistor changes state with a lower power supply, so this greatly improves energy efficiency. So let's say we can do the same job with less power, so we're generating more processing power per watt consumed.

This is very important for battery-powered equipment, such as laptops, Smartphone, etc. The advantage of having 7nm processors, has made us have phones with incredible autonomies, and spectacular performance with the new Snapdragon 855, the new A13 Bionic from Apple and the Kirin 990 from Huawei.

Smaller and fresher chips

Last but not least, we have the miniaturization capability. In the same way that we can put more transistors per unit area, we can also decrease this to have smaller chips that generate less heat. We call this TDP, and it is the heat that a silicon can generate with its maximum charge, beware, it is not the electrical power it consumes. Thanks to this, we can make devices smaller and that heat up much less having the same processing power.

There are also disadvantages

Every big step forward has its risks, and the same can be said in nanotechnology. Having transistors of less nanometers, makes the manufacturing process much more difficult to perform. We need much more advanced or expensive technical means, and the number of failures increases substantially. A clear example is that the performance per wafer of correct chips has decreased in the new Ryzen 3000. While in Zen + 12 nm we had around 80% of perfectly functional chips per wafer, in Zen 2 this percentage would have decreased to 70%.

Similarly, the integrity of the processors is also compromised, thus requiring more stable power systems, and with better signal quality. That is why the manufacturers in the new AMD X570 chipset boards have taken special care in creating a quality VRM.

Conclusions about nanometers

As we see, the technology is advancing by leaps and bounds, although in a few years we will find manufacturing processes that will already be at the physical limit of the materials used with transistors of even 3 or 1 nanometers. What will be next? Well we certainly don't know, because quantum technology is very green and it is practically impossible to build such a computer outside of a laboratory environment.

What we will have for now is to see if in such a case the number of cores is increased even more, or materials such as graphene that admit a higher density of transistors for electronic circuits are started.

Without further ado, we leave you with other interesting articles:

Do you think we'll get to see 1nm processors? What processor do you have? We hope the article was interesting, tell us what you think.