Hand rubbing nuclear fusion live in the wilderness

Chapter 414 Ion Doping of Carbon-Based Chips

The emergence of the theory of orbital hybridization has moved all countries.

Talents with related majors and even compulsory orbital hybrid courses such as theoretical chemistry and molecular chemistry were urgently summoned to participate in this live broadcast to learn.

This theory, which is thought to take at least ten or even twenty years to perfect, is about to be used now that no one has thought of.

However, according to normal development, there is actually no big problem with the predictions of various countries.

Han Yuan has studied the theory of orbital hybridization in depth, and he knows the amount of relevant knowledge in this course and the difficulty of learning it.

It is no exaggeration to say that if he had studied this course before he got the system, he would not even get ten points for the 100-point test paper.

Learning this thing is like learning mathematics.

It all depends on talent, if you know it, you will, if you don't, you won't.

Although this thing is the basis of organic chemistry, and even one of the basic theories of chemistry, it is actually a subject that is easy in the early stage and extremely difficult in the later stage.

And if it is only used to lay the foundation, it is not difficult to learn.

But after crossing the basics, the difficulty of what needs to be learned has increased to N levels.

Not only a mathematical foundation is required, but a physical foundation is also required.

Moreover, with the introduction of theories related to orbital hybridization, such as crystal field, ligand field, molecular orbital and frontier molecular orbital, a scholar who studies orbital hybridization technology in depth needs to learn several times more than other chemistry courses.

In the laboratory, while handling the graphene single crystal wafer in his hand, Han Yuan explained the precautions for N/P pole doping through the "orbital hybridization technology".

"Wafers made of graphene single crystal materials are similar to single crystal silicon wafers in terms of processing methods. They are all doped with corresponding ions by ion implantation to make different N/P poles, and then change the doping area. conduction in such a way that each transistor can be turned on, off, or carry data."

"Of course, when the two are doped, the ions used are different."

"When silicon-based chips are ion-doped, phosphorus and boron are common ions, and of course gallium, arsenic, aluminum and other elements are also present."

"This needs to be selected according to the different uses of the chip, and even the etched circuit diagram."

"The dopant ions used by the carbon-based chip are not the above-mentioned ones, it uses a metal ion."

Han Yuan paused, glanced at the camera to whet the appetite of the audience, and then continued:
"The dopant ions used in carbon-based chips are 'metal silver ions' and 'silicon ions'."

Silver and silicon?
The experts from various countries who were squatting and studying in the live broadcast room were taken aback after hearing Han Yuan's words, and immediately thought about it.

Both silver and silicon are very common materials here. Needless to say, silicon itself is the basic raw material for manufacturing silicon-based chips and various silicon semiconductors.

As for silver, in addition to being commonly used in various jewelry and decorations in life, its greater use is actually industry.

The physical and chemical properties of silver are quite stable, thermal conductivity and electrical conductivity are very good, the texture is quite soft, very ductile, and its reflectivity is extremely high, which can reach more than 99%, and it has many important uses.

For example, silver is commonly used to make highly sensitive physical instrument components, various automation devices, rockets, submarines, computers, nuclear devices and communication systems.

A large number of contact points in all these devices are made of silver.

During use, each contact point has to work millions of times, must be wear-resistant and reliable, and can withstand strict working requirements.

And silver can fully meet various requirements.

If rare earth elements are added to silver, the performance will be even better.The lifespan of the contact point made of silver added with rare earth elements can be extended several times.

In addition, it is also widely used in photosensitive materials, chemical and chemical materials, and sterilization materials.

For example, photographic film, photographic paper, X-ray film, fluorescent information recording film, electron microscope photographic film and printing film just use a large amount of silver chloride.

This is a very good material.

With the explanation of Won, experts from various countries suddenly understood why silver ions are used for doping in graphene single crystal wafers.

There are two reasons.

The first is that after silver ions are infiltrated into the graphene single crystal wafer by ion implantation, they will be doped in the carbon lattice, thereby improving the conductivity of the doped region.

Just like doping phosphorus and boron ions in silicon-based chips.

The principle is the same, except that the properties of graphene single crystal materials are completely different from those of single crystal silicon wafers.

The second and more important one is that after the elemental silver ions are implanted into the graphene single crystal material through an ion implanter, silver carbide ions will be formed under certain conditions.

Under normal circumstances, silver will not react with carbon, even if it reacts, it will generate silverized carbon, the chemical expression is Ag2C2.

That is to say, carbon atoms and silver atoms are not directly combined, or, at this time, these two elements do not even exist in the standard atomic form, which is closer to an ionic compound.

The ionic compound formed by silver-carbon has no great use except for making an aqueous solution of silver-carbon composite material to prepare electrochemical capacitors.

In addition to Ag2C2 (silver carbide), there is also a carbon nanotube-silver composite nanomaterial, but that is not a hair compound, not even an ionic compound structure, but an artificially processed item. For graphene single crystal wafers Processing doesn't make sense.

This time, South Korean Won used silver ions to ion-dope graphene single crystal wafers, and orbital hybridization technology was used throughout the process.

According to calculations, under the action of certain temperature, pressure and its auxiliary catalytic materials, silver ions will hybridize with some carbon atoms in graphene single crystal.

In this process, the carbon atom can use its s orbital and p orbital to form σ bonds with silver ions through hybridization.

In addition, carbon atoms can also use the remaining p orbitals to superimpose each other and form multiple bonds through Pπ-Pπ interactions.

Under the action of the σ bond and the Pπ-Pπ interaction to form multiple bonds, the carbon-silver hybrid orbital ions will be firmly combined with other carbon atoms that do not participate in the interaction, stabilizing the graphene single crystal wafer and forming a graphene single crystal The circle provides a certain performance of heat resistance and enhances the electrical conductivity of graphene single crystal materials.

This is the basic use after silver ion implantation.

As for the use of silicon ions, it is even simpler.

If the implantation of silver ions can partly be understood as making the expressway more spacious and stable, making it safer for electrons to run on it; then the implantation of silicon ions is to build a toll station for this expressway.

It controls where the electronic car should go and where it should not go.

Don't forget that although the graphene single crystal material is excellent, it has a fatal shortcoming.

That is the bandgap problem of graphene.

This problem is a super-fatal shortcoming for carbon-based chips.

It's as if there are no entrances and exits or toll booths on the highways across the country, all the cars (electronics) will be strung around on them.

High-purity silicon carbide crystal itself is a semiconductor material with excellent performance.

After silicon ions are implanted into the graphene single crystal material, they will form a stable silicon carbide structure with the carbon atoms inside.

Like doping silver ions, through special means, carbon atoms can use its s orbital and p orbital to form σ bonds with silicon ions through hybridization, and can also form multiple bonds in Pπ-Pπ interactions to stabilize graphene. The role of single crystal wafers.

In addition, because of the electronic characteristics of silicon ions, in addition to the s orbital and p orbital possessed by carbon atoms, there is an extra d orbital.

The d orbitals in the silicon ions implanted into the graphene material will participate in the bonding. In addition to forming additional hybrid orbitals such as sp3d and sp3d2, it will also enhance the stability of the Pπ-Pπ interaction to form multiple bonds.

In this way, the graphene single crystal wafer doped twice with silver ions and silicon ions will be stable to a higher level.

The resulting carbon-based chip is not only resistant to high temperatures, but also will not be easily damaged even if it is hit by a strong current.

It avoids accidental or hacker damage, and its performance is more powerful than silicon-based chips.

Won's explanation made the audience in the live broadcast room understand the difference between carbon-based chips and silicon-based chips in the manufacturing process.

It also made experts from various countries focus on the "orbital hybrid theory" again.

This basic and advanced theoretical knowledge of chemistry has attracted the attention of all countries.

From the anchor's explanation, we can know that the "orbital hybridization theory" is far more than it is shown now. Simple.

Even today, orbital hybridization theory has only been used to describe geometries or environments.

But if it develops in the future, in addition to being used to explain the hybridization of atomic orbitals, it can also play a huge role in molecular chemistry, polymer chemistry, and theoretical chemistry through calculations.

This makes all countries pay attention to it.

Although the advanced part of the "Orbital Hybridization Theory" has not yet perfected the closed loop, the degree of emphasis represents the investment in various aspects such as funds, manpower, and material resources.

I believe that in the not-too-distant future, this relatively unpopular major will be full of great vitality.

And that's what the South Korean Won is for.

Whether a civilization can go far depends on the joint efforts of countless people, not the strength of a single person.

Even if he is such an open existence, it is impossible to run with every branch of science and technology in all aspects.

That's obviously unrealistic.

So the 'orbital hybridization theory' used by carbon-based chips is just an introduction.

It leads to orbital hybridization technology and related orbital knowledge, but when countries start to research and develop such theories and technologies, they can naturally extend it to other applications.

It's not that there aren't other fabrication methods for carbon-based chips that won't be in hand.

There are more than a dozen different carbon-based chip manufacturing methods in the "Carbon-based integrated circuit board preparation information".

Not to mention the preparation of graphene, a theoretical basic material.

That is, powder-level carbon nanomaterials such as carbon nanotubes and carbon nanospheres can be used to manufacture carbon-based chips.

Some of them are even better than carbon-based chips made of graphene single-crystal wafers in terms of performance, but South Korea still chose this.

The main reason is that the graphene single crystal wafer leads to the 'orbital hybrid theory'.

And the derived "orbital hybrid theory" can strengthen the chemical knowledge of various countries to a certain extent.

Of course, another reason is that Huaguo has gone the farthest on the road of graphene single crystal wafers, which is the most convenient for Huaguo to receive.

People are selfish, and Korean won is no exception.

Although his goal has changed now, this does not mean that all countries should be treated equally.

Science has no borders, but scientists have borders.

In the simulated space, in the chemical laboratory, Won has completed the processing of graphene single crystal wafers.

The next step is to photoetch it.

That is the so-called photolithography machining.

Ion implantation is not in this step, and ion implantation needs to be processed after the lithography machine is finished.

If a photolithography machine is used to process carbon-based chips, the steps are the same as those for processing silicon-based chips.

The first step is to manufacture wafers. The wafer material for silicon-based chips is single crystal silicon, and for carbon-based chips is graphene single crystal.

Of course, in addition to graphene single crystals, carbon-based chips can also be prepared using carbon nanomaterials such as carbon nanotubes and carbon nanospheres.

This does not conflict.

After the wafer manufacturing is completed and the purity and other conditions meet the requirements, the second step is to coat the wafer.

This step is actually the step of saving the wafer.

After all, whether it is a carbon-based chip or a silicon-based chip, the wafer material will not be used immediately after it is manufactured.

In reality, AMSL is one of the super manufacturers of chips, but its wafer materials are imported.

Its main source is the small island nation.

It takes a long time from production to slicing and transportation of ultra-high-precision monocrystalline silicon wafers imported from small island countries.

Even if the wafers are manufactured and then sliced ​​temporarily during processing, oxidation cannot be avoided.

Therefore, it is necessary to coat the wafer to make it resistant to oxidation and temperature.

As for the material used, it is one of the photoresist materials. When he saved the graphene wafer material before, he used a light-shielding resin.

The third step is photolithography machining.

By coating the wafer with a chemical substance sensitive to ultraviolet light, that is, photoresist, the shape of the chip can be obtained by controlling the position of the light shield.

Then the developing operation is carried out, and the unirradiated or irradiated parts are removed by the solvent, and the chip with the etched circuit diagram can be obtained.

And after this step is over, the fourth step can be carried out: doping with impurities, which is the so-called ion implantation.

Putting the photoetched wafer into a specific chemical ion mixture can change the conduction mode of the doped region.

Some simple chips can use only one layer of wafers, but complex chips, such as CPUs used in mobile phones or computers, have many layers.

Therefore, when manufacturing complex chips, it is necessary to repeat this process continuously, and then open one or more windows at different layers to connect them.

After the fourth step is completed, it is declared that a chip is roughly completed.

The next step is to test it, package it, and then package it, test it, and package it.

All that's left is to sell it and turn it into a bright red note.

(End of this chapter)