Which country has the upper hand in the contest between China and the "foreign countries"? It is said that China hangs on foreign countries, and it is said that foreign countries are easily smashing China on the ground. Both sides have cited examples of the total number of forests and forests. Of course, the centrists must say that each country has its own advantages and disadvantages, but this conclusion is correct but not nutritious. If you want to be knowledgeable on the topic of China and foreign countries, you must first understand what technology is?
What is the core technology?
Classify the technology, the first category is called "can be cottage technology", or "pure burning technology", some people like to burn to the left, some people like to burn to the right, so they burned different application techniques. This is essentially the integration of new gadgets with old technology, such as Saturn V on the US emperor, geotechnical cross-sea bridge, moustache-style tank, and even the Great Wall of China and the Egyptian pyramid. For example, this is a bit like the Guinness Book of Records: the longest hair, the longest nails, etc... This kind of thing, as long as the money is in place, it will be burned out, the key is to see if there is demand, so these can also Calling application technology.
For example, this kind of bridge erecting machine can be carried out by several industrial powers, but it can only be used as a toy, and only the geotechnical work can make money.
After the earthwork was launched, it generated a huge demand, promoted the application technology of various burning money, and earned money and could tirelessly improve various details. Therefore, it can be said that China's application technology has been on par with the whole foreign country.
The second type of technology is temporarily called "not a cottage technology", or "burning money to burn time technology", any equipment, you desperately go to the fine demolition, and finally found that all are material technology.
Making materials and cooking is almost the same. The ingredients of tomato scrambled eggs can tell you, but the dishes you make are not made by me. This is the core technology. In addition to biomedicine, core technology is ultimately material technology. Look at a bunch of examples:
The engine, the jewel in the crown of the industry, is the shortcoming of the most criticized geotechnical. The core technology is that the turbine blades are not strong enough, and the throttle pedals have to be scattered. Whether it is an aerospace engine, an aero-engine, or a gas turbine, as long as the word "machine" is used, the geotechnical waist rod is soft. After: dystocia Chinese heart").
In addition to burning money and burning time, material technology sometimes requires luck. Or take the engine as an example: metal enamel, this thing mixed with nickel, made the turbine blade hoisting days, the world's proven reserves of about 2,500 tons, mainly distributed in Europe and America, 70% used for engine turbine blades This kind of strategic material was properly embargoed by the US emperor. In the past few years, a 176-tonne antimony mine was discovered in Shaanxi. It can be used for earthwork, and it immediately burned the old life.
The rare earth permanent magnet is a magnet made of rare earth, which can maintain magnetic properties at all times and is greatly used. Most of the high-grade rare earth mines are distributed in China, so the technology related to "magnetic", geotechnical than the US imperialism, such as nuclear fusion, space dark matter detection. It is said that the geotechnical embargo on the US imperialism in the past few years, forcing the US emperor to exchange it, and the point of the Shaanxi Anhui plane, the J20 engine is a bit of a look.
As a high-end machine tool of "the mother of industry", geotechnical and male countries are at a level that can only look up to Japan, Germany and Switzerland. Material is one of the biggest limitations. For example, in high-speed machining, the spindle and bearing friction cause thermal deformation, resulting in spindle lifting and tilting, as well as dao wear, etc., so the machining accuracy is extremely high, geotechnical still hopes "The ocean" is sighing.
Optical crystals, some products of geotechnical engineering can also impose embargo on the US imperialism, so the technology related to light is not weak, such as laser weapons and quantum communication. The aerodynamic shape, thanks to the accumulation of Qian Xuesen's generation, the technology associated with it is also a lever.
If we continue to list, we will find that with the application of broad basic materials, China is still lagging behind in foreign countries and applying relatively narrow segments, and China is gradually leading.
Xiaopen friends are sitting right, the focus is coming! This key core material has a total of about 130 species worldwide, which means that as long as you have these 130 materials, you can assemble any equipment already in the world and produce anything you already have.
Human core technology, to a certain extent, refers to these 130 kinds of materials, of which 32% are completely blank in China, 52% are dependent on imports, and the proportions in cutting-edge fields such as high-end machine tools, rockets, large aircrafts, and engines are even more disparate. Domestically produced, but 95% of equipment that produces parts is imported. These are not the things that Chen Sesame is ruining, but the data released by the Ministry of Industry and Information Technology in July 2018. It is still fresh.
The core material technology, saying "foreign countries still put China on the ground", is not excessive. This is actually very easy to understand. After all, it takes a long time to make a home, and material technology not only burns money, but also burns time.
It should be emphasized here that application technology is not more important than core technology. It requires a combination of capital, demand and social reality. Although foreign countries have the ability to burn, they may not have a chance to burn for the rest of their lives. There must be someone here to lift the bar: people just don't want to burn, or kill you in minutes! Oh, if you forcibly burn money, the consequences refer to the old Maozi.
After a long time of tempering, the problem is that the semiconductor chip is difficult because it involves not only the application technology of mass burning, but also the material technology that burns time. In order to facilitate the understanding of the small basin friends, this must be said from the principle.
Chip principle and quantum mechanics
Many illiterate people think that quantum mechanics is just a math game, and there is no application value. Oh, let's find an ancestor for the computer chip. Please see the demonstration:
Conductors, å’± can understand, insulators, å’± can also understand, the small basin friends are physically tidy for the first time, afraid of semiconductors, so first for the physics teacher to put this debt back.
When atoms form a solid, many of the same electrons are mixed together, but quantum mechanics believes that two identical electrons can't stay in one orbit. So, in order for these electrons not to fight in one orbit, many orbits are split. Several tracks, so many tracks crowded together, accidentally close, turned into a wide orbit. This wide track, which is squeezed together by a lot of fine tracks, is called a belt.
Some wide orbits are packed with electrons, and electrons cannot move. Some wide orbits are empty and the electrons can move freely. The electrons can move, and the macroscopic representation is conductive. In turn, the electrons cannot move without being able to conduct electricity.
Ok, let's put things a bit simple, don't mention the concept of "price belt, full belt, forbidden belt, guide belt", and prepare for the focus!
Some full orbits and empty tracks are too close, and electrons can run from full track to empty track without any effort, so they can move freely. This is the conductor. The principle of conduction of monovalent metals is slightly different.
But in many cases there is a gap between the two wide tracks. The electrons alone cannot cross over, and they are not conductive. But if the width of the gap is within 5 ev, adding extra energy to the electron can also cross the empty orbit and move freely across the past, that is, conductive. Such a solid having a void width of not more than 5 ev, sometimes capable of conducting electricity and sometimes not conducting electricity, is called a semiconductor.
If the gap exceeds 5 ev, then it is basically necessary to stop the food. Under normal circumstances, the electrons cannot cross over. This is the insulator. Of course, if the energy is large enough, let alone the 5ev gap, 50ev will still run, such as high-voltage electricity to penetrate the air.
At this point, the energy band theory developed by quantum mechanics is almost shaped. The theory can systematically explain the essential difference between conductors, insulators and semiconductors, that is, depending on the gap between the full orbit and the empty orbit. , depending on the forbidden band width between the valence band and the conduction band.
The principle of semiconductors from the chip is still far away, don't worry.
Obviously, a straight man like a conductor can't be tossed, so the wire is still copper wire today, there is no technical advancement, and the fate of the insulator is similar.
The embarrassing character of semiconductors is the easiest thing to do, so the industries related to electronic devices are basically in the semiconductor industry, such as chips and radar.
Below is a little burning brain cells.
For some simple reasons, scientists use silicon as the base material for semiconductors. The outer layer of silicon has four electrons. Assuming that a solid consists of 100 silicon atoms, its full orbit is filled with 400 electrons. At this time, 10 of the silicon atoms are replaced by 10 boron atoms, and the outer layer of the trivalent element such as boron has only 3 electrons, so the solid orbit has 10 vacancies. This is equivalent to vacating a few empty seats on a crowded bus, providing conditions for the movement of electrons. This is called a P-type semiconductor.
Similarly, if 10 silicon atoms are replaced by 10 phosphorus atoms, there are 5 electrons in the outer layer of the pentavalent element such as phosphorus, so there are 10 more electrons in the full orbit. The equivalent of a crowded bus is hung up by 10 people. These people are very easy to get out of the bus. This is called N-type semiconductor.
Now put PN two semiconductors face to face together will be like? Needless to know, the extra electrons of the N-type must go to the P-type vacancies until the electric field is balanced. This is the famous "PN knot". (The picture is from the blog of Zhang Yun from Science Network)
At this time, a positive voltage is added. The extra electrons of the N-type semiconductor will continuously flow to the vacancy of the P-type semiconductor. The movement of the electron is the current, and the PN junction is electrically conductive.
What if you add a reverse voltage? From the P-type semiconductor, electrons are pumped to the N-type semiconductor, and the N-type is already full of additional electrons. The extra electrons continuously increase the electric field until the applied voltage is cancelled, and the electrons no longer move. The PN junction is Not electrically conductive.
Of course, there will still be weak electronic movements, but they are negligible compared to the forward current.
If you have been stunned, it doesn't matter, sum up in the vernacular: the PN junction has unidirectional conductivity.
Ok, now we have a unidirectional conductive PN junction, then? Connect the PN junction to the wire at both ends, which is the diode. With a diode, set up a circuit:
The triangle represents the diode, the direction of the arrow indicates the direction in which the current can pass, AB is the input, and F is the output. If A does not apply voltage, the current will flow along the line A, and there will be no voltage at the F terminal; if AB is applied with voltage at the same time, the current will be blocked at the other end of the diode, and the voltage at the F terminal will be there. Suppose that there is a voltage as 1 and no voltage as 0. Then only input 1 from the AB terminal, and the F terminal will output 1, which is the "AND gate".
Similarly, to change the circuit to this, then as long as AB has an input 1, the F terminal will output 1, which is called "or gate":
Now with these basic logic gates, it's not far from the chip. You can design a circuit whose function is to change a string of 1s and 0s into another string of 1s and 0s.
For a simple example, applying voltage to the second and fourth inputs is equivalent to outputting 0101. After a particular circuit, the output can be turned into 1010, ie the first and third outputs have voltage.
Let's look at a slightly more complicated bureau:
There are 8 inputs on the left and 7 outputs on the right. Each output corresponds to an LED. Input a string of signals from the left, through the middle of a pile of circuits, so that the other side of the signal is output: 1011011. 1 represents a voltage, 0 represents no voltage, there is a voltage to light the corresponding light tube, that is, 7 light tubes Five lights were lit, so a number "5" was obtained, as shown in the figure above.
Finally, we have figured out how the numbers are displayed! If you want to add 1+1, the complexity of the circuit has exceeded 99% of the IQ, even if Benedict himself, the computing power of the design circuit can not match an abacus.
Until one day, some people used 18,000 tubes, 6,000 switches, 7000 resistors, 10,000 capacitors, and 500,000 wires to form a super-complex circuit. The first human computer was born, weighing 30 tons, and computing power 5000. Times/second, not as much as one tenth of the current handheld calculator. I don't know how many times the engineers at that time had cramped their brains in order to install the pile of circuits.
The next line of thought is simple. How do you integrate these 30 tons of things into the size of your nails? This is the chip.
Chip Manufacturing and Chinese Technology
In order to shrink the 30-ton computing circuit, the engineers threw away all the extra things and made PN junctions and circuits directly on the silicon. Let's start with the silicon wafer and talk about the production process of the chip and the level of China.
First: silicon
By chlorinating this stuff and distilling it, you can get silicon of high purity, and cutting into pieces is the silicon we want. The evaluation index of silicon is purity. If you think about it, if there is a pile of impurities in the silicon, then the electrons don't want to run smoothly between the full orbit and the empty track.
Solar grade high-purity silicon requires 99.9999%, which is more than half of the world's production in China. It has long been played as a cabbage price. The electronic grade high-purity silicon used in the chip requires 99.999999999% (no more, 11 9), almost all depends on imports. Until 2018, Jiangsu Xinhua Company achieved mass production. The current annual output is 0.5 million tons, and China is one year. Imported 150,000 tons.
What is rare is that Xinhua's high-purity silicon is exported to the semiconductor powerhouse Korea, and the quality should be good. However, 30% of manufacturing equipment has to be imported. The traditional hegemony of high-purity silicon is still Wacker of Germany and Hemlock of the United States (US-Japan joint venture), and China has a long way to go.
Second: wafer
When silicon is purified, it needs to be rotated, and the finished product is as long as this:
Therefore, the sliced ​​silicon wafer is also round, so it is called "wafer." Is this word already familiar?
After cutting it, it is necessary to put thousands of circuits on the wafer, and the job is called "fab factory." Think about your brain, how can you complete this operation with current human technology?
Using atomic manipulation? Think more, friend! When you practice the sword flying, humans are not necessarily able to manipulate one atom to form various devices. The process of wafer processing is a bit cumbersome.
First, apply a layer of photographic material on the wafer. This material melts when it sees the light. Where does the light come from? The lithography machine can use a very precise light to pattern the photosensitive material to expose the underlying wafer. Then, with a plasma like this, the exposed wafer will be engraved with a lot of grooves. This device is called an etching machine. By incorporating phosphorus into the trench, a stack of N-type semiconductors is obtained.
After completion, it is cleaned, recoated with photosensitive material, patterned with a lithography machine, engraved with an etching machine, and sprinkled with boron to have a P-type semiconductor.
The actual process is more cumbersome, and the general principle is like this. It's a bit like 3D printing, putting wires and other devices in layers.
The small square on this wafer is the chip. The chip is enlarged and looks like a pile of circuits. These circuits are no better than the circuit of the 30-ton computer. The bottom layer of Zui is a simple gate. It only uses more devices to form a larger circuit, and the performance is naturally improved.
It is said that this is a NAND circuit:
Ask a question: Why don't you make the chip bigger? Can you install more circuits without this? Doesn't performance catch up with foreign countries?
This question is very interesting, the answer is surprisingly simple: money! A 300mm diameter wafer, 100 chips can be made in 16nm process, 210 chips can be made in 10nm process, so the price is half cheaper. In the market, you can kill your competitors, make money and do it. With more research and development, the gap has been widened.
To tell a question, China Jun has basically achieved self-sufficiency with chips, because it doesn't care about money! You can make the chip big. In addition, the larger the silicon wafer, the greater the probability of encountering impurities, so the larger the chip, the lower the yield. In general, the cost of a large chip is much higher than that of a small chip, but for the jun side, this is not a problem.
Don't confuse "Godson" with "Hanxin"
Third: design and manufacturing
With hundreds of millions of devices composing such a huge circuit, think about the scalp numb, so the design of the chip is extremely important, and it is important to compare with the material technology.
An unreasonable setting of traffic lights at an intersection may result in a large traffic jam. The electronics ran around on the chip, and there was a problem with a PN, and the electronics would also be stuck. This kind of intricate circuit design, there is only one way to check, that is: use! A lot of use! Now that you know the importance of chip cost, because you won't spend more money on a computer with the same performance, and chip companies have no market share, it is easy to fall into a vicious circle.
Because of this, the chip design not only needs to burn money, but also needs time to precipitate, which belongs to the core technology of “burning money and burning timeâ€. Since it is a core technology, it will naturally develop an independent company, so there are three types of chip companies: design and manufacturing, design, and manufacturing.
Semiconductors are rare technologies in Taiwan that still lead the mainland. Based on the substantive division of the two sides, China and Taiwan are temporarily separated.
The early design and manufacture are all done together, the most famous: Intel, South Korea, Samsung, Toshiba, Italy, France, STMicroelectronics; China: China Resources Microelectronics, Silan Micro; Taiwan, China: Wang Hong Electronics Wait.
Foreign countries, Taiwan, and the mainland are the most backwards in the mainland. The products are concentrated in the low-end fields such as home appliances remote control. The high-end chips such as shou machines and computers are almost blank!
Later, as the chips became more complex, design and manufacturing were separated, and some companies only designed them into pure chip design companies. For example, Qualcomm, Broadcom, AMD in the United States, MediaTek in Taiwan, Huawei Haisi and Spreadtrum in the mainland.
A few comments.
The famous Qualcomm will not say much, half of the world's shou machine is equipped with Qualcomm chips; Broadcom is the chip supplier of Apple shou machine, shou machine chip ranked second no suspense; AMD and Intel basically put the computer chip. These are all American companies, and the world hegemon is really not blowing.
Taiwan's MediaTek's low-end route, the market share of shou machine chips ranked third, many domestic shou machines are used, such as Xiaomi, OPPO, Meizu. However, it has been a bit miserable by Qualcomm recently, and sales have fallen.
Huawei HiSilicon is the most competitive. Everyone must have seen a lot of stories and they are not expanding. In addition to the communication chip, HiSilicon also used the Kirin chip for the shou machine, and the market share ranked the top five with the growth of Huawei's shou machine. Personal experience, the progress of the Haisi chip is really quite good (this wave of advertising, not a penny of Huawei).
Spreadtrum is a school-run enterprise of Tsinghua University. After all, the mainland chip companies in the early days cannot be shaved by the people. They are on the scalp and take the low-end route. A lot of crises came from some time ago, and later it was said that it was the beginning of change. It was not easy to pass, and there were many differences with the world giants.
There are also a number of chip design companies in the mainland. Morningstar Semiconductor, Lianhe Technology, and Ruiqi Semiconductor are all subsidiaries of Taiwan's big brother. The products are used in TV, portable electronic products and other fields, and they are quite moist.
In the mainland's chip design company, Taiwan has withstood most of the sky!
There is also a type of wafer foundry that is only manufactured or not designed. This must first be said to Taiwan's TSMC. It was the appearance of TSMC that separated the design and manufacture of chips. In 2017, TSMC packaged 56% of the world's foundry business, ranking first in the world in terms of scale and technology, and even surpassing Intel in market value to become the world's number one semiconductor company.
The foundry of Taiwan is the world of Taiwan's big brother. In addition to TSMC, Taiwan has Lianhua Electronics, Powerchip Semiconductor, etc., even the United States and South Korea have to stand by.
The largest foundry in the mainland is SMIC, and Shanghai Huali Microelectronics is also good, but the technology and scale are far less than Taiwan. However, subject to the social situation in Taiwan, TSMC began to lay out the mainland and settled in Nanjing. In recent years, Taiwanese and foreign companies have been madly building a foundry in the mainland. This is a fight with the joint venture cars of the year.
The mainland's SMIC has a 28nm process, and the 14nm production line is also on the road, but unfortunately it has not been profitable. Everyone is still willing to hand over this work to TSMC. TSMC has almost won 70% of the world's 28nm OEM business.
The United States, South Korea, and Taiwan have 10nm processing capabilities. In recent months, TSMC has just launched a 7nm process, and has stabilized its voltage over Samsung. The first customers are Huawei's Kirin 980 chips. These two buddies have long been old partners, Huawei designed chips, TSMC processing chips.
To be honest, if the mainland can integrate Taiwan's semiconductor industry and use flexible policies and a huge market to promote its further upgrading, the pace of geotechnical pursuit of the US emperor is at least half easier. Now, the mainland has a long way to go!
Fourth: core equipment
The chip yield depends on the overall level of the fab, but the processing accuracy is completely dependent on the core equipment, which is the aforementioned "lithography machine".
The lithography machine, the Dutch company Asma (ASML) swept the world! Sorry, the output is not high, you are waiting for it! Whether it is TSMC, Samsung, or Intel, whoever buys the lithography machine from Asma, will be able to take the lead in the 7nm process. No way, it is so powerful!
Japan's Nikon and Canon also do lithography machines, but the technology is far less than Asma. In the past few years, Asma has not been able to find the North, and can only grab the share in the low-end market.
Asma is a high-end lithography machine manufacturer of Weiyi, each selling at least 100 million US dollars. In 2017, only 12 units were produced. In 2018, it is expected to produce 24 units. These have been sold by TSMC Samsung Intel, 2019. There are 40 predictions in the year, one of which is for SMIC.
Since it is so important, can you not make more money? First: Intel has 15% of Asma, TSMC has 5%, Samsung has 3%, and sometimes, money is not omnipotent. Second, the US emperor has completed a "Wassenaar Agreement". Sensitive technologies cannot be sold. China, North Korea, Iran, and Libya are all restricted countries.
Interestingly, in 2009, Shanghai Microelectronics' 90-nm lithography machine was successfully developed (imported core components). In 2010, US Emperor allowed more than 90nm equipment to be sold to China. Later, China began to tackle 65nm lithography machine. In 2015, US Emperor allowed 65nm. The above equipment was sold to China, and then the US Emperor began to be unable to control it. SMIC had the opportunity to leak a high-end machine.
But I don't have to be discouraged. I just want a real estate company, sales are easy to kill Asma, oh yeah!
The importance is second only to the etching machine of the lithography machine. The situation in China is much better. The 16nm etching machine has been mass-produced, and the 7-10nm etching machine is also on the road. Therefore, the US imperially removed the engraving of China. The feng lock of the erosion machine.
Injecting borophosphorus and other elements into the wafer requires the use of an "ion implanter". In August 2017, the first domestic commercial machine was finally available, and the level was not mentioned first. The 70% market share of ion implanters is from Applied Materials. The photographic material was coated with a “gluing machineâ€, and Tokyo Electronics Japan took 90% of the market. Even the auxiliary materials such as photoresist are almost monopolized by Shin-Etsu of Japan and Dow of the United States.
From 2015 to 2020, the domestic semiconductor industry plans to invest 65 billion US dollars, of which equipment investment is 50 billion US dollars, and then 48 billion US dollars for the purchase of imported equipment.
In the past few years, China has invested 13 billion yuan annually, and Intel’s R&D investment has exceeded $13 billion.
On semiconductor equipment, China, no proportion, no way far!
Fifth: sealing and testing
After the chip is completed, it must be cut off from the wafer, connected to the wire, mounted on the outer casing, and by the way, it must be tested. This is called sealing and testing.
Fengfeng is also the world's number one Taiwanese glory, followed by a bunch of powerful companies: Yanpin, Licheng, Nanmao, Xinbang, and Jingyuan Electronics.
The mainland's three major test giants, Changjiang Electronics Technology, Huatian Technology, Tongfu Microelectronics, mixed are not bad, after all, only the end of the chip industry, the technical content is not high.
Chinese core
Speaking of Chinese chips, I have to mention the "Hanxin incident." In 2003, Professor Chen Jin, Dean of the School of Microelectronics of Shanghai Jiaotong University, bought chips from the United States and erased the original marks. As a result of independent research and development, he defrauded countless funds and honors and consumed a lot of social resources. The impact was unprecedented! As a result, for a long time, the scientific research circle talked about the color change, which seriously interfered with the normal development of the chip industry.
Silicon raw materials, chip design, wafer processing, packaging and testing, and related semiconductor equipment, in most areas, China is still in a state of "a long way to go", how long will this kind of aggressive state last? According to the "burning money burning time" theory, the calculation refers to the calculation, about 2030! The Outline of the Development of Integrated Circuit Industry issued by the State wuyuan clearly stated that the main links of the integrated circuit industry chain reached the international advanced level in 2030, and a number of enterprises entered the international first echelon, and the industry achieved leap-forward development.
At present, the overall level of China's chips is almost at the stage of achieving zero breakthrough. Although the market share is minimal, each field has participated in the field and the prospects are still expected.
limit
At the end of the article, habitually complain about the childishness of human science and technology. The chip, as the high-tech level that can be achieved by the sharpening of the head, can only be based on the theory of energy band, and the behavior of electronic still cannot be accurately calculated. Going bigger, don't look at the current complicated technology, it is actually playing with electronics. As for hundreds of other particles, I still don't know how to play!
Chip processing accuracy has reached 7nm, although Samsung brags that it wants to burn to 3nm, but what about? Can you continue to burn? 1nm is almost a few atoms, the quantum effect is very significant, the approximation theory is not good, the behavior of electrons is more difficult to predict, and the semiconductor industry has to stop here.
Burning money, burning time or not, burning to the end is theoretical physics. In addition to burning money, the basic science has to burn people, the burning is extremely fierce, 100 high IQ, 99 are stepping stones! Engineers can be half-way out of the house, but physicists must be born in science, basic science has been neglected in China for more than 5,000 years, and now it is not as good as teasing each year.
I can't just toss the electrons. In order to use the neutrinos too, I am rushing to sneak, oh, no, it is to call for more children to learn basic science!
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