“Suppose that a hundred years or a few hundred years later, looking back on the relationship between major powers from 2018 to 2019, people in the future may invent a new word, which may be called chip war. Although this kind of war has not yet heard the sound of guns and smoke, but the far-reaching impact on the future world pattern may be no less than a sub-level world war. This is because the trading volume around the international commodity such as chips is several times the total global crude oil trading market today. There have been more than one battles over oil, and the fierce battle over chips will also reconstruct the basic world pattern in the first half of the 21st century.So now everyone
“
Suppose that a hundred years or a few hundred years later, looking back on the relationship between major powers from 2018 to 2019, people in the future may invent a new word, which may be called chip war. Although this kind of war has not yet heard the sound of guns and smoke, but the far-reaching impact on the future world pattern may be no less than a sub-level world war. This is because the trading volume around the international commodity such as chips is several times the total global crude oil trading market today. There have been more than one battles over oil, and the fierce battle over chips will also reconstruct the basic world pattern in the first half of the 21st century. So now everyone hears the word chip almost every day. So what exactly is a chip, and why the design and production of chips has become a high-tech, for most people, I am afraid that they are half-understood, or pretend to understand, which is also a basic attitude. After all, a chip is actually a microcircuit. So what is a circuit? Open the computer case, or the inside of any kind of programmed appliance, and you’ll see the circuit board. A chip is an extremely tiny but powerful miniature logic circuit.
The modern integrated circuit was invented by Kilby in 1958. Therefore, he won the Nobel Prize in Physics in 2000. The inventor of the practical integrated circuit was Noyce, who was unable to win the prize at the same time due to his early death. All Nobel prizes are only awarded to living people. Integrated circuits can integrate a large number of microtransistors onto a small sheet of pure silicon, which is a huge advance. Integrated circuits have two main advantages over discrete transistors: cost and performance. The low cost is due to the fact that the chip prints all components through photolithography as a unit, rather than making just one transistor at a time. The high performance is due to the fast switching of the components, which consumes less energy because the components are small and close to each other. Now it has entered the nanoscale. For example, a 7-nanometer chip can integrate 6.4 billion micro-components in one square centimeter, which is close to the limit of the laws of physics. If you get closer, electrons may directly penetrate the circuit. The space between them is naturally isolated, resulting in the natural failure of the chip circuit. This is the role of Moore’s Law in the field of microelectronics.
Advanced integrated circuits are the heart of microprocessors, or multi-core processors, that control everything from computers to cell phones. Although the cost of designing and developing a complex integrated circuit is very high, the cost per integrated circuit is minimized when spread over products, often in the hundreds of millions. In the end, the profit is lucrative enough.
The basic material for making chips is a thin slice of monocrystalline silicon. Monocrystalline silicon is considered to be the most suitable semiconductor material for large-scale production of integrated circuits after many trials in the early years. Become the grassroots of the mainstream of integrated circuits. Silicon has a high content in the earth’s crust. For example, sand cement contains a large amount of silicon, but it can use monocrystalline silicon with extremely high purity, that is, to extract silicon crystals that do not contain 1/100 millionth of impurities. For crystals, the thicker the diameter, the better. The larger the crystal, the thinner the disc with the larger diameter can be, and more small rectangular chips can be printed on this sheet. The production diameter of a single crystal silicon disc is the first technical indicator of a chip processing company. It took decades to develop defect-free pure single-crystal silicon crystals in the past. In addition to using single-crystal silicon as the substrate for making chips, there are also III-V materials, such as gallium arsenide.
The complete process of manufacturing a single-crystal silicon chip in an assembly line now includes several links such as chip design, wafer fabrication, packaging fabrication, and testing, among which the wafer fabrication process is particularly complex. The first is the chip design, the “pattern” generated according to the needs of the design. The raw material for making chips is wafers. The composition of the wafer is pure silicon, the silicon is refined from quartz sand, and the wafer is silicon purified by 99.9999999%, and then these pure silicon are made into silicon crystal rods, which become the quartz semiconductors for the manufacture of integrated circuits. The material, which is sliced, is the wafer that is specifically required for chip fabrication. The thinner the wafer and the larger the diameter, the lower the production cost, but the higher the process requirements.
Then, the wafer is coated with a film, which can resist oxidation and temperature resistance, and its material is a kind of photoresist. Then there is the lithography development and etching of the wafer. The basic flow of photolithography process. The first is to apply a layer of photoresist to the surface of the wafer or substrate and dry it. The dried wafers are transferred to the lithography machine. The light passes through a mask, and the pattern on the mask is projected on the photoresist on the surface of the wafer to achieve exposure and stimulate the photochemical reaction. A second bake is performed on the exposed wafer, the so-called post-exposure bake, which makes the photochemical reaction more sufficient. Finally, the developer is sprayed onto the photoresist on the wafer surface to develop the exposed pattern. After development, the pattern on the mask is left on the photoresist. If you don’t understand this, you can think of the wafer as the development process of an old-fashioned film camera.
Gluing, baking, and developing are all done in a dispenser, and exposure is done in a lithography machine. Dispensing machines and lithography machines are generally operated online, and wafers are transferred between units and machines by robotic arms. The entire exposure and development system is closed, and the wafer is not directly exposed to the surrounding environment to reduce the impact of harmful components in the environment on the photoresist and photochemical reactions.
This complex process uses chemicals that are sensitive to UV light, which softens when exposed to UV light. The shape of the chip can be obtained by controlling the position of the shade. A photoresist is applied to the silicon wafer so that it dissolves when exposed to UV light. At this time, the first part of the shade can be used, so that the part that is directly exposed to the ultraviolet light is dissolved, and the dissolved part can then be washed away with a solvent. This way the rest is the same shape as the shade, and this effect is exactly what is desired.
The next step is to add impurities and implant ions into the wafer to generate corresponding P and N semiconductors. The specific process is to start from the exposed area on the silicon wafer and put it into a chemical ion mixture. After the above several processes, lattice-shaped grains are formed on the wafer. The electrical characteristics of each die are tested by needle testing. Fix the manufactured wafer, bind the pins, and make various packaging forms according to the needs. After the above process flow, the chip production has been completed, and the final step is to test the chip, remove defective products, and finally package and market.
The Links: ESD7181MUT5G 7MBR25SA120
