Technology stocks are constantly being speculated in the capital market. How many retail investors understand the basic concepts and classifications of chips semiconductors ? After reading this article, I believe everyone will have a clear understanding of these familiar names.
Let’s start with semiconductors. Semiconductors are substances whose conductivity is between conductors (metals) and insulators (stones), including silicon and germanium. Since silicon has large gaps that can be doped with impurities, it can be used to manufacture important semiconductor electronic components - transistors . The main functions of the transistor are to amplify signals and switch. The transistor is like a radio for data signals. The principle of the radio is to convert weak The signal is amplified and played out using a speaker, and the transistor can amplify the current of the signal and allow the current to pass in a specific way.
Hundreds of millions of transistors are installed on a chip about half a centimeter long and wide. This chip is the well-known " integrated circuit ", commonly known as IC (Integrated Circuit). Therefore, the chip is the abbreviation of integrated circuit, which can also be said is the carrier.
In response to the advent of the intelligent era, technology will change human life patterns. The above article first briefly introduces what semiconductors are, and then details the overall industry overview and future applications.
The following article will be divided into four parts:
- Semiconductor manufacturing process: 4 major steps at a glance
- Integrated circuit classification: 4 major categories according to function
- Semiconductor industry chain operation model: The pros and cons of various models
- Semiconductor application fields: Will be used in the future In these 6 major fields
semiconductor process: 4 The big steps are clear at a glance
1. IC design:
pre-plans the functions of the chip. The functions include arithmetic logic, memory functions, floating point operations, and data transmission. Each function is distributed in various areas on the chip, and the required electronic components are produced. Engineers use the hardware Description language (HDL) is used to design a circuit diagram. After putting the HDL program code into an automated electronic design tool (EDA Tool), the computer converts the program code into a circuit diagram.
2. wafer manufacturing:
purifies and dissolves silicon into a liquid state, and pulls it into a columnar silicon crystal column with a silicon lattice on it. The transistor is placed on the silicon lattice, and the silicon lattice is arranged. It is an important key to installing electronic components. The speed and temperature at which the silicon crystal pillar is pulled up affect the quality of the silicon crystal pillar. The larger the size, the higher the technical difficulty. The 12-inch wafer fab is also relatively 8 The process of the wafer fab is more advanced. The process is technology, but the yield is the most critical. Know-how, the wafer fab uses a diamond knife to cut the entire silicon crystal column into thin slices, and after polishing, it becomes a "wafer". That is the motherboard of the chip. Dust poses a serious threat to these wafers. Therefore, before entering the clean room, manufacturing personnel must wear dustproof clothing, clean themselves and take preventive measures. Wafer manufacturing is 100,000 times cleaner than the operating room. .
3. Photolithography production:
A large circuit design diagram is reduced and imprinted on a silicon wafer, relying on optical principles.
IC The design drawing is engraved on the quartz plate using an electron beam to become a photomask. The design drawing on the photomask is reduced to the wafer. The principle is the same as developing a photo. The "mask" is like a photographic film, and the "wafer" is like photo paper. , the wafer is coated with a layer of photoresist (photosensitive material) in advance, and through ultraviolet light irradiation and the condensing effect of the convex lens, the circuit structure on the mask is reduced and imprinted on the wafer, and the details of the graphics on the mask are It is the key to affecting chip quality.
After the photolithography process is completed, engineers add ions to the wafer and inject impurities into the silicon structure to control conductivity and a series of physical processes to create transistors. After the electronic components such as transistors and diodes on the wafer are produced, copper is poured into the grooves to form precise wiring to connect many transistors.
4. Packaging and testing: After the
wafer is completed, it is sent to the packaging factory. It will be cut into pieces of bare wafers. Since the bare wafers are small and thin, they are very easy to scratch. Therefore, the bare wafers are installed on the lead frame and mounted on the outside. The insulating plastic or ceramic shell is printed with the logo of the entrusted manufacturing company. Finally, the chip is tested to pick out the defective products and the chip is completed.
Integrated circuit (IC) classification: divided into 4 categories according to function.
1. Memory IC:
is mainly used to store original data.
is usually used in computers, TV game consoles, electronic dictionaries, etc. DRAM, SRAM, and NAND Flash are all memory ICs.
2. Logic IC:
mainly processes digital signals (0 and 1). Its products include central processing unit (CPU), microprocessor (MPU), and graphics processing unit (GPU).
3. The main function of micro component IC:
is to be responsible for the communication tasks of CPU peripherals and other components. It is good at processing complex logical operations, mainly digital or text data.
4. Analog IC:
mainly processes related analog signals. ICs are mainly used in power supplies, digital-to-analog converters, etc. due to their ability to withstand high voltage and high current. Semiconductor industry chain operating model: pros and cons of various models. Early semiconductor companies mostly started from IC design, manufacturing, packaging, and testing are all handled by one person. Due to Moore's Law, chip design is becoming increasingly complex and expensive. A single semiconductor company cannot bear the high R&D and production costs from upstream to downstream. By 1980 At the end of the period, the semiconductor industry gradually moved towards a professional division of labor model to create greater profits and improve product stability.
Moore's Law:
Proposed by Gordon Earle Moore, one of the founders of Intel, the number of transistors that can be accommodated on an integrated circuit will double approximately every 18 months, and the performance will also double.
According to the nature of the business, the semiconductor industry is mainly divided into the following four business models:
1. Integrated manufacturer (IDM) model:
integrates multiple industry chain links such as chip design, manufacturing, packaging, testing, and sales, and requires strong working capital capabilities. To support this operating model, only a few large manufacturers can maintain it at present.
2. Foundry mode:
only needs to be responsible for manufacturing, packaging, and testing. It can serve multiple design manufacturers at the same time. However, due to competition among suppliers, special attention must be paid to the leakage of customer confidential technologies. The factory's main competitiveness comes from large-scale production and production control.
3. Fabless IC designer (Fabless) model:
is only responsible for chip circuit design and sales, and outsources production, packaging, and testing. At first, the capital scale was small, and the entry threshold was relatively low.
4. Chip design service provider (Design Service) model:
provides chip design companies with corresponding tools, circuit design architecture, consulting services, etc. It does not design and sell chips, but sells intellectual property rights - design drawings, also known as silicon Intellectual Property (SIP).
Semiconductor application areas: These 6 major areas will be used in the future
According to the International Semiconductor Industry Association, semiconductors will be mainly used in smart transportation, smart medical care, smart data, smart manufacturing , green manufacturing and advanced manufacturing in the future. Transportation and industrial manufacturing are the two main driving forces. The level of smart vehicle driving assistance safety systems is getting higher and higher. Through back-end AI chip calculations, it receives sensing signals, analyzes them through calculations, and then transmits them to the vehicle power system. It can complete the needs of safe avoidance and arrival at the destination, and realize all-round The vision of autonomous driving. Industrial manufacturing has evolved from digitalization to fully automated production, and the Internet of Things system has been introduced into the production management system, promoting a new era of industrial smart manufacturing and driving overall semiconductor market demand.
In the future 5G, AI is closely related to the semiconductor industry. The advent of the 5G era will drive the entire semiconductor peripheral products. For example, the market demand for 5G smartphones is nearly 200 million units, which will bring about another wave of replacement. AI intelligence requires a large amount of computing Performance requires continuous innovation of wafer technology to adapt to rapid technological changes. The semiconductor industry is expected to reach new heights in the future.
