In our daily work and life, we often use a variety of electronic or electrical products, such as computers, mobile phones, TVs, refrigerators, washing machines, etc.
These products, if we take it apart, we all see a green board like this.
Sometimes it's blue or black.
As we all know, this green board is called a circuit board. The more official name is printed circuit board, that is, PCB (printed circuit board, sometimes called PWB, printed wire board abroad).
On the PCB, a lot of electronic components are soldered, such as capacitors, resistors, inductors, etc.
We can also see that there are some black square elements.
That's right, this component is likely to be a chip (English name is chip).
Definition of a chip.
Chip, in fact, is a more general name.
For electronic devices, it is hidden inside, and it is very important, equivalent to the engine of a car and the heart of a person, so it is called "core". From the point of view of form, it is one by one, so it is called "piece". Taken together, it is a "chip".
Generally speaking, a chip is an integrated circuit. The two can be equated and used interchangeably. Integrated circuits are relatively easy to define. Through specific technology, electronic components such as transistors, resistors, capacitors, and diodes are integrated on a single substrate to form a miniature circuit, which is called an integrated circuit.
If the substrate is made of semiconductor materials (such as silicon), or if the integrated circuit is made of semiconductor material wafers, it belongs to semiconductor integrated circuits. The integrated circuits we talk about in the traditional sense basically refer to semiconductor integrated circuits. Therefore, sometimes the words semiconductor, chip, and integrated circuit are often mixed.
If you pick carefully, there are still some differences between chips and integrated circuits.
Some industry views believe that integrated circuits are circuits and basic units, mainly emphasizing the realization of a certain function, such as a certain logical operation. In scenarios such as circuit design, this term will be used more often.
Chips, on the other hand, are a more macroscopic and product-oriented concept. After design, manufacturing, packaging, and testing, a ready-to-use product form is considered to be a chip. When emphasizing the use, people will use the name "chip" more, such as CPU chips, AI chips, baseband chips, etc.
Some people also define a chip as "a general-purpose semiconductor component product that contains one or more integrated circuits and can achieve a specific function". In other words, chips are a general term for semiconductor component products.
Classification of chips.
A chip is a set of circuits that implement a specific function. It has the characteristics of modularity, which can facilitate manufacturers to quickly carry out product design and development, reduce the difficulty of development, and shorten the development cycle.
Over the past few decades, semiconductor processes have developed rapidly under the guidance of Moore's Law, and the size of chips has become smaller and smaller, and more and more circuits have been housed inside, which has greatly reduced the size, cost and power consumption of electronic products.
It not only improves our quality of life, but also leads the information technology revolution and promotes the progress of the entire human civilization.
With the chip, there is the mobile phone.
Nowadays, chips have formed a very wide range of applications, and many categories have been derived.
The classification method of the World Semiconductor Trade Statistics (WSTS) is more authoritative and official. They divided all IC categories into analog, micro, logic, and memory.
At the unofficial level, the classification is more arbitrary.
According to the function, we often divide the chip into: computing chip, memory chip, communication chip, perception chip, energy chip, interface chip.
The types of chips that we are more familiar with are as follows:
We can also divide it according to the process, such as 28nm, 14nm, 7nm, and 5nm, which we often hear about. Alternatively, it can be divided according to semiconductor materials, such as silicon (Si), germanium (Ge), gallium arsenide (Gaas), gallium nitride (GaN), etc.
In fact, in addition to electrical chips, we have also developed optical chips (such as silicon photonics) that use light instead of electricity to transmit signals.
From the perspective of integrated circuits, there are many classifications. According to the manufacturing process, integrated circuits can be divided into semiconductor integrated circuits and film integrated circuits (film integrated circuits use metals and ceramics, etc.). Thin film integrated circuits are further divided into thick-film integrated circuits and thin-film integrated circuits.
According to the circuit attributes, we can also be divided into digital integrated circuits, analog integrated circuits and mixed-signal integrated circuits.
Digital integrated circuits, as the name suggests, deal with digital signals. It appears most around us, such as microprocessors (CPUs, GPUs, etc.), digital signal processors (DSPs) and microcontrollers (MCUs), etc., which are all digital integrated circuits.
Analog integrated circuits are mostly used in sensors, power chips, op amps, etc., and are mainly used for amplification, filtering, demodulation, mixing and other functions of analog signals.
Mixed-signal integrated circuits are analog and digital circuits integrated on a single chip. As you can guess, analog-to-digital (ADC) and digital-to-analog (DAC) conversion chips belong to this category.
According to the number (scale) of microelectronic devices integrated on the chip, integrated circuits can be divided into the following categories:
To be more professional, according to the type of conduction, integrated circuits can also be divided into bipolar integrated circuits and unipolar integrated circuits.
The manufacturing process of bipolar integrated circuits is complex and the power consumption is large, which means that there are types of integrated circuits, such as TTL, ECL, HTL, LST-TL, and STTL.
The manufacturing process of unipolar integrated circuits is simple, the power consumption is also low, and it is easy to make large-scale integrated circuits, which represent integrated circuits such as CMOS, NMOS, PMOS, etc.
The internal structure of the chip.
As we mentioned earlier, the chips look like black square flakes.
Sometimes, it also has a silver metal cover (for added protection and heat dissipation). For example, our CPU:
CPU cover.
CPU appearance.
The chip becomes like this after it has been encapsulated, a process in the chip manufacturing process.
We take the "shell" out to really see the inner core of the chip. Looking at it with a microscope, it looks like this:
The outer circle is the pin (pin). A thin thread is a lead wire. The square part in the middle is the real circuit of the chip.
If you continue to zoom in, it looks like this:
Swap it out for a 3D effect, and it looks like this:
That's right, it's all three-dimensional, there are many, many layers, densely packed, like a super maze, but also like a futuristic city.
On the diagram, one by one, they are all connected. And the object they are connected to is the transistor.
The number of transistors in a chip usually represents the capability of the chip. The more transistors, the more circuits, the more powerful and powerful the computing power. Nowadays, when many manufacturers release chips, they will always emphasize how many transistors they have in the chip, which is what it means.
Nvidia's H100 GPU, with 80 billion transistors.
Chips come in simple (relatively speaking) and complex ones. Some complex chips will also be divided into different functional modules. Together, these modules form a system that becomes SoC (System on Chip).
Our mobile phone main chips, such as Qualcomm Snapdragon, MediaTek Dimensity, and Huawei Kirin, are all typical SoC chips. The chip includes CPU, GPU, APU, ISP, baseband, radio frequency, and so on.
Author: Xiao Zaojun.
*The content represents the author's views only.
It does not represent the position of the Institute of Physics of the Chinese Academy of Sciences.
If you need it, please contact the original***
*: Fresh jujube class.
Edit: serendipity