Before you officially begin, let's take a risk warning:
All content in this article is a case study of industry research and company research, and does not constitute any investment advice, does not constitute any investment recommendation. There are three other points worth noting:
1. Short-term price fluctuations are almost unpredictable. But the market will be full of God's predictions driven by huge profits.
2. No matter how good the business is, there is a risk of failure if the basic conditions change greatly and the survivor bias is widespread.
3. Good companies with overvalued prices, with tighter liquidity, may also have a long-term correction if profit growth does not meet expectations.
Semiconductor refers to a material with electrical conductivity between conductors and insulators at room temperature, and is the core component of many electronic products. The semiconductor industry is a strategic, basic and leading industry that supports economic and social development and ensures national security, and its downstream is mobile communications, computers, automotive electronics, medical electronics, industrial electronics, artificial intelligence, aerospace and other industries.
Semiconductor silicon wafers are the main carriers of semiconductor devices. Silicon wafer is the upstream raw material of the semiconductor industry, the downstream industry through the silicon wafer lithography, etching, ion implantation and other processing, can be made of silicon wafers into various types of semiconductor devices for subsequent processing, such as integrated circuits, diodes, power devices and so on. Silicon wafers have good insulation as semiconductor materials and are made of semiconductor devices with high stability, so they have been widely used in the semiconductor industry. According to SEMI, the global wafer fabrication materials market totaled $34.9 billion in 2020. Among them, the sales of silicon wafers and silicon-based materials accounted for 36.64%, with sales of about 12.8 billion yuan. Semiconductor silicon wafers account for the highest proportion of the wafer manufacturing materials market and are the core materials of semiconductor manufacturing.
1. Classification
The wafers used in the manufacture of integrated circuits are all monocrystalline silicon wafers, which can be divided into three categories: polished wafers, epitaxial wafers, and silicon SOIs on insulators.
Epitaxial wafer is a kind of semiconductor material, which is a silicon wafer with an epitaxial layer on the substrate. Epitaxial growth (also commonly referred to as epitaxy) is one of the important processes in the manufacture of semiconductor materials and devices. Epitaxial wafers determine about 70% of the performance of the device and are important raw materials for semiconductor chips.
Epitaxial growth is under certain conditions, on the carefully prepared single substrate, along the original crystalline direction to grow a layer of conductive type resistivity, thickness and lattice structure, integrity and other requirements of the new single crystal layer process, the growth of the single crystal layer is called epitaxial layer. At present, the largest amount of epitaxial tablets in the market is GaAs, GaN and SiC epitaxial wafers.
Only bulk monocrystalline materials are difficult to meet the needs of the increasingly developed production of various semiconductor devices. Therefore, at the end of 1959, thin-layer single crystal material growth and epitaxial growth were developed. A layer of high resistivity epitaxial layer is grown on the substrate with very low resistance, and the device is made on the epitaxial layer, so that the high resistivity epitaxial layer ensures that the tube has a high breakdown voltage, and the low resistance substrate reduces the resistance of the substrate, thereby reducing the saturation voltage drop, thus solving the contradiction between the two. In addition, GaAs and other III.-V. groups, II.-VI. groups and other molecular compound semiconductor materials such as gas phase epitaxy, liquid phase epitaxy and other epitaxial technologies have also been greatly developed, has become the vast majority of books microwave devices, optoelectronic devices, power devices and other indispensable process technology, especially molecular beams, metal organic gas phase epitaxy technology in thin layer, superlattices, quantum wells, strain superlattices, atomic-level thin layer epitaxy in the successful application of thin layer, superlattice, atomic-level thin layer epitaxy, for the new field of semiconductor research "energy belt engineering" The pioneering has laid a solid foundation.
The epitaxial layer and the substrate may be the same substance or different substances, called homoepitaxy (homoepitaxy) and the latter heteroepitaxy. According to the supply mode of raw materials, there are gas phase epitaxial, liquid phase epitaxy, solid phase epitaxy, and chemical growth method and physical growth method in gas phase epitaxy. The following figure represents the classification of epitaxy technologies.
SOI (Silicon on Insulator): Silicon on insulator, also known as SOI, is a new type of silicon material with a new structure. The SOI has a sandwich structure, with the top layer of silicon at the top, the buried oxide layer (BOX) in the middle, and the silicon substrate below. The main technologies for preparing SOI are oxygen injection isolation (SIMOX), bonding thinning (BESOI) and intelligent peeling (Smart-Cut), etc. The most mainstream technology is intelligent peeling.
There are many advantages of SOI, including high speed, low power consumption, low cost, and good irradiation resistance. Among them, the most important advantage of SOI is that it can achieve high electrical insulation through the oxide layer, which in turn greatly reduces the parasitic capacitance and leakage of silicon wafers. As semiconductor process processes continue to evolve, the advantages of SOI solutions are becoming apparent.
2. Market conditions
Marketsand Markets estimates that the SOI market will grow at an average CAGR of 29.1% between 2017 and 2022, with a market value expected to reach $1.86 billion in 2022.
The world's wafer suppliers are mainly Shin-Etsu and SUMCO in Japan, Global Wafers in Taiwan, Silicon in Germany and LG in South Korea, and the market share of these five suppliers is as high as more than 92%. In recent years, with the production of a number of wafer wafer factories in the mainland, the gap between supply and demand of domestic silicon wafers has been narrowing, which has also promoted the development of the domestic semiconductor industry chain.
#三安光电 sh600703##Leon micro##华灿光电 #