Views: 0 Author: 山川 Publish Time: 2024-08-29 Origin: 新型陶瓷
Silicon carbide materials mainly include single crystal and ceramics 2 categories, whether as a single crystal or ceramics, silicon carbide materials have become one of the key materials of semiconductor, new energy vehicles, photovoltaic and other three billion track. For example:
in terms of single crystal, silicon carbide, as the most mature third-generation semiconductor material at present, can be described as the most hot semiconductor material in recent years. Especially in the context of the "dual carbon" strategy, silicon carbide is deeply bound to energy-saving and carbon reduction industries such as new energy vehicles, photovoltaic, energy storage, and so on.
In ceramics, silicon carbide with its excellent high temperature strength, high hardness, high elastic modulus, high wear resistance, high thermal conductivity, corrosion resistance and other properties, in recent years with the new energy vehicles, semiconductors, photovoltaic and other industries to take off and demand erupted, deeply into the key links in the industrial chain of these emerging fields.
Today, we respectively from the direction of single crystals and ceramics, look at how silicon carbide materials in these hot track is a big kill.
Single crystal/semiconductor
Come out of nowhere to solve the performance needs of silicon-based devices that are difficult to meet
Silicon has long been the most commonly used material for manufacturing semiconductor chips, and more than 90% of semiconductor products are currently made of silicon as a substrate. The reason is that the silicon reserve is large, the cost is relatively low, and the preparation is relatively simple. However, the application of silicon in the field of optoelectronics and high-frequency high-power devices has been hindered, and the performance of silicon at high frequencies is poor, and it is not suitable for high-voltage application scenarios. These limitations have made it increasingly difficult for silicon-based power devices to meet the high power and high-frequency performance needs of devices in emerging applications such as new energy vehicles and high-speed rail.
In this context, silicon carbide has come into the spotlight. Compared with the first and second generation semiconductor materials, SiC has a series of excellent physical and chemical properties, in addition to band gap width, but also has a high breakdown electric field, high saturation electron velocity, high thermal conductivity, high electron density and high mobility characteristics. The critical breakdown electric field of SiC is 10 times that of Si and 5 times that of GaAs, which improves the voltage capacity, operating frequency and current density of SiC based devices, and reduces the on-loss of devices. Coupled with higher thermal conductivity than Cu, the device does not need additional heat dissipation device when used, reducing the volume of the whole machine. In addition, SiC devices have extremely low on-off losses and can maintain very good electrical performance at very high frequencies. For example, switching from a three-level scheme based on Si devices to a two-level scheme based on SiC can increase efficiency from 96% to 97.6% and reduce power consumption by up to 40%. Therefore, SiC devices have great advantages in low power consumption, miniaturization and high frequency application scenarios.
Silicon carbide devices have become the "cake" pursued by hot tracks such as new energy vehicles and photovoltaics.
(1) New energy vehicles
Silicon carbide material can make the device volume smaller and smaller, and the performance is getting better and better, so in recent years, electric vehicle manufacturers have favored it. Five years ago, Tesla took the lead in using silicon carbide on the model3 main drive inverter, opening up the first silicon carbide "on the car". After that, BYD, Geely, SAIC Volkswagen, NIO and other car companies accelerated the layout, increased the horsepower in improving the driving range, achieving super fast charging, achieving V2G functions, etc., and the continuous growth of electric vehicle sales also led to the market demand for silicon carbide power devices, setting off a silicon carbide "car heat" that continues to this day.
In addition, in vehicle chargers, the use of silicon carbide can obtain faster switching frequency FSW, higher efficiency, two-way operation, smaller passive components, smaller system size and lower system costs. Therefore, at present, according to the characteristics of silicon carbide devices and the development trend of electric vehicles, silicon carbide devices or future electric vehicles are the inevitable choice.
(2) Rail transit
Compared with traditional silicon-based IGBT, silicon carbide power devices can effectively increase the switching frequency and reduce the switching loss, and its high-frequency can further reduce the noise, temperature, volume and weight of passive devices, improve the mobility and flexibility of device applications, which is the mainstream development direction of a new generation of traction inverter technology. At present, SiC devices have been applied in urban rail transit systems, and train 0312 of Suzhou Railway Line 3 is the first permanent magnet direct drive traction system project based on SiC converter technology in China, achieving the goal of 20% traction energy saving. In 2012, the Tokyo Metro Ginza Line carried out the world's first SiC device loading operation test. Since 2015, Japan has begun to adopt a large number of SiC devices on railway vehicles, and by 2021, it has entered the stage of widespread application.
All silicon carbide permanent magnet direct drive subway train
(3) photovoltaic power generation
In photovoltaic power generation applications, the cost of traditional inverters based on silicon-based devices accounts for about 10% of the system, but it is one of the main sources of system energy loss. After more than 40 years of development, the conversion efficiency and power density of silicon-based devices have approached the theoretical limits. The use of silicon carbide materials can increase the conversion efficiency from 96% to more than 99%, reduce energy consumption by more than 50%, and increase the cycle life of the equipment by 50 times. For example, in string inverters for photovoltaic systems in residential and commercial facilities, silicon carbide devices bring cost and performance benefits at the system level. Leading photovoltaic inverter companies such as solar Power have applied silicon carbide devices to their series inverters.
(4) Smart grid
Silicon carbide power switch because of its extremely low open state resistance, and can be applied to high pressure, high temperature, high frequency occasions, is an ideal replacement for silicon-based devices, if the use of silicon carbide power module, compared with the use of silicon power supply device, the power loss caused by switching loss can be reduced by more than 5 times, the volume and weight reduced by 40%, It will have a significant impact on the future power grid form and energy strategy adjustment.
(5) Wireless communication facilities
The development of 5G has promoted the growth of demand for silicon-based gallium nitride devices, and the market space is broad. In microwave RF devices, power amplifiers directly determine key parameters such as wireless communication distance and signal quality between mobile terminals and base stations, and 5G communication features such as high frequency, high speed and high power have higher requirements for its performance. Gallium nitride RF devices with silicon carbide as substrate have the advantages of high thermal conductivity of silicon carbide and high power RF output of gallium nitride in high frequency band, and their applications in power amplifiers can meet the requirements of 5G communication for high frequency performance and high power processing capacity.
Capital bets, silicon carbide in the semiconductor winter
In the semiconductor industry's down cycle, it is not a gloomy sound, silicon carbide is a counterexample of the malaise. In recent years, the capital market has been strongly concerned about silicon carbide.
In 2021, a number of silicon carbide enterprises have won the favor of investment institutions, and have announced the completion of financing, and the industry has also stirred up a wave of financing.
2022 is also a year of silicon carbide investment and financing. According to incomplete statistics, the annual amount of investment, financing and mergers and acquisitions in 2022 exceeded 3.3 billion yuan, and the number reached more than 30. Just in December 2022, there were seven financing cases, including Zhen Drive Technology, core Poly Energy, Yiwen Technology, Zhanxin Electronics, Nansha Wafer, etc.
Just after the first half of 2023, the amount of financing of silicon carbide enterprises has hit a new high in the last three years. Q1 this year, a total of 21 financing in the silicon carbide field, including epitaxy, substrate, materials, equipment, power devices... Financing covers almost the whole domestic silicon carbide industry chain. Among these 21 enterprises, in addition to some enterprises did not disclose the amount of financing, 10 enterprises received more than 100 million yuan of financing, accounting for about 50% of the total. Among them, the largest financing is Tianyu Semiconductor, which is 1.2 billion. In Q2 this year, there were more than 10 financing, with a total amount of more than 5 billion yuan.
Building factories and expanding production has not stopped
Data show that in the first half of the year, the expansion projects related to silicon carbide and the expected capital expenditure add up to a total amount of more than 100 billion yuan (converted into RMB), the content of the expansion is mainly around the substrate, epitaxy, and devices, and the direction of application is mostly based on electric vehicles.
In January this year, Germany's Bosch Group released a major news in Suzhou: invest another $1 billion to build new energy vehicle core components and autonomous driving R & D and manufacturing base project, the production content includes silicon carbide power modules. Then in April, Bosch decided to buy semiconductor manufacturer TSI Semiconductors and invest another $1.5 billion to expand third-generation semiconductor production to meet the demand of the electric vehicle market.
In February this year, Wolfspeed, an American semiconductor manufacturer, officially announced plans to build the world's largest and most advanced silicon carbide device manufacturing plant in Saarland, Germany. The facility will be the largest eight-inch semiconductor facility in the world, using an innovative manufacturing process to produce next-generation silicon carbide devices.
At the same time, the domestic silicon carbide production expansion action has not stopped.
In June this year, SAN 'an Optoelectronics and stmicroelectronics jointly announced that the two sides intend to invest $3.2 billion (about 22.8 billion yuan) to build an 8-inch silicon carbide epitaxial chip foundry. At the same time, SAN 'an Optoelectronics will establish an 8-inch silicon carbide substrate factory as a supporting facility, with an estimated total investment of 7 billion yuan. In addition, Tianke Heda, Han Tiantian, Tianyue Advanced and other companies have announced their new investment and expansion plans.
Ceramic aspect
Ceramics, the common ceramic materials are silicon carbide, alumina, silicon nitride, etc., which silicon carbide materials because of its very high elastic modulus, thermal conductivity and low thermal expansion coefficient, not easy to produce bending stress deformation and thermal strain and other characteristics, as excellent structural ceramics and high temperature materials, in lithium, semiconductor, photovoltaic and other fields have been more and more applications.
A popular material for precision components of semiconductor equipment such as lithography machines
Ceramic is a key component material in key semiconductor equipment such as etching machine, coating developer, lithography machine, ion implantation machine, and its cost has accounted for more than 10% of the cost of semiconductor equipment. Among them, silicon carbide ceramics are widely used in the process equipment from the front to the back of semiconductor manufacturing, such as in grinding and polishing suckers, lithographic suckers, detection suckers, precision motion platforms, high-purity silicon carbide parts of the etching link, precision motion systems in the packaging and detection link, etc., which are extremely important.
(1) In the lithography machine
In high-end lithography machines, in order to achieve high process accuracy, it is necessary to widely use ceramic parts with good functional compound, structural stability, thermal stability, dimensional accuracy, such as E-chuck, Vacumm-chuck, Block, magnetic steel frame water cooling plate, mirror, guide rail, etc. In this regard, silicon carbide ceramics are adequate.
(2) In etching equipment
In the etching equipment, the plasma through physical action and chemical reaction will cause serious corrosion on the surface of the equipment device, on the one hand to shorten the service life of the parts, reduce the performance of the equipment, on the other hand, the reaction products generated during the corrosion process will volatilize and fall off, and produce impurity particles in the process chamber, affecting the cleanliness of the chamber. Therefore, the plasma etching resistance of the cavity and the cavity component materials becomes very important.
SiC as an etching machine cavity material, compared with quartz, the material itself produces less impurity pollution, due to more excellent mechanical properties, in the plasma bombardment of its atomic surface, the atomic loss rate is relatively small, Mitsui reported a SiC composite material as an air etching machine cavity material, with high corrosion resistance.
In terms of focusing ring components, their role is to provide a balanced plasma, requiring a similar conductivity to that of silicon wafers. The material used in the past was mainly conductive silicon, but the fluorine-containing plasma reacted with silicon to form volatile silicon fluoride, which greatly shortened its service life, resulting in frequent replacement of components and reduced production efficiency. SiC and single crystal Si have similar conductivity, and better resistance to plasma etching, and can be used as a focusing ring material.
As the key consumable of semiconductor material in plasma etching, SiC etching ring has high purity requirement. Generally, only the CVD process can be used to grow SiC thick layer blocks, and then it is prepared by precision machining, mainly for the preparation of semiconductor etching process.
Silicon carbide ceramic kiln - "behind the scenes workers" of lithium electric materials sintering
As a new energy branch, there is no need to describe how much lithium is currently burning. Lithium ion battery anode material, anode material and electrolyte drying, sintering and heat treatment and other processes, roller kiln is a key continuous production equipment, kiln furniture is the key accessories of the kiln, its industrial kiln recycling, used to support or protect the burnt products of refractory products, driven by the positive material expansion, the application of kiln furniture expanded. Silicon carbide ceramic kiln with its excellent high temperature mechanical properties, fire resistance and thermal shock resistance used in ceramic kiln, can improve the production capacity of kiln, greatly reduce energy consumption, become a variety of kiln materials in the ideal choice of kiln materials.
Photovoltaic industry - Key vehicle materials in the cell production process
Among silicon carbide ceramics, silicon carbide boat bracket has become a good choice for key vehicle materials in the production process of photovoltaic cells, and its market demand has been increasingly concerned by the industry.
At present, the commonly used quartz boat brackets, boat boxes, pipe fittings, etc. are limited by domestic and international sources of high-purity quartz sand, with small production capacity, and under the background of the increasing demand for single-crystal furnace crucible in the upper reaches of the photovoltaic industry and silicon battery carrier consumables in the middle reaches, high-purity quartz sand has the characteristics of tight supply and demand and long-term high price operation. As a device that carries silicon in the production process of photovoltaic cells, quartz carrier has stable performance, but it runs counter to the selection standard of consumables with high quality and low price.
Compared with quartz materials, silicon carbide materials made of boat brackets, boat boxes, pipe products and other good thermal stability, high temperature use without deformation, no harmful precipitation of pollutants, as an excellent alternative material for quartz products, the service life can reach more than 1 year, can significantly reduce the use of costs and maintenance and repair line loss caused by production, cost advantages are obvious. As a vehicle, it has a broad application prospect in the photovoltaic field.
At present, the photovoltaic penetration rate of the world's major economies continues to increase, driven by national policy guidance and market demand, with the photovoltaic industry's electricity cost significantly reduced, photovoltaic power generation has become the world's most economic power energy, according to the IEA forecast, 2020-2030 photovoltaic installed capacity will grow at a CAGR of 21% to close to 5TW. Pv's share of global installed power will increase from 9.5% to 33.2%.
Terminal strong installed demand continues to drive the high demand for battery cells, promote the photovoltaic industry silicon carbide boat bracket and boat box replacement demand rise, is expected to 2025 semiconductor and photovoltaic industry with silicon carbide structure ceramics accounted for 62%, of which the photovoltaic industry with silicon carbide structure ceramics will rise from 6% to 26% in 2022, becoming the fastest growing area.
Brief summary
We see that silicon carbide material, whether as a single crystal material or as a ceramic material, has occupied a very important position in the industrial chain of semiconductor, lithium battery, photovoltaic and other most popular industries today, and its three industries are more than 100 billion market scale circuit, and these industries are growing at a high speed, it can be predicted that silicon carbide material tomorrow is a good.
