Industry Analysis of Electromagnetic Shielding and Thermal Conductive Materials and Devices

1.1 Electromagnetic shielding and thermal conductivity products are widely used in consumer electronics and communication equipment

The widespread use of high-performance communication devices, computers, smartphones, automobiles and other terminal products has driven the rapid expansion of electromagnetic shielding and thermal conductivity devices and related industrial applications, and the application of products has also deepened. At the same time, the application of electromagnetic shielding and thermal conductivity devices in electronic products can greatly improve the product quality and performance of electronic products.

The 5G era is gradually approaching, with the introduction of high frequencies, upgrading of hardware components, and exponential growth in the number of networked devices and antennas. Electromagnetic interference between devices and within devices themselves is ubiquitous, and the harm of electromagnetic interference and radiation to electronic devices is becoming increasingly severe. Along with the updates and upgrades of electronic products, the power consumption of devices continues to increase, and the heat generation also rapidly increases. The bottleneck of high-frequency and high-power electronic products in the future is the electromagnetic radiation and heat they generate. To solve this problem, more and more electromagnetic shielding and thermal conductivity devices will be added in the design of electronic products. thereforeElectromagnetic ShieldingThe role of heat dissipation materials and devices will become increasingly important, and demand will continue to grow in the future.

In the 2G era before the popularization of smartphones, mobile phones were less affected by electromagnetic shielding and heat dissipation. With the advent of the 3G smartphone era, the hardware configuration of mobile phones is becoming higher and higher. CPUs are constantly upgrading towards multi-core high performance, and the trend towards large-sized and high-resolution screens is evident. Communication speeds are also constantly improving. Along with the upgrading of mobile phone hardware, the demand for electromagnetic shielding and heat dissipation is constantly increasing, driving the continuous enrichment and innovation of electromagnetic shielding and thermal conductivity device product types.

It can be foreseen that in the 5G era, smartphones will undergo significant improvements in transmission speed, frequency, signal strength, and other aspects. From core chips to RF devices, from body materials to internal structures, 5G smartphone components will usher in new changes. Hardware innovation and upgrading have put forward new requirements for electromagnetic shielding and thermal conductivity of smartphones. In the future, it is expected to further present trends such as diversified types, process upgrades, and increased single machine usage, driving further growth in single machine value. Therefore, electromagnetic shielding and thermal conductivity products have a broader application space in the 5G era.

1.2 The scale of electromagnetic shielding and thermal conductivity industry continues to grow in the 5G era

In recent years, with the continuous upgrading of software and hardware technology, innovation in consumer electronics products, and upgrading of communication equipment, the market for electromagnetic shielding and thermal conductive materials has steadily grown. According to BCC Research's forecast, the global market size of EMI/RFI shielding materials will increase from $6 billion in 2016 to $7.8 billion in 2021, with a compound annual growth rate of nearly 6%Interface thermal conductive materialThe market size will increase from 760 million US dollars in 2015 to 1.1 billion US dollars in 2020, with a compound growth rate of over 7%.

And belong to emerging industriesGraphite heat dissipation materialSince its large-scale application in consumer electronics products in 2011, it has shown a rapid development trend in recent years. Calculated at a unit price of 150-200 yuan/square meter, the current market size of high thermal conductivity graphite materials in the consumer electronics field has reached nearly 10 billion yuan.

Due to the full arrival of the 5G era after 2020, the short-term market size forecast mentioned above is mainly based on the upgrade demand of existing devices, without considering the incremental factors after the large-scale commercialization of 5G. It can be foreseen that with the rapid development of downstream markets in the 5G era, there will be a huge incremental demand for electromagnetic shielding and thermal conductive materials and devices. Therefore, we believe that after 2021, the growth rate of the electromagnetic shielding and thermal conductive materials market is expected to further significantly increase on this basis.

According to Gartner's forecast, as 5G smartphones are expected to be launched in 2019, 9% of smartphones in the market will support 5G networks by 2021. Therefore, annual sales of 5G smartphones will exceed one billion units after 2021. According to the "Three Year Action Plan for Major Information Infrastructure Construction Projects" issued by the National Development and Reform Commission and the Ministry of Industry and Information Technology in early 2017, the total number of 4G base stations in China will increase by 2 million on the basis of 2015 by 2018, totaling about 4 million. Roughly assuming that the number of 5G low-frequency base stations is equivalent to that of 4G base stations, and the number of high-frequency base stations is roughly equivalent to that of low-frequency base stations, the total demand for 5G base stations in the future will reach nearly 8 million, which is expected to double the existing scale.

The mobile terminals and base stations in the 5G era have generated a significant incremental demand for electromagnetic shielding and thermal conductivity products. Coupled with the trend of process upgrades, this can bring about a significant increase in the value of individual machines, thereby promoting the market size of the electromagnetic shielding and thermal conductivity industry to double after the full arrival of the 5G era.

Taking thermal conductive graphite as an example, 5G mobile phones are expected to adopt customized thermal conductive graphite solutions in more key component areas. At the same time, composite and multi-layer high thermal conductive films are expected to be more widely used due to their better heat dissipation effects, which will significantly increase the value of thermal conductive graphite as a standalone device. Assuming that the unit price of thermal graphite in future 5G phones is 2.5 times that of 4G phones, with the increase in penetration rate of 5G phones, the market size of thermal graphite applied to smartphones is expected to double or more.

From this, it can be seen that with the penetration of 5G smartphones and the significant increase in single machine usage and types, electromagnetic shielding and thermal conductivity products are expected to achieve faster growth. Considering the increase in the speed and number of 5G communication base stations, as well as the complexity of processing frequency bands, the electromagnetic signals and heat generated by themselves have significantly increased, driving more demand for electromagnetic shielding and thermal conductivity products; In addition, the maturity of 5G technology is expected to promote smart wearables VR/AR、 The rise of emerging intelligent terminals such as smart driving cars has brought more diverse application areas for electromagnetic shielding and thermal conductivity. Therefore, with the full arrival of the 5G era, the increase in the value of single machines combined with the increase in the number of terminal devices, the market size of electromagnetic shielding and thermal conductivity materials and devices is expected to grow exponentially.

2. The pace of upgrading new processes and materials is not limited

Downstream consumer electronics products have unique requirements for electromagnetic shielding and thermal conductivity due to their personalized design, greatly promoting the application and innovation of various electromagnetic shielding and thermal conductivity devices. With the increasing influence of electromagnetic shielding and thermal conductivity in downstream industries, more and more information electronic equipment manufacturers need to introduce electromagnetic shielding and thermal conductivity functional design at the beginning of design, which has become an important component of electronic product development stage. Enterprises must conduct a comprehensive analysis of the products they apply based on the needs of downstream users, provide fully personalized electromagnetic shielding and thermal conductivity services from a system perspective, and provide customized electromagnetic shielding and thermal conductivity application solutions for customers to meet their all-round needs with optimized design, suitable material selection, and cost-effectiveness.

Smartphones are constantly innovating and developing towards slimness, integration, and miniaturization of devices, while the arrival of the 5G era brings higher requirements for electromagnetic shielding and heat dissipation, promoting future technological upgrades for electromagnetic shielding and thermal conductivity devices; At the same time, the continuous development of emerging materials themselves and the continuous innovation of surrounding technologies will also promote the application of more and more types of materials in electromagnetic shielding and thermal conductivity.

2.1 Thermal Conductive Materials and Devices: Thermal conductive graphite film has a wide range of application prospects

With the gradual increase and complexity of integrated functions on single electronic devices in the 5G era, as well as the shrinking size of the devices themselves, higher requirements have been put forward for the thermal management technology of electronic devices, such as the increasing demand for the thermal conductivity coefficient of thermal conductive materials and the thermal stability of long-term operation. This trend provides an opportunity for the development of thermal conductive materials, which are used at the contact interface between heat sources and heat sinks to improve thermal conductivity efficiency and effectively solve the heat dissipation problem of high-power electronic devices.

In thermodynamics, heat dissipation refers to the transfer of heat through three main methods: conduction, convection, and radiation. According to the heat transfer method, the heat dissipation system of electronic devices can be composed of fans, heat sinks (such as graphite sheets, metal heat sinks, etc.), and thermal interface devices. The function of the thermal interface device is to fill the air gap between the heating element and the heat dissipation element, improve the thermal conductivity efficiency, and is usually used in communication equipment, computers and peripherals, power conversion equipment, storage modules, chip level packaging and other fields. The heat sink contacts the surface of the electronic component through the thermal interface device, and uses its thermal conductivity in the horizontal direction to quickly reduce the temperature at the location of the heating element during the operation of the electronic product, making the temperature of the electronic product more uniform, expanding the heat dissipation surface area to reduce the temperature of the entire electronic product, and improving the working stability and service life of the electronic product.

At present, widely used thermal conductive devices in the industry include thermal interface devices, graphite sheets, etc. Thermal interface devices mainly includeThermal conductive paste, sheet thermal conductive gap filling material, liquid thermal conductive gap filling material, phase change thermal conductive interface material and thermal conductive gelWait.

2.1.1 High thermal conductivity graphite film is the mainstream

The graphite material of high thermal conductivity graphite film has a unique grain orientation due to its carbon atomic structure, and has excellent planar thermal conductivity, which is much higher than the thermal conductivity of general pure copper. Its layered structure can adapt well to any surface, and has the advantages of low density (lightweight), high specific heat capacity (high temperature resistance), and long-term reliability, making it an excellent material for heat dissipation solutions. Therefore, in recent years, high thermal conductivity graphite film has been widely used in consumer electronics products such as smartphones, ultra-thin laptops, tablets, and LED TVs.

At present, thermal conductive graphite films are divided into two types: natural graphite films and artificial graphite films due to differences in raw materials and preparation methods. Due to the better thermal conductivity of artificial graphite film compared to natural graphite film, and the continuous reduction in cost and improvement in performance driven by technological progress, artificial graphite film has well met the heat dissipation needs brought about by the increasing heat generation and compact structure of consumer electronics and other products, and has a large development space.

As the 5G era approaches, electronic products have higher requirements for thermal management solutions. Therefore, more new requirements will be put forward for thermal conductive graphite film materials, focusing on the characteristics of thermal conductive devices, product forms, production processes, and expansion of application fields. There is a development trend that emphasizes both material production process upgrading and application field innovation.

From the perspective of product form, high thermal conductivity graphite films are mainly divided into various types such as single-layer high thermal conductivity films, composite high thermal conductivity films, and multi-layer high thermal conductivity films. Among them, single-layer high thermal conductivity films have the widest application range, while composite and multi-layer high thermal conductivity films are made by compounding with copper foil or multiple graphite films on the basis of single-layer high thermal conductivity films to meet more design functions and needs of customers. Among them, single-layer high thermal conductivity film mainly emphasizes its superior thermal conductivity coefficient; Multilayer high thermal conductivity films not only have high thermal conductivity, but also have certain thermal storage properties; Composite high thermal conductivity film has both thermal conductivity and thermal storage properties, as well as a certain shielding effect against radiation. The intelligent terminal products in the 5G era are accompanied by higher power consumption and heat dissipation requirements, as well as the trend of component innovation and upgrading. Therefore, composite and multi-layer thermal conductive graphite films are expected to have a wider range of applications.

From the perspective of production technology,Thermal conductive graphite filmIt is mainly processed on the basis of substrate treatment through high-temperature carbonization, graphitization and other processes, and the high-temperature firing process can be divided into sheet firing and roll firing technologies. Chip fired graphite is the process of cutting polyimide film (PI film) and placing it in a mold in a staggered manner, applying pressure, carbonizing, and graphitizing it. And roll burned graphite is an emerging technology in recent years, which involves winding PI film onto a roll, conducting carbonization heat treatment, and then graphitization heat treatment to form a roll shaped graphite film. Compared with the sheet burning process, the roll burning graphite technology has the advantage of saving manual stacking process, and is conducive to the continuous production of subsequent processes, which can significantly reduce costs. At the same time, a successful roll burning process can make the graphite film have good mechanical strength without the limitation of mold size, making it very suitable for the significantly growing heat dissipation needs in the 5G era, especially in large equipment such as base stations, with broad application prospects.

2.1.2 Coexistence of Multiple Innovative Thermal Conductivity Solutions

At present, most smartphones use graphite sheets as their heat dissipation solution, mainly due to the mature technology and relatively cheap price of graphite sheet heat dissipation. With the approaching of the 5G era and the continuous upgrading of functions, the performance and heat dissipation requirements of core components have significantly increased. Therefore, in addition to mainstream graphite sheets, various brand manufacturers are also constantly exploring other heat dissipation methods and adopting comprehensive solutions for various thermal conductivity products, constantly innovating and enriching thermal conductivity products.

At the Asian Consumer Electronics Show held in Shanghai in 2018, Dow Chemical's high-performance silicone business unit launched a new type of Taoxi TC-3105 silicone thermal conductive gel for thermal management of smart phone components, and replaced the original Dow Corning brand with the new brand Taoxi. The thermal conductive gel is mainly coated on the ceramic or plastic packaging surface of the main heating chip in the smart phone, and is used to replace the traditional finished heat dissipation pad. The cost is similar to that of the heat dissipation pad, but the thermal conductive gel can be cured at room temperature or under the chip's self heating. The contact surface formed after curing is far larger than the finished heat dissipation pad, thus greatly improving the heat dissipation effect. It can be seen that in the future, thermal conductive gel products are expected to maintain continuous innovation through material process upgrading.

At the same time, as the 5G era approaches, various smartphone manufacturers are increasing their innovation and application efforts in heat dissipation solutions in their recently released flagship models, preparing for subsequent large-scale introductions. Among them, heat pipe cooling technology, as the mainstream cooling solution in the PC field, has gradually been installed in smartphones. The heat pipe scheme is also commonly known as "water-cooled heat dissipation technology". Copper heat dissipation pipes are installed in mobile phones, and special thermal conductive liquids (water or ethylene glycol) are added to the pipes to absorb the heat emitted by the core components of the phone. The thermal conductive liquid gradually vaporizes and flows inside the pipes. When it flows to a low temperature, it releases heat energy and condenses into a liquid state, completing the rapid transfer of heat from the phone. The heat is dissipated through a fixed heat dissipation material connected to the heat pipe.

Currently, multiple mobile phone brands have adopted copper heat dissipation tube solutions, such as Samsung Galaxy Note 9, Meizu 16, Honor Note 10, etc. Huawei's attitude towards introducing heat dissipation tubes into mobile phones is also quite clear. The plan is to use 0.4mm copper heat dissipation plates in the 5G phones to be launched next year, further upgrading on the basis of copper tubes. The heat dissipation plate scheme is to weld two copper plates on all four sides, leaving a gap in the middle for air circulation. Due to the larger area, the heat dissipation effect is better. At present, the heat dissipation board scheme has been widely adopted in high-end lightweight laptops.

If the future heat dissipation board solution is widely applied in smartphones, suppliers are expected to mainly come from PC heat dissipation solution manufacturers, including Fujitsu from Japan, Shuanghong Technology from Taiwan (with a revenue of 1.5 billion yuan, PC business accounting for more than 40%, global market share of 13%), Chaozhong Technology, Qicheng Technology, Lizhi Technology, Hongzhun Precision, etc. Among them, Taiwanese manufacturers account for 70% of the global PC heat dissipation board share and are expected to benefit from the application of smartphone heat dissipation boards first. The supply of domestic smartphone cooling solutions is also based on the layout of heat pipes and heat plates, and is expected to gradually introduce innovative solutions with the customized needs of terminal manufacturers.

The heat dissipation of mobile phones mainly relies on the principles of heat convection and heat conduction, while copper tube water-cooled heat dissipation mainly depends on internal liquid heat convection. The effect of relying solely on heat pipes for heat dissipation still has certain shortcomings: 1) Heat pipes can accelerate heat transfer, but the degree of acceleration depends on the convective velocity, which is proportional to the cross-sectional area of the heat pipe. Most heat pipes in mobile phones are flat, and the convective effect is somewhat compromised; 2) Liquid has a high specific heat capacity, which can reduce the maximum temperature and slow down the temperature rise. However, in the case of limited heat pipe volume in mobile phones, the temperature control effect achieved by relying on a small amount of liquid is limited. At the same time, the production difficulty of heat dissipation plates is relatively high, and they require more space in mobile phones, so their price is much higher than the mainstream thermal graphite sheets in mobile phones, and their cost is several times higher than that of heat dissipation tubes. Combined with the high sales volume and trend of thinning and thinning of mobile phone products, there is still a certain bottleneck for the mass application of heat dissipation plates in mobile phones in the short term.

Therefore, whether it is a heat pipe or a heat sink, it only accelerates the transfer of heat from the phone's heating parts to the heat sink, and the final heat dissipation effect still depends on the heat convection between the heat sink and the air. The thermal characteristics of the heat sink material become the determining factor of the phone's heat dissipation effect. With the arrival of the 5G era in the future, the trend of lightweight and integrated internal components of smartphones is clear, and there are strict limitations on internal space. Therefore, the heat dissipation solutions suitable for smartphones will also develop towards ultra-thin and efficient directions, and will inevitably present a new situation of multiple heat dissipation products coexisting and constantly innovating material processes.

2.2 Electromagnetic shielding materials and devices: continuous upgrading of material technology

When electronic devices are working, they do not want to be interfered by external electromagnetic waves, nor do they want to emit electromagnetic waves that interfere with external devices and pose radiation hazards to the human body. Therefore, electromagnetic shielding is needed to block the propagation path of electromagnetic waves. The attenuation of electromagnetic shielding is mainly based on the principles of reflection and absorption of electromagnetic waves.

Electromagnetic shielding devices are used inelectromagnetic shielding materialOn the basis of secondary development, the required materials must have good conductivity. According to the preparation process of the materials, electromagnetic shielding materials mainly include three categories: 1) metal materials: directly select metal materials such as beryllium copper, stainless steel, etc; 2) Filler type: Adding a certain proportion of conductive filler to non-conductive substrate to make the material conductive. The substrate can be made of materials such as silicone, plastic, etc., and the conductive filler can be materials such as metal sheets, metal powders, metal fibers, or metallized fibers; 3) Surface coatings and conductive coatings: Electroplating of substrates, such as conductive fabrics. From the perspective of devices, the widely used electromagnetic shielding devices currently include conductive plastic devices, conductive silicone, metal shielding devices, conductive cloth pads, absorbing devices, etc.

The technological level of electromagnetic shielding devices is mainly dominated by the development of their materials, and the electrical conductivity, magnetic permeability, and material thickness of the materials are the three basic factors of shielding effectiveness. Electromagnetic shielding materials will develop towards higher shielding efficiency, wider shielding frequency, and better comprehensive performance, and various new materials will have more innovative applications in electromagnetic shielding. In the future technological development, electromagnetic shielding will develop towards good conductivity, simple processing technology, high cost-effectiveness, and suitability for large-scale production. In the future, more and more types of electronic devices will be included in the standards for electromagnetic compatibility management, and the standards for electromagnetic compatibility will become increasingly strict. It can be foreseen that the continuous upgrading trend of electromagnetic device process materials will be a deterministic direction.

Recently, a new shielding technology has emerged - conformal shielding. Unlike the traditional EMI shielding method for mobile phones that uses metal shielding covers, conformal shielding technology fully integrates the shielding layer and packaging. The module itself has shielding function, and after the chip is mounted on the PCB, there is no need to add an external shielding cover, which does not occupy additional equipment space. It is mainly used for SiP module packaging such as PA, WiFi/BT, Memory, etc., to isolate interference between the internal circuit of the package and the external system. Conformal shielding technology can solve the EMI interference between the internal and surrounding environment of SiP, with almost no impact on the packaging size and weight. It has excellent electromagnetic shielding performance and can replace large-sized metal shielding covers. In the future, it is expected to become popular with SiP technology and the demand for equipment miniaturization.

3. Domestic suppliers have promising development prospects

3.1 Domestic manufacturers layout the main links of the industrial chain

Electromagnetic shielding and thermal conductive materials and devices are in the middle of the industrial chain, with plastic pellets, silicone blocks, metal materials, fabrics, and other basic raw materials in the upstream, and end users such as communication equipment, computers, mobile phone terminals, automotive electronics, household appliances, and defense and military industries in the downstream. Among them, electromagnetic shielding and thermal conductivity devices are processed twice based on electromagnetic shielding and thermal conductivity materials.

In the midstream stage, some companies mainly develop, design, and produce electromagnetic shielding and thermal conductive material products, which are then delivered to device processing manufacturers. Another group of companies independently design and produce materials and perform secondary processing of devices after purchasing raw materials from external sources, and finally deliver the electromagnetic shielding and thermal conductive devices after die-cutting to downstream manufacturers. Relatively speaking, the material production process has higher technical barriers and fewer participants, so the gross profit margin level is generally higher than that of the device processing process.